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General Guidelines for Historic Districts and Individual Landmarks - 09.01.2021CITY OF BOULDER LANDMARKS BOARD GENERAL DESIGN GUIDELINES FOR BOULDER'S HISTORIC DISTRICTS AND INDIVIDUAL LANDMARKS NOVEMBER 2007 UPDATED SEPTEMBER 2021 1 CITY OF BOULDER LANDMARKS BOARD ACKNOWLEDGEMENTS Landmarks Preservation Advisory Board (1998 - 2007) Kathy Arnold Leslie Durgin Lisa Egger Michael Holleran Nancy Kornblum Leonard May Tim Plass Lisa Podmajersky Sharon Rosall Leland Rucker Rory Salance Kent Stutsman Kirk Watson Consultant Nancy Lyons, Preservation Partnership City of Boulder Staff A number of current and former city employees contributed to this project, including Ruth McHeyser, Deon Wolfenbarger, Neil Holthouser, Lara Ramsey, Bohdy Hedgcock, Marcy Cameron, Chris Meschuk and James Hewat. Photos and Graphics Bohdy Hedgcock, Robin Madel & Matt Russell - City of Boulder Winter & Company Carnegie Branch Library for Local History Denver Public Library – Western History Collection Funding This project was sponsored by the City of Boulder Landmarks Advisory Board and has been financed in part with Federal funds from the National Historic Preservation Act, administered by the National Park Service, U.S. Department of the Interior and for the Colorado Historical Society. However, the contents and opinions do not necessarily reflect the views or policies of the U.S. Department of the Interior or the Society, nor does the mention of trade names or commercial products constitute an endorsement or recommendation by the Department of the Interior or the Society. This program receives Federal funds from the National Park Service. Regulations of the U.S. Department of the Interior strictly prohibit unlawful discrimination in departmental Federally assisted programs on the basis of race, color, national origin, age or handicap. Any person who believes he or she has been discriminated against in any program, activity, or facility operated by a recipient of Federal assistance should write to: Director, Equal Opportunity Program, U.S. Department of the Interior, 1849 C Street, N.W., Washington, D.C. 20240. 2 CONTENTS 1. INTRODUCTION 5 1.1 Historic Preservation Program 6 1.2 Purpose of the Design Guidelines 8 1.3 A History of Boulder 11 1.4 Architectural Styles In Boulder 14 1.5 Review Process 19 2. SITE DESIGN 23 2.1 Building Alignment, Orientation, and Spacing 24 2.2 Streetscape and Landscaping 25 2.3 Alleys 26 2.4 Parking, Driveways 27 2.5 Sidewalks 28 2.6 Fences 29 2.7 Pools 31 3. ALTERATIONS 34 3.1 Roofs, Skylights, and Solar Panels 35 3.2 Roof Decks and Balconies 36 3.3 Decks 37 3.4 Porches 38 3.5 Dormers 39 3.6 Exterior Materials: Walls, Siding, and Masonry 40 3.7 Windows, Storm Windows, and Shutters 41 3.8 Doors and Storm Doors 47 4. ADDITIONS TO HISTORIC STRUCTURES 50 4.1 Protection of Historic Structures and Sites 53 4.2 Distinction from Historic Structures 53 4.3 Compatibility with Historic Structures 54 4.4 Compatibility with Historic Site and Setting 54 4.5 Key Building Elements 55 3 5.ADDITIONS TO NON-HISTORIC STRUCTURES 57 6.NEW PRIMARY STRUCTURES 59 6.1 Distinction from Historic Structures 60 6.2 Site and Setting 60 6.3 Mass and Scale 61 6.4 Materials 62 6.5 Key Building Elements 62 7.GARAGES & OTHER ACCESSORY STRUCTURES 64 7.1 Existing Historic Accessory Structures 64 7.2 New Accessory Structures 64 8.MISCELLANEOUS 67 8.1 Paint and Paint Colors 68 8.2 Energy Efficiency 69 8.3 Mechanical and Utility Facilities 70 8.4 Signs 70 8.5 Lighting 72 8.6 Artwork 72 8.7 Public Improvements 73 8.8 Americans with Disabilities Act 73 9.DEFINITIONS 74 4 CITY OF BOULDER LANDMARKS BOARD INTRODUCTION 5 GENERAL DESIGN GUIDELINES 1. INTRODUCTION 1.1 Historic Preservation in Boulder The early 1970’s saw an increase in the demolition of existing buildings with no thought as to their historical or architectural value to Boulder’s history. Among those demolished was Central School, the first school to have a graduating class in the Colorado Territory. Today, at the corner of Walnut and 15th is a plaque, embedded in rock, commemorating the school. Out of the school's destruction rose the demand for a legal mechanism for evaluating historic sites. In 1974, the Boulder Landmarks Ordinance was passed. The ordinance sets out the procedures for designation, design review, and the appointment and powers of the Landmarks Preservation Advisory Board (LPAB). The purpose of the historic preservation program as stated in the Ordinance is as follows: (a) The purpose of this chapter is to promote the public health, safety, and welfare by protecting, enhancing, and perpetuating buildings, sites, and areas of the city reminiscent of past eras, events, and persons important in local, state, or national history or providing significant examples of architectural styles of the past. It is also the purpose of this chapter to develop and maintain appropriate settings and environments for such buildings, sites, and areas to enhance property values, stabilize neighborhoods, promote tourist trade and interest, and foster knowledge of the city's living heritage. (b) The city council does not intend by this chapter to preserve every old building in the city but instead to draw a reasonable balance between private property rights and the public interest in preserving the city's cultural, historic, and architectural heritage by ensuring that demolition of buildings and structures important to that heritage will be carefully weighed with other alternatives and that alterations to such buildings and structures and new construction will respect the character of each such setting, not by imitating surrounding structures, but by being compatible with them. Landmarks Preservation Advisory Board Mission: To protect, enhance, and perpetuate buildings, sites, and areas of the city reminiscent of past eras, events, and persons important in local, state or national history or provide significant examples of architectural styles of the past. .… also ... to develop and maintain appropriate settings and environments for such buildings, sites, and areas to enhance property values, stabilize neighborhoods, promote tourist trade and interest, and foster knowledge of the city’s living heritage. More than 200 properties have been designated as local landmarks, along with these historic districts: Floral Park 1977 Chauta uqua 1978 Mapleton 1982 West Pearl 1994 Chamberlain 1995 Downtown 1999 Grandview 2000 Hillside 2001 Highland Lawn 2005 University Place 2006 16th Street 2006 A complete listing of individual landmarks is available on the city's website: boulderhistoricpreservation.net 6 INTRODUCTION CITY OF BOULDER LOCAL HISTORIC DISTRICTS (2007) 7 GENERAL DESIGN GUIDELINES 1.2 Purpose of the Design Guidelines The intent of the design review process is to ensure that proposed alterations of Landmark properties will not adversely affect or destroy their historic character or architectural integrity and that all changes are consistent with the spirit and purpose of the Landmark Preservation Ordinance. The Landmarks Board adopted the Secretary of the Interior’s Standards for Rehabilitation as the basis for guidance on rehabilitation design for historic properties. These guidelines expand those Standards and bring focus to Boulder’s own historic context and resources. The guidelines are intended to be used as an aid to appropriate design and not as a checklist of items for compliance. The purpose of the design guidelines is to facilitate both the application and approval of alterations proposed for design review by 1) providing the owners of historic properties some assistance in making decisions about maintenance and improvements, and 2) providing the Landmarks Board with a framework for evaluation of proposed improvements. The guidelines reflect the Landmarks Board’s philosophy that underlies all its decisions: to encourage the preservation and careful treatment of the city’s historically significant resources, while recognizing the need for continuing adaptation and improvements to these resources. The General Design Guidelines serve as the guiding document for present and future residential historic districts and individual landmarks, supplemented by district-specific guidelines where those have been adopted. The district-specific guidelines are available from the Planning Department. Call a Preservation Planner at (303) 441-1880 for more information. For individually landmarked commercial buildings and for the Downtown Historic District, refer to the Downtown Design Guidelines. Before you begin to formulate plans for any changes to your building, find out whether it is considered individually significant, contributing, contributing-restorable, or non-contributing. This information will help you to better understand these guidelines as they apply to your building. You can find this information on  Adopted by the Landmarks Board as administrative regulations, 11/7/1990 Survey sheets like these document Boulder's historic resources. 8 INTRODUCTION historic surveys completed for all buildings in historic districts and for landmark structures. Surveys are available from the Planning Department at 1739 Broadway and at the Carnegie Branch Library for Local History, 1125 Pine Street, Boulder. It should be noted that the status of buildings can change over time, and not all surveys are up to date. The determination of contributing or non- contributing status is ultimately made by the Landmarks Board in consultation with staff. The Secretary of the Interior’s Standards for Rehabilitation 1. A property shall be used for its historic purpose or be placed in a new use that requires minimal change to the defining characteristics of the building and its site and environment. 2. The historic character of a property shall be retained and preserved. The removal of historic materials or alteration of features and spaces that characterize a property shall be avoided. 3. Each property shall be recognized as a physical record of its time, place, and use. Changes that create a false sense of historical development, such as adding conjectural features or architectural elements from other buildings, shall not be undertaken. 4. Most properties change over time; those changes that have acquired historic significance in their own right shall be retained and preserved. 5. Distinctive features, finishes, and construction techniques or examples of craftsmanship that characterize a property shall be preserved. 6. Deteriorated historic features shall be repaired rather than replaced. Where the severity of deterioration requires replacement of a distinctive feature, the new feature shall match the old in design, color, texture, and other visual qualities and, where possible, materials. Replacement of missing features shall be substantiated by documentary, physical, or pictorial evidence. 7. Chemical or physical treatments, such as sandblasting, that cause damage to historic materials shall not be used. The surface cleaning of structures, if appropriate, shall be undertaken using the gentlest means possible. 8. Significant archeological resources affected by a project shall be protected and preserved. If such resources must be disturbed, mitigation measures shall be undertaken. 9. New additions, exterior alterations, or related new construction shall not destroy historic materials that characterize the property. The new work shall be differentiated from the old and shall be compatible with the massing, size, scale, and architectural features to protect the historic integrity of the property and its environment. 10. New additions and adjacent or related new construction shall be undertaken in such a manner that if removed in the future, the essential form and integrity of the historic property and its environment would be unimpaired. A searchable database of survey sheets of individual landmarks and buildings within Boulder’s local historic districts is available from the Carnegie Library for Local History, Boulder and online at: localhistory.boulderlibrary.org 9 GENERAL DESIGN GUIDELINES The definitions below help to explain the different categories of significance:  Local Landmark Buildings: Those buildings that are officially designated as city of Boulder local landmarks. These buildings have a special character and historical, architectural, or aesthetic interest or value in Boulder's local history.  Individually Significant Buildings: Those buildings that are considered individually eligible for the National Register of Historic Places or for local landmark designation.  Contributing Buildings: Those buildings built during the district's period of significance that exist in comparatively original condition, or that have been appropriately restored, and clearly contribute to the historic significance of the district. Such buildings may have compatible additions.  Contributing-Restorable Buildings: Those buildings built during the district's period of significance that have original material that has been covered, or buildings that have experienced some alteration, but that still convey some sense of history. These buildings would more strongly contribute, however, if they were restored. Such buildings may have less compatible additions.  Non-Contributing Buildings: Those buildings built during the district's period of significance that have been altered to such an extent that historic information is not interpretable and restoration is not possible. This includes buildings erected outside the period of significance that are not individually significant.  Significant Newer Buildings: Those buildings that have not yet achieved historic significance but have achieved architectural significance as excellent examples of their period. 10 INTRODUCTION 1.3 A History of Boulder The Boulder valley was first the home of American Indians, primarily the Southern Arapaho tribe that maintained a village near Haystack Mountain. Utes, Cheyennes, Comanches, and Sioux were occasional visitors to the area. Gold seekers established the first non-native settlement in Boulder County on October 17,1858 at Red Rocks near the entrance to Boulder Canyon. Less than a year later, on February 10, 1859, the Boulder City Town Company was organized by A.A. Brookfield, forty-four lots were laid out at a purchase price of $1,000 each; a price that was later lowered in order to attract more residents Part of the Nebraska Territory until February 29, 1861, when the U.S. Congress created the Territory of Colorado, Boulder City grew slowly. It developed as a supply base for miners going into the mountains in search of gold and silver. Boulder City residents provided miners with equipment, agricultural products, housing and transport services, and gambling and drinking establishments. Competition among Boulder County settlements for new residents and businesses was intense. As a mining supply town, Boulder residents were more settled than in the mining camps. Economic stability was a necessity and residents encouraged the establishment of railroad service, hospital and school buildings, and a stable town government. Boulder's first schoolhouse was built in 1860 at the southwest comer of Walnut and 15th Street, the first in the territory. Also in 1860 a group of Boulder residents began lobbying to have the University located in Boulder. By 1874 Boulder had won the designation, secured a donated 44.9-acre site and raised $15,000 to match a similar grant by the state legislature. Construction of Old Main signaled the opening of the University with classrooms, offices, an auditorium and the President's living quarters all located there. Transportation was improved in 1873 with railroad service coming to Boulder. Gradually tracks were built to provide service to Golden and Denver and to the mining camps to the west. In 1890, the railroad depot was constructed on Water Street (now Canyon Boulevard) and 14th Street. Bird's Eye View of Boulder City, 1876 Carnegie Branch Library for Local History, Boulder Historical Society Collection 11 GENERAL DESIGN GUIDELINES City government was formalized in November 1871, when the town of Boulder was incorporated. Designation of Boulder as the county seat occurred in 1867 and led to the construction of the first courthouse at its present site in 1883. It burned to the ground in 1932 and was replaced by the current courthouse in 1934. Amenities and health services were developed, even in periods of little growth. The first Post Office was established in 1860; a hospital was built in 1873; 1874 saw the arrival of the telegraph, a water system and the first bank. The initial residential area was located in what is now downtown and in some parts of the Goss/Grove, Whittier and Mapleton Hill neighborhoods. As commercial expansion took over downtown housing, the surrounding neighborhoods remained primarily residential areas. At the turn of the century growth of the University led to the development of University Hill. One mark of elegance for residents was the flagstone sidewalks, first installed during the 1880's. The first private school in Boulder, Mt. St. Gertrude Academy, was opened in 1892. Boulder, by then accessible to visitors by railroad, was known as a community with a prosperous economy, a comprehensive educational system, and well- maintained residential neighborhoods. It was no wonder that the railroad recommended Boulder as a site for a Chautauqua in 1897. Boulder residents passed a bond issue to buy the land, and the now familiar Chautauqua Park is listed both on the National Register and as a locally designated landmark. By 1905 the economy was faltering and Boulder counted heavily on tourism to boost its fortunes; however, Boulder had no first class hotel to attract summer visitors and group meetings. By 1906, a subscription drive had raised money to begin construction. The first event at the new Hotel Boulderado was a reception for Boulderites on December 30, 1908. The hotel opened to the public for business on January 1, 1909. Tourism continued to dominate the Boulder economy for the next forty years. Each summer shopkeepers, transport firms, and lodging managers eagerly awaited the influx of Chautauqua residents (primarily from Texas) and other visitors. By World View of the Flatirons and Boulder, 1920 Denver Public Library – Western History Collection 12 INTRODUCTION War II, when tourism declined, the University had unknowingly provided another opportunity for growth. With the location of the U.S. Navy's Japanese language school at CU young men and women from around the country became acquainted with the city and liked it. Following World War II many of these trainees returned as students, professionals and business people, joining veterans attending the University on the G.I. Bill. Boulder's population had not increased significantly since the 1920’s. The 1920 census showed 11,006 residents while the 1940 count was 12,958. After the first influx of new residents in the late 1940's, the count soared to 20,000 in 1950. New residents meant both new opportunities and new challenges. Although jobs were needed, townspeople wanted to preserve the beautiful natural setting and amenities developed over the years. By 1950, Boulder leaders were actively recruiting new "clean" industry and improved transportation; securing a new highway, the Boulder-Denver Turnpike; and the National Bureau of Standards in 1952. Other research and development industries soon followed. The housing shortage and need for additional business and public buildings attracted young and talented architects. New subdivisions were planned including the Highland Park-Martin Acres neighborhood located on the historic Martin Farm and the North Boulder developments from Balsam north, originally part of the Tyler Farm. New neighborhoods brought the city's first two shopping centers, North Broadway and Basemar. With the completed turnpike to downtown Denver, Boulder continued to expand. From 1950 to 1972 the population grew from 20,000 to 72,000. With the purchase of thousands of acres of open space beginning in 1967, the adoption of the Boulder Valley Comprehensive Plan in 1970, passage of the building height restriction ordinance in 1972, and the residential growth management ordinance in 1977, Boulder began a period of infill and re-use of its past architectural development that continues to the present. The Historic Preservation Code was passed in September 1974. The ordinance is instrumental in preserving significant portions of our past while encouraging rehabilitation of historic buildings. Boulder-Denver Turnpike, 1952 Carnegie Branch Library for Local History, Boulder Historical Society Collection 13 GENERAL DESIGN GUIDELINES 1.4 Architectural Styles in Boulder Understanding the stylistic trends, the design intent, and the traditional use of building materials is important to the evaluation of a structure’s historic integrity and consequently to rehabilitation design. While a large portion of Boulder's historic residential properties are properly identified as “vernacular”, they also include examples of a broad range of architectural styles that reflect the evolution of Colorado architecture dating from the 1880’s. The following styles are found in Boulder. The descriptions are excerpted from a 1983 publication of the Colorado Historical Society, A Guide to Colorado Architecture. Vernacular Wood Frame (late 1860-present) By far the most common style of architecture, Vernacular Wood Frame structures have been built throughout Colorado since 1860. The Vernacular is an indigenous style generally constructed with locally available materials according to traditional building practice. They are simple in form and detail and generally void of ornamentation. These simple, modest homes are divided into four types according to floor plan and roof shape: the Gabled “L”, the Front Gable, the Hipped Gable, and the Side Gable. These buildings are wood frame construction and are usually sided with clapboard or wood shingles or a combination of the two. Vernacular Masonry (late 1860-present) Vernacular Masonry is another very common form of architecture found all over Colorado and dates from the late 1860’s. Although not as common as Vernacular Wood structures, these unpretentious building are numerous enough to warrant a separate category. They are generally composed of brick, stone, or concrete block and are similar in massing to their wood counterparts. As with Vernacular Wood structures, these buildings are simple in detail and are designated according to roof shape and floor plan into four categories: the Gabled “L”, the Front Gable, the Hipped Box, and the Side Gable. Italianate (1870-1910) Like many Victorian styles, the Italianate emphasized vertical proportions and richly decorative detailing. It was found on residential, commercial, and institutional structures throughout Colorado from about 1870 up until the turn of the century and is either wood or masonry construction. The Italianate style is characterized by a low pitched, hip roof, wide overhangs, bracketed cornice, a variety of fenestration (usually very tall, Italianate Austin House Pine Street Vernacular Wood Frame Greenman House Mapleton Avenue Vernacular Masonry John Day House 19th Street 14 INTRODUCTION thin, double-hung, one-over-one winnows), molded window surrounds, and occasionally a cupola or balustraded balcony. Simple Italianate structures have a hipped roof, bracketed eaves, and molded surrounds. A more elaborate or High Style example may feature arcaded porches, corner quoins, towers, and ornate detailing. Second Empire (1870-1910) The Second Empire style is most easily identified by the use of a Mansard roof form, a double-pitched roof with a steep lower slope. The roof is usually pierced with dormer windows allowing light to this second or third floor. Decorative elements on the facades include triangular pediments over windows and porches and pilasters and columns at building corners. Queen Anne (1880-1910) Queen Anne is perhaps the most ornate style of the Victorian Period evident in Colorado, and was popular between 1880 and 1910. The style varies from highly decorative commercial examples to more restrained version found in many residential neighborhoods. General characteristics include a vertical orientation, asymmetrical massing, corner towers and bays, prominent decorative porches, projecting gables, and contrasting materials. First stories are often brick or stone with wood frame upper stories finished with wood shingles or clapboards. Roof forms are often complex with gabled or hip dormers and tower elements. Wide front or wrap-around porches are typically found on front and side elevations with elaborate trim and turned posts. The degree of ornamentation usually distinguishes the High Style from the vernacular. Ornamentation is emphasized on a High Style Queen Anne through the use of scalloped and painted shingles in the gable ends, and decorative bargeboards, sunburst detailing, and turned spindles on porches and balconies. The corner tower is prominent, but not universally present. The Vernacular Queen Anne is generally less ornate, but usually features the shingled gables, asymmetrical massing and some decorative detailing. The vernacular examples have enough decoration to distinguish them from the categories that are strictly vernacular. Queen Anne McAllister House Pine Street Second Empire Chauncey Stokes House Pine Street Queen Anne Temple-Bowron House Pine Street 15 GENERAL DESIGN GUIDELINES Edwardian Vernacular (1900-1920) Edwardian Vernacular structures are basically Post-Victorian residences similar to the Queen Anne style in form and massing, but lacking ornamentation. Sometimes called “Princess Anne,” these buildings feature multi-gabled roofs, asymmetrical massing, simple surfaces, and occasionally wrap- around porches, short towers, and some classical details. Terrace (1880-1920) The Terrace is considered to be somewhat unique in Colorado and dates from the late 1880’s through 1920. These structures are basically one or two-story brick building with a flat roof and corbelled cornice. The style is evident in a few single-family homes, but most common as duplexes or larger multi-family homes. Many have individual porches at each entrance. While the most common cornice treatment is brick corbelling, occasionally a separate cornice with brackets or parapets at the roofline are evident. Stylistic elements such as Richardsonian arches or Italianate bracketed cornices are used occasionally, but the basic flat-roofed. Rectangular form predominates. Foursquare (1900-1930) One of the most commonly found styles in Colorado after 1900, the Foursquare is easily recognized by its square plan and overall simplicity. The majority of these homes were built during the first three decades of the 20th century. The typical Foursquare is a two-story, hipped roof structure with central front dormer, minimal decoration, broad overhanging eaves with brackets or modillions, classical frieze with dentils, and a porch with hipped roof supported bu simple, Doric columns or square posts. Occasionally, a Foursquare will feature a shaped gable or will be considerably larger with more elaborate ornamentation, but, in each case, the basic square plan is predominant. Classic Cottage (1910-1930) The Classic Cottage is basically a one-story version of the Foursquare. It features an elongated hipped roof with central front dormer, a front porch with thick porch posts or round, simplified Doric columns supporting the porch roof. Popular between 1910 and 1930, the style was most commonly used in residential architecture, although occasionally it was used for schoolhouses, train depots, or small institutional buildings. Building materials were almost always masonry, particularly brick, with a few rare frame examples. Ornamentation is generally limited to window surrounds and flared eaves on the dormer. Edwardian Vernacular Lamb House Spruce Street Foursquare Mayall-Pickett House Highland Avenue Terrace Johnson-Betasso Terrace Pearl Street Classic Cottage Mapleton Avenue 16 INTRODUCTION Colonial Revival (1900-1930) Classical or Colonial Revival buildings constructed in the early twentieth century generally have classical detailing. Buildings in this style vary widely in size, may be of wood or masonry construction, and have details such as pediments, dentiled cornices and multi-paned windows. Front doors are usually accented with pediments or fanlights and porches are typically small with slender columns. Roof forms can be hipped or gabled, but are usually simple in massing. Mission (1900-1930) The Mission style is most easily identified by the curvilinear shaped gable and simplicity of form. Also, characteristic is a stucco or plaster finish, arcades, tile roof, and, occasionally, arched windows. There is usually a small round window or round ornament located in the center of the shaped gable. Towers and iron balconies are evident on larger buildings. Tudor Revival (1910-1930) The most dominant features of the Tudor Revival style are the half-timbering that covers the upper story, and the very steeply pitched roof. The exterior is textured, using brick, stone, or stucco, and, together with the timbering, give the house a picturesque composition. Constructed in Colorado during the 1910s and 1920s, these homes also featured gabled or hipped roofs covered with tile, slate, or shake shingles, and decorated chimney detailing. Windows are generally mullioned casements, with an occasional bay window. Mediterranean (1920-1930) The key to distinguishing the Mediterranean style is the tile roof and restrained ornamentation (as opposed to the elaborate details on a Spanish Colonial Revival structure). Built in Colorado during the 1920’s, these structures are generally stucco or brick, often painted white to contrast the brightly colored roof tiles. Roofs are low-pitched gable or flat with a parapet on smaller homes; they are low pitched hipped on some larger homes. Another characteristic feature is the extension of a side or front wall to form an arcaded entrance or porch. Windows are sometimes casements, framed by wooden or wrought iron grills or small second story balconies. The Mediterranean style was used for churches, schools, and residences, both on a grand scale and on more modest homes. The heavy tile roof is generally the dominant characteristic. Tudor Revival Ekeley House 11th Street Mediterranean David H. Holmes House 11th Street Colonial Revival Henrietta Somers House Baseline Road Mission Wahlstrom Mission/Terrace 19th Street 17 GENERAL DESIGN GUIDELINES Bungalow (1920-1940) The Bungalow style incorporates a wide range of styles from Craftsman to Prairie and Mission style buildings. Often categorized as modest one or one and one half-story buildings, defining features include large, covered porches, low overhanging roof forms and large scale building elements. Porch columns tend to be squared and tapered and often sit on pedestals. Bungalows can be wood or masonry, but share these common elements. Modern (1920 - present) Architecture associated with the Modern movement is identified by an emphasis on design that was clearly of the Machine Age, with standardization of parts, absence of non- functional decoration, and structural "honesty" as hallmarks. Flat roofs and smooth wall surfaces were favored. Both the Modernistic style (1920 - 40) and the International style (1925 - present) are products of this more austere modernism. Bungalow 6th Street Modern Thornton House 13th Street 18 INTRODUCTION 1.5 Review Process What is Subject to Review? The Boulder Revised Code’s Historic Preservation Ordinance (9-11-18, B.R.C., 1981) outlines the process and criteria for reviewing changes to individual landmarks and buildings in historic districts. Any alteration to the exterior of a building or site in a locally designated historic district or on a Landmark site requires a Landmark Alteration Certificate. Items such as changing the paint color, major landscaping projects and the addition of storm windows do not require a building permit, but they do require a Landmark Alteration Certificate. What is the Process for Review? There are three levels of review.  Staff Level Review: The following alterations can usually be reviewed within a few days by calling a city Preservation Planner at 441-1880: re-roofing, paint, landscaping, and rear or side yard fences lower than 5 feet in height with a minimum of 1" spacing between the pickets. For projects in downtown, staff may also review signs, awnings and railings. If such a proposal clearly meets the criteria outlined by the preservation code (see sidebar), a Preservation Planner will issue a Landmark Alteration Certificate, and you can commence your project. (You will also need a fence permit for fences and a building permit for re-roofing prior to beginning any work, however).  Landmarks Design Review Committee: All other projects will be reviewed by the Landmarks Design Review Committee, which meets weekly and consists of two members of the Landmarks Board and one member of the city Planning Department (a city Preservation Planner). Call a Preservation Planner to schedule your review with the Committee. The meetings are relatively informal, and you are encouraged to bring your proposal early in the design process for a conceptual review. As the project becomes finalized, the Committee determines whether it meets the guidelines set forth in this document and in the Boulder Historic Preservation Code. If it does, the Committee will issue an Alteration Certificate, and you can commence with your project after getting the necessary permits. If the vote of the Committee is divided, the application goes forward for review by the five-member Landmarks Board at a public hearing unless you choose to withdraw the application for revision and resubmittal. Section 9-11-18 of the Boulder Revised Code establishes criteria for the approval of Landmark Alteration Certificates: 1. The proposed work preserves, enhances, or restores and does not damage or destroy the exterior architectural features of the landmark or the subject property within an historic district; 2. The proposed work does not adversely affect the special character or special historical, architectural, or aesthetic interest or value of the landmark and its site or the district; 3. The architectural style, arrangement, texture, color, arrangement of color, and materials used on existing and proposed structures are compatible with the character of the existing landmark and its site or the historic district; and 4. With respect to a proposal to demolish a building in an historic district, the proposed new construction to replace the building meets requirements 2 and 3 above. The complete historic preservation ordinance is available online at: bouldercolorado.gov 19 GENERAL DESIGN GUIDELINES  Landmarks Board Public Hearing: In addition to projects referred to the Board by the Design Review Committee, the full Landmarks Board reviews all demolition and new construction applications. Sheds under 60 square feet in size and one-story single car garages under 340 square feet are exceptions, and can be reviewed by the Design Review Committee. Landmarks Board public hearings are held monthly, and agendas are published in the newspaper 10 days in advance. Decisions are based on the majority vote of the five-member Board and standards in the Code. Call Up by City Council The decision of the Landmarks Board is subject to call up by the City Council. If a majority of Council votes to call up the Board’s decision, it is re-considered at a subsequent City Council public hearing. If council does not call it up, the Board’s decision is final. Other Permit Requirements and Compliance with City Codes Please note that obtaining a Landmark Alteration Certificate does not include review of your project for all city requirements. In addition to meeting the guidelines, design and building plans must meet all requirements of the City of Boulder Revised Code, including, without limitation, the Land Use and Structure Regulations of Titles 9 and 10, B.R.C. 1981. The land use regulations include limitations on building setbacks from property lines, maximum building heights, and minimum solar access requirements. Building, fire, mechanical and plumbing requirements are covered in the Structure section of these regulations. The sign code includes limitations on the size and placement of signs. For direct questions regarding the building requirements or Land Use regulations, call the Planning and Development Services Center at 441-1880. Submittal Requirements The information you submit with your application is the only description the Landmarks Design Review Committee will have of your design. It therefore should illustrate, as precisely as possible, what you have in mind. For further information or to schedule a review by the Landmarks Design Review Committee, please contact the Planning Department, 1739 Broadway, Suite 300, (303) 441-1880. Incentives for Landmarking As a way to encourage landmark designation of the city's eligible historic resources, the city and state offer a variety of incentives to property owners including:  State income tax credit for 20% of approved rehabilitation costs (up to $50,000 per property) for local landmarks and contributing buildings within historic districts  Federal Investment Tax Credit for National Register properties used for commercial purposes  Eligibility for Colorado Historical Fund grants  The waiver of sales tax on construction materials at the time of building permit application  The potential for exemptions or variances to a variety of building code and zoning requirements. For complete information on these benefits contact a Preservation Planner by calling (303) 441-1880. 20 INTRODUCTION The following are required for review: 1. Application. 2. Photographs. Show all the views of the existing building and at least a portion of the neighboring buildings. 3. Scaled Site Plan. A site plan shows a view of your property from above. Show the property boundaries, existing buildings, significant trees and landscape features, and your proposed changes. Include a north arrow and the location of adjacent buildings, streets and alleys. 4. Elevations. An elevation is a scaled drawing of the front, rear or side of a building. Illustrate elevations of all relevant views of the alteration at the same scale to which the floor plans are drawn. Accurately label them, and include the existing building with as much detail as necessary to show how the old and the new relate to each other. 5. Floor Plans. Include floor plans drawn at a scale of not less than 1/8" = 1'0". Include a north arrow and show the existing building and how your alteration relates to it. It should be complete enough to show any exterior stairs, porches, decks, etc., and should include a roof plan. 6. Materials. List the visible exterior materials and describe them as fully as possible. Samples of these materials are always helpful. 7. Color. If your plans include paint or stain, describe the color and include a sample of the colors. A good way to show the color scheme is to color one or more of the elevations. 8. Models. For new buildings or for proposals that alter the scale and/or mass of the original building, a scaled model may be required. Note that models need not be expensive: a simple massing model can be made by tracing each elevation onto cardboard, gluing all sides together, and adding roofs and appurtenances such as dormers. 21 GENERAL DESIGN GUIDELINES PRESERVATION APPROACHES & TECHNIQUES While every historic project is different, the Secretary of the Interior has outlined four basic approaches to responsible preservation practices. Determining which approach is most appropriate for any project requires considering a number of factors, including the building’s historical significance and its existing physical condition.  Preservation places a high premium on the retention of all historic fabric through conservation, maintenance and repair.  Rehabilitation emphasizes the retention and repair of historic materials, but more latitude is provided for replacement because it is assumed the property is more deteriorated prior to work.  Restoration focuses on the retention of materials from the most significant time in a property's history, while permitting the removal of materials from other periods.  Reconstruction establishes limited opportunities to re-create a non- surviving site, landscape, building, structure, or object in all new materials. The Secretary of the Interior’s website outlines these approaches and suggests recommended techniques for a variety of common building materials and elements. An example of appropriate and inappropriate techniques for roofs is provided in the sidebars. Additional information is available from preservation staff and the Secretary’s website at: www.nps.gov/tps/standards.htm APPROPRIATE techniques for roofs Identifying, retaining, and preserving roofs that are important in defining the overall historic character of the building. Protecting and maintaining a roof by cleaning the gutters and downspouts and replacing deteriorated flashing. Stabilizing deteriorated or damaged roofs as a preliminary measure, when necessary, prior to undertaking appropriate preservation work. Repairing a roof by reinforcing the historic materials. Repairs may generally include the limited replacement in kind- -or with compatible substitute material--of extensively deteriorated or missing features. Replacing in kind a roof feature, such as a dormer or cupola that is too deteriorated to repair - if the overall form and detailing are still evident - using the physical evidence as a model to reproduce the feature. Recreating the documented design of exterior features such as the roof shape and coverings. INAPPROPRIATE techniques for roofs Altering the roof and roofing materials which are important in defining the overall historic character of the building so that, as a result, the character is diminished. Failing to stabilize a deteriorated or damaged roof until additional work is undertaken, thus allowing further damage to occur to the historic building. Replacing historic roofing material instead of repairing or replacing only the deteriorated material. Failing to reuse intact slate or tile when only the roofing substrate needs replacement. Replacing an entire roof feature such as a cupola or dormer when limited replacement of deteriorated and missing parts is appropriate. Applying paint or other coatings to roofing material which has been historically uncoated. Introducing a new roof feature that is incompatible in size, scale, material and color. 22 CITY OF BOULDER LANDMARKS BOARD SITE DESIGN 23 GENERAL DESIGN GUIDELINES 2. SITE DESIGN Site design includes a variety of character-defining elements of our historic districts and buildings. Individual structures are located within a framework of streets and public spaces that set the context for the neighborhood. How structures occupy their site, in terms of alignment, orientation, and spacing, creates much of the context of the neighborhood. In combination with public and private walks, fences, tree lawns, landscaping, and retaining walls, the site design features help to define individual sites and the relationship between public and private space in a neighborhood. 2.1 Building Alignment, Orientation, and Spacing The pattern of setbacks is an important element in defining neighborhood character. A front yard setback serves as a transitional space between the public sidewalk and the private building entry. When repeated along the street, these yards enhance the character of the area. The relatively uniform alignment of building fronts, as well as similar spacing between primary buildings, contributes to a sense of visual continuity. Traditionally, the primary entrance of a building faced the street and, depending on the architectural style of the house, was often sheltered by a one-story porch. This feature provided an additional transition from the public to the private space and helped establish a sense of scale to the neighborhood. The primary structure generally "stepped down" to one story at the rear of the lot. This, and smaller accessory structures along the alley, helped frame the rear yard. GUIDELINES .1 Locate structures within the range of alignments seen traditionally in the area, maintaining traditional setbacks at the front, side and rear of the property. .2 Building proportions should respect traditional patterns in the district. For example, many areas are characterized by relatively narrow lots and vertically proportioned front facades, taller than they are wide. In such an area, it would be inappropriate to introduce horizontally proportioned front facades. 2.1.1 / 2.1.7 The marked building is built outside the range of typical setbacks and occupies a much larger percentage of the back yard area than typical. x 2.1.2 In areas characterized by vertically proportioned facades, buildings with a horizontal emphasis are inappropriate. x 24 SITE DESIGN 25 .3 Orient the primary building entrance to the street. .4 Preserve the original location of the main entry and walk. .5 A new porch may encroach into the existing alignment only if it is designed according to the guidelines and if it is appropriate to the architectural style of the house. .6 In neighborhoods with alleys, garages should be located at the rear of the lot and accessed from the alley. .7 Preserve a backyard area between the house and the garage, maintaining the general proportion of built mass to open space found within the area. 2.2 Streetscape and Landscape The overall character of the historic districts is defined by more than the buildings. Landscape features of the streetscape, such as the pattern of street trees and planting strips between the sidewalk and the curb, form a significant part of the historic character of an area. Similarly, traditional landscape designs help to unify the district visually. Lawns and low plantings define open spaces between the street and the houses. Traditionally, few front yard fences or landscaping materials obscured the view of the building from the street. Those traditional patterns should be maintained as the districts continue to evolve. GUIDELINES .1 Maintain the established spacing pattern of street trees. .2 Preserve street trees whenever possible. .3 When a tree must be removed, or where there is a gap in the rhythm of street trees, install new street trees in locations that continue to express the established rhythm. .4 Maintain the tree-planting strip as a lawn area. The planting strip (the area between the curb or street and the sidewalk) is traditionally simple, consisting of grass or low ground cover along with regularly spaced street trees. Appropriate:  Grass or low ground cover and trees. Inappropriate:  Extensive areas of hard surface  Elevated planting borders and bushes 2.1.3 Traditionally, the primary building entrance faced the street. The lack of a front entrance on this home disrupts the character of the street. 2.2.4 Grass, low ground cover, and evenly spaced street trees are appropriate for the area between the street and the sidewalk. 25 GENERAL DESIGN GUIDELINES  Edging materials such as timber, railroad ties or masonry, except where there is historic precedent. .5 Provide a front yard that is landscaped in a traditional manner with traditional materials.  Avoid replacing sod with concrete or any hard surface.  Edge areas with natural materials such as stone.  Locate planting beds in traditional areas such as around foundations and along walkways.  The use of railroad ties in landscaping is a recent design approach that is not permitted. .6 Avoid landscaping that has the potential for damaging a historic structure, such as climbing ivy or trees planted too close to a building. .7 Where existing retaining walls are important to the character of the site they should be preserved and incorporated into new landscape features.  Tall, plain concrete retaining walls are inappropriate.  Regrading and the introduction of new retaining walls is inappropriate. 2.3 Alleys The alleys in historic districts were traditionally used for secondary access to the houses, for deliveries, and as storage places for horses and buggies, and later, for cars. A view of the backyards from the alleys was maintained. While today's alleys have evolved into use as pedestrian paths for jogging, bicycling and dog walking, they still contribute to the historic character of the neighborhood. They are typically minimally paved. Along the alleys are historic accessory buildings of various shapes and sizes including barns, chicken coops, sheds and small garages. This variety contributes to the general feeling of human scale in the alleys. GUIDELINES .1 Maintain alley access for parking and retain the character of alleys as clearly secondary access to properties. .2 Retain and preserve the variety and character found in the existing historic accessory buildings along the alleys. .3 The use of historically proportioned materials for building new accessory buildings contributes to the human scale of 2.2.7 Retaining walls are typically stone or brick. Plain concrete is ii 2.3.2 Typical alleys are unpaved and characterized by a variety of small- scale accessory structures and access to parking. 26 SITE DESIGN 27 the alleys. For example, narrower lap siding and smaller brick are appropriate. .4 Structures that were constructed after the period of significance but are still more than 50 years old and contribute to the variety and character of the alleyway should be retained. .5 Maintain adequate spacing between accessory buildings so that the view of the main house is not obscured, and the alley does not evolve into a tunnel-like passage. .6 Generally, paving alleys in historic districts alters the historic character and is inappropriate.  If paving is necessary, a paving material that preserves the utilitarian character of the alley is appropriate.  The preferred surface is a permeable, soft-edged material such as recycled asphalt, that will control drainage and dust.  In problem areas with persistent potholes and/or drainage problems, solutions such as regrading and adding pea gravel should be used. .7 Lighting in alleys should be low wattage and focused downward. See also, Section 8.4 Lighting. 2.4 Parking and Driveways Historically, private parking was limited to the rear of the lot with access from the alley. There are instances where curb cuts have been added in the front yards, but these are generally later alterations and do not represent traditional parking patterns. GUIDELINES .1 Maintain the traditional pattern of parking at the rear of the lot. .2 Access to parking should be from the alleys whenever possible. .3 Parking in the front yard is inappropriate. .4 New curb cuts from the street are inappropriate. When adding a garage or significantly altering an existing garage on the alley any front curb cut should be vacated and closed. 2.4.1 / 2.4.2 Parking should be provided at the rear of the lot and accessed by an alley whenever possible. X STREET ALLEY 27 GENERAL DESIGN GUIDELINES .5 The visual impact of parking for multi-family and commercial uses should be minimized. Common approaches include separating parking into small clusters, screening with buildings or landscaping, and the use of small accessory structures. .6 Historically appropriate paving materials, such as flagstone or brick, can be used to visually break up larger parking areas. .7 Paving driveways or garage access areas with asphalt or concrete gives a modern look and is generally inappropriate, particularly when adjacent to unpaved alleys. Flagstone or brick wheel strips are the preferred alternative. 2.5 Sidewalks Many of Boulder's older neighborhoods were originally paved with flagstone or aggregate concrete. These original walkway materials are important elements and contribute to the historic character of the neighborhood. The traditional pattern of walkways perpendicular from the public sidewalk to the front porches or main entries of the houses provides unity to the streetscape. New sidewalks must meet the Americans with Disabilities Act requirements. GUIDELINES .1 Retain and preserve original sidewalk materials where they exist. If replacement of a deteriorated section is necessary, match the original section or element in location, pattern, spacing, dimensions, materials and color.  Replace flagstone with flagstone.  Replace concrete with concrete. However, if the block- face is predominantly paved with flagstone, replacing concrete portions with flagstone is appropriate. .2 New walkways should be designed to be compatible in location, pattern, spacing, dimensions, materials and color with existing walkways that contribute to the overall historic character of the area.  Walk design should be simple and traditional, reflecting the neighborhood and period of construction.  Flagstone or traditional aggregate concrete is encouraged. 2.4.7 This new garage is accessed by flagstone wheel strips 2.5.1 Typical sidewalks are concrete or flagstone and simple in design. 28 SITE DESIGN 29 .3 Provide a walkway from the street to the primary front entrance of the building. The walkway should generally be perpendicular to the sidewalk. 2.6 Fences The appearance of the house from the sidewalk, street, and alley contributes to an area’s character. Historically, fences were not common in Boulder. Where they existed they were very open, low, and used to delineate space rather than to create walled-off privacy areas. Rear and side yard fences were built low enough so neighbors could talk to each other over them. The fences could be easily seen through and were built of woven wire (not chain-link), wrought iron, or painted or opaque stained wood pickets. Elaborate wrought iron and cast iron fences were typically found only on lots with large or grand homes. GUIDELINES .1 Retain and preserve historic fences that contribute to the historic character of the site or district whenever possible. Repair deteriorated fence components rather than replace them. .2 Where fences were not traditionally found in the front yard and where the streetscape character is defined by open front yards, the introduction of new fences in the front yard is inappropriate. .3 Introduce compatible new fences of traditional materials only in locations and configurations that are characteristic of the historic district. New fencing should reflect the character of historic fences in height, openness, materials, and finish. .4 Generally, historic fences were constructed of wrought iron, wood pickets, or woven wire with an open appearance and a scale that related to the main building. Cedar stockade fences or block walls are inappropriate. .5 Generally, historic wood fences were painted or opaque stained. Transparent stains and unfinished wood are generally inappropriate. The side of the fence facing the street, alley, and/or sidewalk must be finished. .6 Front and rear fences should have some degree of openness and spacing of slats so that the main structure on 2.6.2 Many of the historic districts are characterized by open front yards. Adding new front yard fences in such areas is generally inappropriate. 2.6.4 Wrought iron and cast iron fences were typically found only on lots with large or grand homes. 29 GENERAL DESIGN GUIDELINES the site is visible from the street or alley. Solid wood fencing along the rear of a lot obscures much of the irregularity and variation that defines the essential character of an alley and creates an inappropriate "tunnel" effect. Rear and side yard fences below 5 feet in height with a minimum of 1" spacing between the pickets can be reviewed at staff level. .7 Where appropriate, fences in the front yard should be no more than 36 inches high. This low height should be maintained along the side yard as far as necessary to maintain an unobstructed view of the building's main architectural features, at least to the front elevation of the house and/or porch. At that point, the fence may become gradually higher and less open. .8 Side yard fences were typically located behind the main house, not in the front yard. Where side yard fences do extend into the front yard, they should be low and open with a gradual transition in height toward the rear yard. The portion of the side fence that extends beyond the front elevation of the building should not exceed a maximum of 36 inches in height. 2.6.7 This is an appropriately open and low front yard fence. 2.6.6 This front yard fence is inappropriate for both its height and lack of openness. 2.6.8 This side yard fence gradually transitions from the rear to the front. 30 SITE DESIGN 31 2.7 Pools Pools (including hot tubs and spas) were not traditionally part of the fabric of historic districts during their periods of significance. In many cases, the introduction of these structures may be so detrimental to the character of the site or the streetscape that such construction will be inappropriate. The following guide describes pool structures’ level of appropriateness: - Lap pools May be appropriate - Hot tubs/spas May be appropriate - In ground pools Rarely appropriate - Above-ground pools Not appropriate Spas and narrow lap pools may be appropriate depending on their placement and style. Above ground pools are always inappropriate. Although introduction of an in-ground pool is generally discouraged for most sites, there may be circumstances where the proposed installation could be acceptable. This may occur when the property and the surrounding lots are large enough to provide a sufficient buffering distance from neighboring properties and where proximity to and visibility by all public rights-of-way are minimal. In those instances, the following guidelines may be employed. When site suitability is established, pool design and associated paving, patios, structures and/or mechanical equipment, should be sensitive to and compatible with the overall historic character of the property and/or of the district as a whole. The impact of contemporary site features or equipment such as pools and associated features can sometimes be diminished through careful siting and screening. It is strongly recommended that the property owner engage surrounding property owners to discuss their design and pool location as the introduction of a pool and its appurtenant structures could have an impact. GUIDELINES .1 General  Pools and associated features should be located in an inconspicuous location so as not to be visible from a public right-of-way.  Pools and associated features should not obscure the view of or negatively impact any contributing buildings or features on the site. 31 GENERAL DESIGN GUIDELINES  Above-ground pools are not appropriate; in-ground pools should be designed to be unobtrusive. .2 Siting  Pools should be constructed in rear yards only and are generally inappropriate in side yards or front yards.  On corner lots, pools should be located at the portion of the rear yard farthest from the public rights-of-way. It may not be possible to locate a pool on a corner lot in a way that is not visible from a public right-of-way.  Pools should be designed and located so as to allow for future removal without damage to the historic property.  A back yard planted area should be preserved when locating the pool, maintaining the appropriate proportion of paving and other hardscape to planting on the property. .3 Fencing and Screening  Fences, including required security fencing, will be reviewed as part of the overall project and should be consistent with the General Design Guidelines and applicable district-specific design guidelines.  Chain link fencing is generally inappropriate.  Vegetative screening should be indicated on project landscape plans and should be maintained. .4 Materials & Colors  Patios and decks surrounding the pool should be of materials such as stone or brick.  Pool finishes and colors (including interior liner, tile, & pool covers) should be subdued. .5 Lighting Lighting for swimming pools should be low intensity and beneath the surface of the water or at ground level. .6 Grading Grading modifications will be reviewed as part of the overall project and should meet the General Design Guidelines and applicable district-specific design .7 Paving, decks, & patios  Paving, decks, and patios surrounding the pool area will be reviewed as part of the overall project and should be consistent with the General Design Guidelines and applicable district-specific design guidelines. 32 SITE DESIGN 33  Paving and patios surrounding the pool should be limited in dimension and permeable to the greatest extent possible. .8 Pool & Spa Mechanical Equipment  Mechanical equipment should be located inconspicuously so as not to be visible from the public right-of-way.  Mechanical equipment should be located at or below ground level and shall be screened through fencing or landscape screening. Landscape screening should be indicated on project plans and maintained. 33 CITY OF BOULDER LANDMARKS BOARD ALTERATIONS 34 ALTERATIONS 3. ALTERATIONS The difference between “alteration” and “addition” (section 4) is in the magnitude of change to the original structure. Typically, an alteration is on a smaller scale than an addition. It usually involves elements such as adding dormers, decks, and windows. An addition usually means adding more square footage and/or external walls. As with an addition, an alteration should preserve and complement the historic character of the structure. It should not replicate but should be distinguishable from and simpler in design than any historic element. For example, an added window would not have the elegantly carved frames of a historic window. In general, simpler designs are the most successful. 3.1 Roofs, Skylights, and Solar Panels The roof is one of the primary character-defining features of a historic building, and the repetition of similar roof types creates part of the visual consistency that defines a historic area. Alterations or additions to roofs must be given careful consideration to ensure that they do not compromise the integrity of the historic structure. Typical roof shapes are gabled or hipped. Shed roofs sometimes occur on historic additions and accessory structures. Buildings within a district may have a combination of these roof types. GUIDELINES .1 Retain and preserve the original roof form of a historic structure.  Maintain the roof form, slope, height, and orientation to the street.  Preserve the original depth of the overhang along the eaves.  Any alterations to a roof should be compatible with the form, pitch, plate height and massing of the historic roof.  Raising the roof to accommodate a full or partial upper story addition is inappropriate – consider the addition of a dormer instead. .2 Preserve the character of the original roofing and its details.  Although historical accuracy in roofing materials is not required, attempt to preserve the type, unit scale, and HIPPED GABLE SHED TYPICAL ROOF FORMS Winter & Company 35 GENERAL DESIGN GUIDELINES texture of the original roofing. In some circumstances, the roofing material is an important architectural feature that should be preserved. For example, metal roofs should remain metal; tiled roofs should remain tiled.  Boulder has an ordinance that requires the phasing out wood shingle roofs. Dimensional, composition shingles are an appropriate replacement.  Avoid removing historically important roofing or wood trim that is in salvageable condition. Retain and repair roof detailing such as brackets, cornices, parapets, bargeboards and gable-end shingles. .3 Skylights that are installed on a historic roof should be as unobtrusive as possible and not visible from a public street. Flat skylights that blend with the roof are most appropriate. Sculptural or bubble-type skylights are not appropriate. Also see Guideline 8.3.4. .4 Minimize the visual impact of solar collectors. Also see Guideline 8.3.4.  The use of energy-efficient and energy-conserving materials is encouraged, but they should not compromise the historic integrity of the building.  Solar collectors should not alter the existing profile of the roof nor be highly visible, particularly from the front of the house. They should be mounted flush on rear-facing roofs or placed on the ground in an inconspicuous location. .5 Roof appurtenances such as swamp coolers, TV antennas, and satellite dishes should be installed so that they are not visible from the street and do not damage or obscure historic features. Also see Guideline 8.3.4. 3.2 Roof Decks and Balconies Roof decks are deck areas above the first floor that are contained completely or partially in a roof mass. Balconies are railed or balustraded platforms that project from the building. Second story roof decks or balconies are characteristic of only a few architectural styles found in Boulder. They may be compatible additions, however, if located on the rear and if they are integrated into the primary structure. Second story roof decks or balconies are not appropriate for free-standing accessory buildings and garages. Any decks or balconies above the second story are inappropriate unless based on historic precedent. 3.1.5 Mechanical equipment, such as coolers, should not be visible from the street. 3.1.3 Bubble-type skylights are inappropriate, especially when visible from the street. 36 ALTERATIONS GUIDELINES .1 Locate roof decks or balconies on the rear, not on the front, of the building. Front roof decks or balconies are appropriate only if recreating a documented historic element. .2 Integrate the roof deck or balcony into the structure either by setting it into the building or by incorporating it into the roof structure. .3 Avoid cantilevered projections from the building, and use appropriately scaled brackets or supports. .4 While current code requirements must be met, new railings should be as close as possible to historic heights. In addition, sensitive design may give the appearance of the lower railing heights found on historic structures. 3.3 Decks Decks are modern expressions of porches that were not found on historic buildings. Great care needs to be taken in designing decks to fit into the historic character of the house. The design elements must respect the historic character as to size, materials, railing detail, intrusion into spaces between buildings, and materials. Because decks are not traditionally found on historic structures, they should be avoided or their appearance should be minimized. Decks should be subordinate to the house in terms of scale and detailing. GUIDELINES For second story decks, see 3.2 Roof Decks and Balconies. .1 First floor decks are inappropriate in the front of a house. Locate a first floor deck to the rear of a building. .2 While current code requirements must be met, new railings should be as close as possible to historic heights. In addition, sensitive design may give the appearance of the lower railing heights found on historic structures. .3 Unpainted redwood is inappropriate; decks should be painted or stained to match the existing building. .4 Materials with a synthetic look and/or feel should be avoided. 3.2.2 This rear roof deck is appropriately integrated into the roof. 37 GENERAL DESIGN GUIDELINES 3.4 Porches Front porches are a common and important visual element of many historic building styles. The porch roof is generally supported by freestanding columns or by columns resting on a masonry wall. Wood railings are anchored with masonry or wood balustrades. A porch is generally open with the facade of the house plainly visible. GUIDELINES .1 Original porches should be preserved. .2 Deteriorated original porches and porch elements, such as railings, balusters and columns, should be repaired or replaced, following recognized preservation methods so that the character of the porch is not compromised. .3 Maintain the height, detail and spacing of the original balustrade if replacing, extending or adding balustrades. .4 Enclosing a front porch negatively impacts the visual character of both the individual house and the streetscape and is inappropriate. .5 If a rear or side porch is to be enclosed, the following guidelines apply:  Maintain the sense of openness, scale, proportion, and separation from the structure of the house. The enclosure should not obscure the main architectural details of the porch or house.  Keep the design and materials as simple as possible rather than trying to match the building facade. .6 Rebuilding a missing original front porch is encouraged if evidence of the original porch can be documented. .7 The introduction of new porches that were not present historically is inappropriate on individual landmarks and buildings that are contributing to a historic district. .8 Porches on new buildings or on non-contributing buildings should be compatible with the architecture of the building, incorporating traditional scale and proportions with updated design details. .9 Large, two-story tall porches are inappropriate for front facades unless present historically. Front porches are key character- defining features of both individual buildings and the streetscape. 38 ALTERATIONS 3.5 Dormers Dormers are traditional roof elements that either extend the space under the main roof or serve as decorative elements to the main roof. They generally follow the pitch and form of the main roof and are always secondary to the main roof massing. The introduction of dormers may dramatically change the building's appearance, and therefore may not be appropriate in all circumstances. GUIDELINES .1 Existing dormers are important character-defining features of a building and should be preserved, particularly those that are most visible from the street. .2 Deteriorated elements should be repaired or replaced, following recognized preservation methods. .3 Existing dormers should not be enlarged or altered in any way that changes their secondary relationship to the main roof. .4 The size, scale, and style of new dormers should be compatible with existing dormers on the structure. The form of roof dormers should be compatible with the main roof form. .5 Dormer windows should be similar in proportion to first and second floor windows but smaller. .6 New dormers must be subordinate to the main roof in terms of mass, scale and height. Notwithstanding the fact that one large dormer may give the greatest usable space within the roof form, smaller dormers are usually the most appropriate. Often two small dormers are more appropriate than one large dormer. .7 Dormer ridgelines must be lower than the main roof. 3.5.4 Dormer forms should match roof forms; e.g. gabled roofs should have gabled dormers and hipped roofs should have hipped dormers. 3.5.6 / 3.5.7 The size of these dormers overwhelms the main roof and the ridgelines are even with, rather than below, the main roof. 39 GENERAL DESIGN GUIDELINES 3.6 Exterior Materials: Walls, Siding, and Masonry Brick, stone, horizontal wood-lapped siding, stucco, and wood shingles are common finish materials found in historic districts and on historic structures. Over the years, the materials used in residential construction have not changed dramatically, but the scale of materials has become larger. Narrower lap siding, smaller brick and shingles used alone or in various combinations often distinguish older homes from newer ones. Brick and stone masonry were traditionally left natural while wood surfaces were painted. GUIDELINES .1 Original historic finish materials should be preserved and repaired.  Unpainted masonry surfaces, particularly those with historical significance, should not be painted.  When feasible, remove newer materials that have been applied over historic finishes and that have not achieved historic significance in their own right. Removal of non-historic materials such as stucco or permastone must be tested to assure that the original material will not be damaged in the process.  When repairing masonry use appropriate mortar, i.e., one that is softer than the surrounding masonry. .2 New finish materials should be compatible with, but not seek to replicate, original finish materials.  Use materials that are similar in scale, proportion, texture and finish to those used historically.  Use authentic materials - materials made to look like other materials, such as concrete that is scored to look like brick, are not appropriate. Historic materials such as wood siding, stone, brick and dimensional shingles help establish human scale. 40 ALTERATIONS 3.7 Windows, Storm Windows, and Shutters Windows, the elements that surround them, and their relationship to one another are one of the most important character-defining elements of a historic building and should be preserved. Improper or insensitive treatment of the windows on a historic structure can seriously detract from its architectural character. The relative importance of a window depends on three factors: the location of the window on the building, the historic significance of the window, and its condition. Windows on elevations visible from public ways, particularly the façade, are especially important. A window that has a high level of historic significance, regardless of its location, may also be very important to the historic integrity of the building. The replacement of historic windows or components including glass, should be considered only as a last resort. At times, property owners consider replacement of their historic windows as a way of improving energy efficiency. Research indicates that, in most cases, the energy efficiency of an old window can be increased to that of a thermal pane replacement window by weather- stripping, insulation of weight pockets, and the application of an interior or exterior storm system. While the energy loss of a building may be reduced by replacing or repairing historic windows, windows are only one factor in the building’s energy usage. It is strongly recommended that a comprehensive energy audit be undertaken to identify areas for improvement. To increase a building’s energy efficiency, a combination of air sealing, additional wall and ceiling insulation, and the adjustment of mechanical systems is generally more effective than focusing only on the repair or replacement of a window. For more information regarding energy efficiency and energy audits for historic buildings, please contact the Office of Environmental Affairs at www.environmentalaffairs.com GUIDELINES Protection of Historic Windows .1 Retain and preserve existing historic windows, including their functional and decorative features, such as frames, glass, sashes, muntins, sills, heads, moldings, surrounds and hardware. Because windows near the façade are particularly critical to the character of historic buildings, their protection may supercede the protection of historic windows elsewhere. In some cases, it may be appropriate to use window elements from rear or side elevations to repair those on the front. 41 GENERAL DESIGN GUIDELINES .2 Preserve original window locations; do not move windows from their historic placement. .3 Repair rather than replace the functional and decorative features of original windows through recognized preservation methods. If replacement of a feature is necessary, replace only the deteriorated feature in kind rather than the entire unit, matching the materials, design and dimensions of the original. Retrofit of Historic Windows .4 In some cases, retrofitting historic windows to make them more energy efficient may be appropriate as part of a building rehabilitation program. Typically a window retrofit preserves most or all of the historic wood, glass, or metal components and consists of insulating weight pockets and complete weather stripping of its sash and frames. If a window retrofit calls for the replacement of single pane glass, it is important to determine that the work will not compromise the historic character of the building or the district in which it is located. Historic glass is typified by its “wavy” uneven surface which can be an important character defining feature of a window and the historic building as a whole. Depending upon its location on the building, the importance to the window itself, and relative condition, the replacement of historic glass may be inappropriate. • Retrofitting historic true divided light windows with thermal-pane glass is inappropriate on primary or secondary elevations. • Retrofitting historic windows on primary elevations is rarely appropriate unless the glass has been replaced with non-historic glass. • The dimensions and relationship of replacement glass to the stiles, rails, and muntins must closely match those of the unimproved window. The depth of the face of the sash to the plane of glass is a character defining feature. • The retrofit of historic sash with visibly tinted or reflective glass is inappropriate. • The introduction of weather stripping, insulation, or materials to improve the operation of historic windows is among the most effective and least costly steps that can be taken to improve energy efficiency and convenience of operation. 42 ALTERATIONS Window Replacement .5 The replacement of historic windows should only be considered as a last resort if the fabric of the window is deteriorated beyond repair. However, if the property owner wishes to request a landmark alteration certificate to replace windows on a contributing or individually landmarked building, the steps as outlined in the Historic Window and Door Replacement/Retrofit Guidelines must be followed. .6 The location of the window(s) proposed for retrofit or replacement is important in assessing their significance to a historic building. In general, the more important the elevation where the window is located, the less likely that retrofit or replacement will be appropriate. Elevations will be categorized as primary, secondary or tertiary, using the methodology set out in the Window & Door Replacement Application and Survey. • Replacement of intact historic windows on primary elevations is rarely appropriate. • Replacement of intact historic windows on secondary elevations is generally inappropriate. • Replacement of intact historic windows on tertiary elevations can occur provided it does not compromise the historic integrity of the building. .7 The historic significance of the windows proposed for replacement must also be assessed. In general, the more significant a window is to the building as a whole, the less likely that a retrofit or replacement will be appropriate. The appropriateness of a window replacement will be determined, in part, based upon characterization of the window as either ‘Very Historically Important’, ‘Historically Important’, or ‘Non-Historic’ (See Definitions). 43 GENERAL DESIGN GUIDELINES WINDOW & DOOR SIGNIFICANCE Very Historically Important Historically Important Non-Historic Primary Elevation Repair Repair Replacement allowed Secondary Elevation Repair Reviewed case by case Replacement allowed Tertiary Elevation Repair Replacement allowed Replacement allowed .8 The condition of the window must be evaluated prior to determining whether the window or door may be repaired or replaced. The condition is to be determined by assessing its elements individually. The assessment must be completed through the use of a survey that identifies the extent of deterioration in each window and determines whether the windows may be repaired, retrofitted, or replaced. The survey form documents the existing condition for the window and identifies which features will be repaired and which will possibly be replaced. .9 If, through the Window & Door Application & Survey (available as a separate document), it is determined that the window sashes are too deteriorated to repair (Class III & IV), but the window frames are salvageable, then sashes only should be replaced to match the original per the Retrofit or Replacement Section. .10 If, through the Window & Door Application & Survey, it is determined the window may be replaced (Class III & IV), the window opening itself should be carefully preserved. It should not be made larger or smaller to accommodate a differently sized window. .11 If, through the Window & Door Application & Survey, it is determined the window may be replaced (Class III & IV), the same material as was the original is most appropriate; 44 ALTERATIONS however, other materials may be considered if the operation, dimension, profile, durability, and finish are the same. Synthetic materials are generally inappropriate. Synthetic materials rarely duplicate the surface texture, reflective and detail qualities of original materials. .12 If a window that is divided into several panes of glass must be replaced, a similar true-divided-light window that matches the dimensions, profile and detailing of the original is most appropriate. High quality simulated- divided-light windows may be allowed if they maintain the muntin size of the original window. Snap-in muntins or other inauthentic architectural details are inappropriate. .13 Historic steel windows are character-defining features on some buildings in historic districts. Because windows manufactured from other materials generally cannot match the thin profiles of steel, replacement is generally inappropriate. .14 If the existing condition of the window(s), as documented by a Window & Door Survey, indicates Class III or IV damage or deterioration, then the window(s) may be retrofitted or replaced. All retrofitted or replacement windows must match the historic feature as closely as possible. Windows in New Construction .15 Windows in additions and new structures should reflect the window patterns and proportions of the existing structure and the district and utilize similar materials. For elevations visible from public streets, the relationship of solids to voids should also be compatible. .16 Windows should be trimmed with materials similar in scale, proportion, finish, and character to those used traditionally. .17 Openings should indicate floor levels, and generally should not occur between floors. .18 Symmetry or asymmetry of openings should be maintained. .19 Odd window shapes such as octagons, triangles, and diamonds are generally inappropriate. Shutters and Storm Windows 3.7.15 / 3.7.19 The relationship between the amount of window and wall in this home is out of proportion with traditional designs. The odd shaped windows at the roof peak are also incompatible with historic patterns. 3.7.12 True-divided light windows have individual panes of glass separated by muntins. While some high- quality simulated-divided light windows may be acceptable as replacements in some cases, true- divided light windows are most appropriate. 45 GENERAL DESIGN GUIDELINES .20 Use shutters only if appropriate to the style of the house. The introduction of exterior shutters to a historic building, when there is no evidence that shutters were a historic feature of the house, is inappropriate. .21 Reintroducing missing shutters is encouraged if evidence of the original shutters can be documented. .22 While shutters need not be operable, they should be sized to maintain the appearance of operability. .23 Improving the energy efficiency of older windows can often be addressed through simple repairs. Storm windows or interior energy panels are alternatives to window replacement. Wood storm windows are preferred. Metal storm windows may be appropriate if the frames match the proportions and profile of the original windows and if the frames are durably coated so that raw metal is not visible and fading and chalking are minimized. Vinyl storm windows are generally inappropriate. Interior installation is preferred. 46 ALTERATIONS 3.8 Doors and Storm Doors Front doors and primary entrances are among the most important elements of historic buildings. The original size and proportion of a front door, the details of the door, the door surround, and the placement of the door all contribute to the character of the entrance. Property Owners may wish to replace their historic doors to improve energy efficiency. Research indicates that, in most cases, however, the energy efficiency of an old door can be increased to that of a new replacement door by weather-stripping and the application of an interior or exterior storm door system. However, if a property owner wishes to request a landmark alteration certificate to replace doors on a contributing or individually landmarked building, the steps as outlined in the historic Window and Door Replacement/ Retrofit Application Guidelines must be followed. GUIDELINES .1 Whenever possible, retain and preserve all original doors and door openings. The location of the door(s) proposed for retrofit or replacement is important in assessing their significance to a historic building. In general, the more important the elevation, the less likely that replacement of a historic door will be appropriate. Elevations will be categorized as primary, secondary, or tertiary, using the methodology set out in the Window & Door Replacement Application and Survey. • Replacement of intact historic doors on primary elevations is rarely appropriate. • Replacement of intact historic doors on secondary elevations is generally inappropriate. • Replacement of intact historic doors on tertiary elevation can occur provided it does not compromise the historic integrity of the building. .2 The historic significance of the door(s) proposed for replacement must also be assessed. In general, the more significant a door is to the house as a whole, the less likely that a retrofit or replacement will be appropriate. The appropriateness of a door replacement will be determined, in part, based upon characterization of the door as either ‘Very Historically Important’, ‘Historically Important’, or ‘Non-Historic’. (See Definitions). .3 The condition of the door(s) shall be evaluated prior to determining whether the door(s) should be repaired or replaced. The condition is to be determined by assessing An appropriate door in terms of size, proportion and detailing. 47 GENERAL DESIGN GUIDELINES its elements individually. The assessment will be completed through the use of a survey that is intended to identify the extent of deterioration in each doors and to determine whether the door should be repaired, retrofitted, or replaced. The survey form documents the existing condition for the door and identifies which features will be repaired and which will possibly be replaced. .4 Retain and preserve the functional, proportional and decorative features of a primary entrance. These features include the door and its frame, sill, head, jamb, moldings, and any flanking windows. .5 Historic hardware, hinges, locksets, and knobs are door features that are significant and should be preserved. .6 Repair damaged original doors and door assemblies whenever possible following recognized preservation methods. .7 If, through a Window & Door Application Survey replacement is found to be appropriate, the replacement door should match the original as closely as possible. If documentation of the original door is not available, then the appearance of the replacement door should be based on original doors on similar historic structures. .8 Replace wood doors with wood doors. Synthetic materials are generally inappropriate. Synthetic materials rarely duplicate the surface texture, reflective and detail qualities of original materials. The use of materials matching the historic material is recommended. .9 If energy conservation and heat loss are a concern, consider using a storm door instead of replacing a historic entry door. Generally, wood storm doors are most appropriate. A metal storm door may be appropriate if it is simple in design and if the frame is durably coated so that raw metal is not visible and fading and chalking are minimized. Vinyl storm doors are generally inappropriate. .10 Doors in additions and new structures should reflect the proportions (height and width) of doors in the existing structure and/or the district. 3.8.10 The modern detailing on this door would be inappropriate for most homes in Boulder’s historic districts. 48 ALTERATIONS .11 Doors should be trimmed with materials similar in scale, proportion, finish, and character to those used traditionally. 49 CITY OF BOULDER LANDMARKS BOARD ADDITIONS TO HISTORIC STRUCTURES 50 GENERAL DESIGN GUIDELINES 4. ADDITIONS TO HISTORIC STRUCTURES This section applies to buildings that are individual landmarks or are within a historic district and have been identified as Contributing, Contributing-Restorable, or Significant Newer. (see p. 7 and Glossary). Additions to non-historic structures are considered in Section 5. While the guidelines in this section do not specifically apply to those properties, they do represent design principles that should be considered in any addition. It is normal for buildings to evolve over time as additional space is needed or uses are accommodated. New additions within the historic districts are appropriate as long as they do not destroy historic features, materials, and spatial relationships that are significant to the original building and site. They also must be distinguishable from the historic architecture. New additions should not compromise the integrity of the original structure or site, whether through direct destruction of historic features and materials or indirectly through their location, size, height or scale. Additions should be compatible with, but discernible from, the historic architecture. When the original design is duplicated the addition is indistinguishable and the historic evolution of the building becomes unclear. Conversely, when design elements contrast too strongly with the original structure the addition will appear visually incompatible. The appropriate location of an addition to an existing building will depend on the character of the existing building and its site, adjacent buildings, and the area as a whole. While every site is unique, generally additions are most appropriate at the rear of the structure. The addition should be designed and located so that significant site features, including mature trees, are not lost. An addition should not overpower the site or dramatically alter its historic character, and should be subordinate to the existing structure. The primary focus in reviewing additions will be on aspects of new construction that are visible from public streets. The guidelines will be applied most stringently to these publicly visible areas. More flexibility will be allowed for rear elevations and other areas largely screened from public view. 51 ADDITIONS TO HISTORIC STRUCTURES 4.1 Protection of Historic Structures and Sites The primary concern of the Landmarks Board in reviewing additions to historic structures is the protection of the existing structure and the character of the site and district. GUIDELINES .1 Construct new additions so that there is the least possible loss of historic fabric and so that the character-defining features of the historic building are not destroyed, damaged, or obscured. .2 New additions should be constructed so that they may be removed in the future without damaging the historic structure. .3 It is not appropriate to construct an addition that will detract from the overall historic character of the principal building and/or the site, or if it will require the removal of significant building elements or site features. 4.2 Distinction from Historic Structures All additions should be discernible from the historic structure. When the original design is duplicated the historic evolution of the building becomes unclear. Instead, additions should be compatible with the historic architecture but clearly recognizable as new construction. GUIDELINES .1 Distinguish an addition from the historic structure, but maintain visual continuity between the two. One common method is to step the addition back and/or set it in slightly from the historic structure. Every project is different and successful designs may incorporate a variety of approaches. .2 Do not directly copy historic elements. Instead, interpret historic elements in simpler ways in the addition. .3 Additions should be simpler in detail than the original structure. An addition that exhibits a more ornate style or implies an earlier period of architecture than that of the original is inappropriate. .4 The architectural style of additions should not imitate the STREET 4.2.1 Additions can be distinguished from the original building by being set in, allowing the corners of the historic building to be visible. 4.2.2 The upper photo shows a historic window. The lower photo shows a simplified interpretation of the design on an addition to the home. 52 GENERAL DESIGN GUIDELINES historic style but must be compatible with it. Contemporary style additions are possible, but require the utmost attention to these guidelines to be successful. The use of two distinct historic styles, such as adding Tudor-style half-timbering to a Classic Cottage, is inappropriate. 4.3 Compatibility with Historic Structures Introducing new construction that contrasts sharply with an existing historic structure or site detracts from the visual continuity that marks our historic districts. While additions should be distinguishable from the historic structure, they must not contrast so sharply as to detract from the original building and/or the site. Additions should never overwhelm historic structures or the site, in mass, scale or detailing. GUIDELINES .1 An addition should be subordinate to the historic building, limited in size and scale so that it does not diminish or visually overpower the building. .2 Design an addition to be compatible with the historic building in mass, scale, materials and color. For elevations visible from public streets, the relationship of solids to voids in the exterior walls should also be compatible. .3 Adding a partial or full story to the historic portion of a historic building is rarely appropriate. .4 Reflect the original symmetry or asymmetry of the historic building. .5 Preserve the vertical and horizontal proportion of a building's mass. 4.4 Compatibility with Historic Site and Setting Additions should be designed and located so that significant site features, including mature trees, are not lost or obscured. The size of the addition should not overpower the site or dramatically alter its historic character. GUIDELINES .1 Design new additions so that the overall character of the site, site topography, character-defining site features and 4.3.4 / 4.3.5 This addition, while subordinate to the historic building, skews the building’s original symmetry and vertical proportion. 53 ADDITIONS TO HISTORIC STRUCTURES trees are retained. .2 Locate new additions on an inconspicuous elevation of the historic building, generally the rear one. Locating an addition to the front of a structure is inappropriate because it obscures the historic facade of a building. .3 Respect the established orientation of the original building and typical alignments in the area. .4 Preserve a backyard area between the house and the garage, maintaining the general proportion of built mass to open space found within the area. See Guideline 2.1.1. 4.5 Key Building Elements Roofs, porches, dormers, windows and doors are some of the most important character-defining elements of any building. As such, they require extra attention to assure that they compliment the historic architecture. In addition to the guidelines below, refer also to Section 3.0 Alterations for related suggestions. GUIDELINES Roofs .1 Maintain the dominant roofline and orientation of the roof form to the street. .2 Rooflines on additions should be lower than and secondary to the roofline of the original building. .3 The existing roof form, pitch, eave depth, and materials should be used for all additions. Dormers .4 If consistent with the architectural style of a historic structure and appropriately sized and located, dormers may be an appropriate way to utilize upper story space. Windows .5 Maintain the proportion, general style, and symmetry or asymmetry of the existing window patterns. .6 Use window shapes that are found on the historic structure. Do not introduce odd-shaped windows such as octagonal, triangular, or diamond-shaped. 4.1.1 / 4.4.2 A series of inappropriate additions to this historic building have completely obscured the front façade and destroyed historic fabric. 4.5.1 The roof form of an addition should generally be the same as the form of the original roof. 54 GENERAL DESIGN GUIDELINES .7 Do not add divided light windows to structures that historically did not have divided light windows. .8 Use materials and construction similar to historic windows. Do not use snap-in mullions. 55 CITY OF BOULDER LANDMARKS BOARD ADDITIONS TO NON-HISTORIC STRUCTURES 56 GENERAL DESIGN GUIDELINES 5. ADDITIONS TO NON-HISTORIC STRUCTURES IN HISTORIC DISTRICTS This section contains guidelines for additions to buildings that have been determined to be non-contributing to a historic district. Non-Contributing buildings include those that, although constructed during the district’s period of significance, have been altered to such an extent that the historic integrity is lost and restoration is not possible. Buildings constructed outside the period of significance and that are not individually significant (Individual Landmarks or Significant Newer) are also considered Non-Contributing. In general, the guidelines for additions to non-contributing buildings are more flexible than those for historic buildings, with the exception of site design guidelines (Section 2.0 Site Design) and the respect for the mass and scale of the district. Projects will be evaluated based on these issues and the overall impact on the character of the district. While non-contributing buildings are not required to follow the guidelines in Section 4.0 Additions to Historic Structures, such projects may benefit from the design principles suggested by them. For substantial alterations to a non-historic building, see Section 6.0 New Structures. Substantial alterations are those that would require issuance of a demolition permit if the building were over 50 years of age. GUIDELINES .1 Follow the guidelines in Section 2.0 Site Design .2 It is not appropriate to construct an addition that will detract from the overall historic character of the district by overwhelming existing buildings in mass and scale. .3 Alterations to non-contributing buildings built in a recognizable architectural style should preserve and respect that style. 57 CITY OF BOULDER LANDMARKS BOARD NEW PRIMARY STRUCTURES 58 GENERAL DESIGN GUIDELINES 6. NEW PRIMARY STRUCTURES New construction within a historic district can enhance the existing district character if the proposed design and its siting reflect an understanding of and a compatibility with the distinctive character of the district. While new construction should fit into the historic character of the district or site, it should not replicate historic styles. Instead, new buildings should relate to the fundamental characteristics of the historic district or landmark site while also conveying a contemporary style. New buildings should not overshadow existing historic structures. Fundamental characteristics to be considered in designing compatible new structures include: site and setting, building size and proportions, materials, and the placement and style of doors and windows. The primary focus in reviewing new structures will be on aspects that are visible from public streets. The guidelines will be applied most stringently to these publicly visible areas. More flexibility will be allowed for rear elevations and other areas largely screened from public view. 6.1 Distinction from Historic Structures The replication of historic architecture in new construction is inappropriate, as it can create a false historic context and blur the distinction between old and new buildings. While new structures must be compatible with the historic context, they must also be recognizable as new construction. GUIDELINES .1 New construction should be a product of its own time. Create compatible contemporary interpretations of historic elements. .2 Interpretations of historic styles may be appropriate if they are distinguishable as new. 6.2 Site and Setting New structures should be designed and located so that significant site features, including mature trees, are not lost or obscured. The size of the new structures should not overpower the site or dramatically alter its historic character. Buildings within historic districts generally display a consistency in setback, orientation, spacing and distance 6.1.1 A contemporary interpretation of a historic element. 59 NEW PRIMARY STRUCTURES between adjacent buildings. Therefore, the compatibility of proposed new construction will be reviewed to ensure that these elements are maintained. GUIDELINES .1 Conform to the design guidelines found in Section 2.0 Site Design, regarding site and setting in developing a proposed site plan. .2 Design new construction so that the overall character of the site, site topography, character-defining site features and trees are retained. .3 Site new construction to be compatible with surrounding buildings that contribute to the overall character of the historic district in terms of setback, orientation, spacing, and distance from adjacent buildings. .4 New construction should not be significantly different from contributing historic buildings in the district in terms of the proportion of built mass to open space on the individual site. See Guideline 2.1.1. .5 New primary structures should serve as a guide for new accessory structures on the site. Conform to the design guidelines found in Section 7.0 New Garages and Other Accessory Structures. 6.3 Mass and Scale In considering the overall compatibility of new construction, its height, form, massing, size and scale will all be reviewed. The overall proportion of the building's front façade is especially important to consider since it will have the most impact on the streetscape. While new construction tends to be larger than historic buildings, reflecting the needs and desires of the modern homeowner, new structures should not be so out-of-scale with the surrounding buildings as to loom over them. GUIDELINES .1 Design new buildings to be compatible with surrounding buildings that contribute to the overall character of the historic district in terms of height, size, scale, massing, and proportions. 6.2.2 / 6.3.2 The marked building is built outside the range of typical setbacks, occupies a much larger percentage of the lot than typical, and is generally out of scale with surrounding buildings x 60 GENERAL DESIGN GUIDELINES .2 The mass and scale of new construction should respect neighboring buildings and the streetscape as a whole. .3 Historic heights and widths as well as their ratios should be maintained. The proportions of the front façade are particularly important and should be compatible to those of surrounding historic buildings. .4 A new house constructed behind an existing historic house should be of lesser mass and scale than the original structure. 6.4 Materials GUIDELINES .1 Materials should be similar in scale, proportion, texture, finish, and color to those found on nearby historic structures. .2 Maintain a human scale by avoiding large, featureless surfaces and by using traditionally sized building components and materials. 6.5 Key Building Elements Roofs, porches, dormers, windows and doors are some of the most important character-defining elements of any building. As such, they require extra attention to assure that they compliment the historic architecture. In addition to the guidelines below, refer also to Section 3.0 Alterations for related suggestions. GUIDELINES .1 Design the spacing, placement, scale, orientation, proportion, and size of window and door openings in new structures to be compatible with the surrounding buildings that contribute to the historic district, while reflecting the underlying design of the new building. .2 Select windows and doors for new structures that are compatible in material, subdivision, proportion, pattern and detail with the windows and doors of surrounding buildings that contribute to the historic district. .3 New structures should use a roof form found in the district or on the landmark site. 61 NEW PRIMARY STRUCTURES .4 Porches should be compatible in massing and details to historic porches in the district, and should be appropriate to the style of the house. .5 Dormers should be secondary to the main roof and should be lower than the roofline. Oversized dormers are inappropriate. 62 CITY OF BOULDER LANDMARKS BOARD GARAGES & OTHER ACCESSORY STRUCTURES 63 GENERAL DESIGN GUIDELINES 7. GARAGES & OTHER ACCESSORY STRUCTURES Accessory structures include barns, sheds, garages, and outbuildings. Originally accessory structures were used for storage of equipment, animals, or carriages. Generally, these structures have been adapted for the storage of cars. In most cases, accessory buildings were located to the rear of the lot and accessed by alleys. They were subordinate in size and detailing to the primary house. Over time they have emerged as important elements of many lots and alleys in the district. Efforts should be made to protect the eclectic character of alleys. Both additions to existing accessory buildings and new accessory buildings will be evaluated in terms of how they affect the historic character of the individual site and the district as a whole. In the past, larger accessory structures have been allowed than may be appropriate today. 7.1 Existing Historic Accessory Structures A primary concern of the Landmarks Board in reviewing proposed changes in historic districts is the protection of existing historic accessory structures and the character of the site and district. .1 Retain and preserve garages and accessory buildings that contribute to the overall historic character of the individual building site or the district. .2 Retain and preserve the character-defining materials, features, and architectural details of historic garages and accessory buildings, including roofs, exterior materials, windows, and doors. 7.2 New Accessory Buildings New accessory buildings should follow the character and pattern of historic accessory structures. While they should take design cues from the primary structure, they must be subordinate to the primary structure in size, massing, and detailing. Alley buildings should maintain a scale that is pleasant to walk along and comfortable for pedestrians. Location and Orientation .1 It is inappropriate to introduce a new garage or accessory building if doing so will detract from the overall historic 64 GARAGES & OTHER ACCESSORY STRUCTURES character of the principal building and the site, or if it will require removal of a significant historic building element or site feature, such as a mature tree. .2 New garages and accessory buildings should generally be located at the rear of the lot, respecting the traditional relationship of such buildings to the primary structure and the site. .3 Maintain adequate spacing between accessory buildings so alleys do not evolve into tunnel-like passageways. .4 Preserve a backyard area between the house and the accessory buildings, maintaining the general proportion of built mass to open space found within the area. Mass and Scale .5 New accessory structures should take design cues from the primary structure on the site, but be subordinate to it in terms of size and massing. .6 New garages for single-family residences should generally be one story tall and shelter no more than two cars. In some cases, a two-car garage may be inappropriate. .7 Roof form and pitch should be complimentary to the primary structure. Materials and Detailing .8 Accessory structures should be simpler in design and detail than the primary building. .9 Materials for new garages and accessory structures should be compatible with those found on the primary structure and in the district. Vinyl siding and prefabricated structures are inappropriate. .10 Windows, like all elements of accessory structures, should be simpler in detailing and smaller in scale than similar elements on primary structures. See Sections 3.7 and 4.5 for additional direction. .11 If consistent with the architectural style and appropriately sized and located, dormers may be an appropriate way to increase storage space in garages. See Section 3.5 and 4.5 for additional direction. 7.2.2 Parking should be provided at the rear of the lot and accessed by an alley whenever possible. X STREET ALLEY 7.2.5 / 7.2.7 Garages should be subordinate to the primary structure and be complimentary in terms of room form and pitch. 65 GENERAL DESIGN GUIDELINES .12 Garage doors should be consistent with the historic scale and materials of traditional accessory structures. Wood is the most appropriate material, and two smaller doors may be more appropriate than one large door. .13 It is inappropriate to introduce features or details to a garage or an accessory building in an attempt to create a false historical appearance. .14 Carports are inappropriate in districts where their form has no historic precedent. 66 CITY OF BOULDER LANDMARKS BOARD MISCELLANEOUS 67 GENERAL DESIGN GUIDELINES 8. MISCELLANEOUS 8.1 Paint and Paint Colors When renovating a historic building, first consider using the original color scheme. The original paint can often be discovered by careful analysis of samples of original materials. If it is not possible to discern original paint colors, a color scheme should be based on historic precedent within the area. The multiple, bright colors used in San Francisco, for instance, were not used in Boulder. Historically, paint colors were more muted tones than those used today because they depended upon a far more limited source of pigments. Most wood-clad buildings were painted entirely, generally with one base color and one or two additional accent colors on details and trim. For masonry structures, the natural color of the brick or stone was dominant; paint was applied to wood trim elements around doors and windows and in gable ends. As a practical matter, it is suggested that quart samples of the color scheme should be applied to a section of building as a test before making final selection. A color on a 1" x 1" paint chip will look different on a whole house. GUIDELINES .1 Preserve and protect original exterior building surfaces and site features that were painted by maintaining a sound paint film on them. .2 Original materials such as brick and stone that are unpainted should not be painted. .3 When repainting, select paint colors appropriate to the historic building and district. When possible, recreate historic paint schemes based on samples of original materials.  When selecting paint schemes, a good rule of thumb is to use a single body color with a lighter and/or brighter accent color.  Historic paint colors in Boulder are conservative, emphasizing muted shades or tones rather than pure hues. New paint colors should not be bright or garish. 68 MISCELLANEOUS 8.2 Energy Efficiency In 2006, Boulder’s City Council adopted a Climate Action Plan to meet the Kyoto Protocol goals of substantially lower emissions of greenhouse gases. It is the city’s aim to create compatibility between historic preservation and energy efficiency goals. In the historic districts and on individually landmarked buildings it is important to ensure that energy efficiency concerns are addressed in ways that do not damage or diminish the historic character of the building, site or district. It is recommended that before any energy efficiency upgrades are made a comprehensive energy audit is conducted to determine the building’s current energy loss. In historic districts, a variety of energy-conserving site and building features illustrate the sensibility of an earlier era to climate and energy efficiency. Thoughtfully located shade trees buffer residences and sidewalks from the summer sun. Projecting porches provide shaded outdoor space and lessen the impact of the harsh sunlight on the building's interior. Operable windows and shutters allow occupants to control the introduction of sunlight and breezes within the buildings. An understanding of how such historic features enhance energy efficiency is critical to maximizing the energy efficiency of historic buildings. For more information regarding the energy audit program and energy efficiency in historic buildings, please contact the Office of Environmental Affairs at www.environmentalaffairs.com. GUIDELINES .1 Retain and preserve the inherent energy-conserving features of historic buildings and their sites, including shade trees, porches, and operable windows, transoms, shutters and blinds. .2 Increase the thermal efficiency of historic buildings by observing traditional practices, such as weather-stripping and caulking, and by introducing appropriate energy- efficient features, such as storm windows and doors. See Guidelines 3.7.23 and 3.8.9 for additional direction. .3 Replace deteriorated or missing wooden blinds and shutters with matching new units sized to fit the opening. See Guideline 3.7.21 for additional direction. .4 It is not appropriate to install solar collectors in locations 69 GENERAL DESIGN GUIDELINES that compromise prominent roofs. The installation of solar collectors may be appropriate provided it does not detract from the historic character of the property, landmark or historic district. 8.3 Mechanical and Utility Facilities GUIDELINES .1 If a new mechanical system is needed, install it so that it causes the least amount of alteration to the building's exterior façades, materials, and site features. .2 Locate new mechanical equipment and utilities, including heating and air conditioning units, in the most inconspicuous area, usually along a building's rear facade. Screen them from view. .3 Where possible, locate portable window air-conditioning units on rear facades or inconspicuous side facades. Consider noise impacts to neighbors when selecting sites. .4 It is not appropriate to install ventilators, antennas, skylights, satellite dishes or other mechanical equipment in locations that compromise character-defining roofs, or on roof slopes that are prominently visible from the street. .5 Minimize the visual impacts of trash storage and service areas by screening them from the street. 8.4 Signs A sign typically serves two functions: to attract attention and to convey information. Signs designed for a historic building should not detract from important design features of the building. All new signs should be developed with the overall context of the building and district in mind. GUIDELINES .1 Retain and preserve existing historic signs that contribute to the overall historic character of the building or the district. .2 New signs should be compatible in material, size, color, scale, and character with the building. .3 Signs should be subordinate to the overall building 70 MISCELLANEOUS composition and in scale with the façade. .4 Locate a sign on a building so that it emphasizes design elements of the façade itself. In no case should a sign obscure or damage architectural details or features. .5 Simple letter styles and graphic designs are most appropriate. .6 A hanging entryway sign may be located on a porch, or directly above the steps leading to the primary entrance of a structure. 71 GENERAL DESIGN GUIDELINES 8.5 Lighting Traditionally, site lighting was very limited in residential districts. While today there is typically a need for more lighting and higher levels of illumination, both building lighting and site lighting should respect the quality of lighting that characterizes historic residential districts. When selecting specific fixtures and locations, it is also important to consider the impact of site lighting on adjacent properties. GUIDELINES .1 Retain and preserve exterior lighting fixtures that contribute to the overall historic character of a building, site or district. .2 It is inappropriate to introduce or eliminate exterior lighting fixtures if doing so will detract from the overall historic character of the building, site, or streetscape. .3 Lighting should be functional ― not just decorative. .4 Lighting in alleys should be low wattage and focused downward. .5 It is inappropriate to illuminate the facades of houses in residential districts. 8.6 Artwork Artwork includes, without limitations, paintings and sculptures, whether attached to a building or freestanding. GUIDELINES .1 Retain and preserve artwork that contributes to the overall historic character of a building, site or district. .2 Artwork should be subordinate to the overall building. .3 Artwork should not obscure or damage building elements or details. For instance, a mural should not cover windows. .4 Artwork should not permanently alter the building or site, such as paint on unpainted masonry. .5 Artwork should not detract from the historic character of 72 MISCELLANEOUS the building, site or district, nor should it confuse the public regarding the period of significance of the building or district through anachronistic images or details. 8.7 Public Improvements Public improvement features such as street lighting, street and alley paving, tree planting, parks, and sidewalks all contribute to the historic character of a historic district or site. Any public improvement undertaken by the City of Boulder shall be reviewed by the Design Review Committee of the Landmarks Preservation Advisory Board. See Sections 2.3 Alleys and 2.5 Sidewalks for additional direction. GUIDELINES .1 Any public improvement should maintain and reinforce the character of the historic district. 8.8 Americans with Disabilities Act Places of public accommodation are required to provide access to their services and programs under provisions of the Americans with Disabilities Act. In the case of historic buildings, some provision for using alternative measures exists if the property is historically or architecturally significant enough to merit such treatment. When changes to a building or site are necessary, careful consideration must be given to how the changes can be incorporated without compromising the integrity of the historic building, its character- defining features, or its site. GUIDELINES .1 Provide barrier-free access that promotes independence for the disabled to the highest degree practicable, while preserving significant historic features. .2 The appearance of accessibility ramps or elevators should not significantly detract from the historic character of the structure. .3 If the addition of accessibility improvements negatively impacts significant historic elements, these improvements should be designed to be reversible. 73 DEFINITIONS 74 GENERAL DESIGN GUIDELINES 9. DEFINITIONS Alignment The arrangement of objects along a straight line. Balcony A railed projecting platform found above ground level on a building. Arch A structure built to support the weight above an opening. A true arch is curved. It consists of wedge-shaped stones or bricks called voussoirs (vu-swar'), put together to make a curved bridge which spans the opening. Baluster A short, upright column or urn-shaped support of a railing. Balustrade A row of balusters and the railing connecting them. Used as a stair rail and also above the cornice on the outside of a building. Bargeboard A projecting board, often decorated, that acts as trim to cover the ends of the structure where a pitched roof overhangs a gable. Bracket A supporting member for a projecting element or shelf, sometimes in the shape of an inverted L and sometimes as a solid piece or a triangular truss. Cantilever A projecting beam, girder or other structural member supported only at one end; used to support a balcony, cornice, extended eaves or any other extension to a building or structure. Column A slender upright structure, generally consisting of a cylindrical shaft, base, capital, and pillar: It is usually a supporting or ornamental member in a building. Contributing Buildings Those buildings built during the district's period of significance that exist in comparatively original condition, or that have been appropriately restored, and clearly contribute to the historic significance of the district. Such buildings may have compatible additions. 75 GLOSSARY OF TERMS Contributing–Restorable Buildings Those buildings built during the district's period of significance that have original material that has been covered, or buildings that have experienced some alteration, but that still convey some sense of history. These buildings would more strongly contribute, however, if they were restored. Such buildings may have less compatible additions. Cornice A projection at the top of a wall or the top course or molding of a wall when it serves as a crowning member. Deck An uncovered platform, usually with wood decking and railings, that extends from out from the main face of a building. Dormer A window set upright in a sloping roof. The term is also used to refer to the roofed projection in which this window is set. Eave The underside of a sloping roof projecting beyond the wall of a building. Elevation A mechanically accurate, "head-on" drawing of a face of a building or object, without any allowance for the effect of the laws of perspective. Any measurement on an elevation is in a fixed proportion, or scale, to the corresponding measurement of the real building. Facade The front or principal face of a building, or any side of a building that faces a street or other open space. Gable Building ends above eave level of a pitched or gambrel roof. In the case of a pitched roof this takes the form of an angle. The term is also used sometimes to refer to the whole end wall. Historic Context An organizing structure for interpreting history that groups information about historic properties that share a common theme, common geographical area, and a common time period. 76 GENERAL DESIGN GUIDELINES The development of historic contexts is a foundation for decisions about the planning, identification, evaluation, registration, and treat- ment of historic properties, based upon comparative historic significance. Historic Integrity The degree to which a building has retained its original elements. Historically Important Window or Door The feature has retained integrity from the period of significance and is an integral part of the historic design or is essential to the understanding of the architectural type or style. Human Scale Human scale refers to the relationship between the dimensions of a building, street, streetscape or outdoor space to the average dimensions of a human body. Individually Significant Buildings Those buildings that are considered individually eligible for the National Register of Historic Places or for local landmark designation. These buildings have a special character and historical, architectural, or aesthetic interest or value in Boulder’s local history. Interior Energy Panel Interior energy panels are single pane glass panels affixed to the interior of historic windows in order to reduce conductive heat loss and prevent the infiltration of cold air from outdoors. They are an option for increasing energy efficiency without full window replacement. Landmarks Board The City of Boulder's Landmarks Board consists of five volunteer city residents appointed by the City Council to consider applications and make recommendations to Council for landmark and historic district designations and to review proposed exterior alterations to Landmarks or within landmark districts. 77 GLOSSARY OF TERMS Landmarks Board Design Review Committee A Committee that consists of two members of the Landmarks Board and one member of the Planning Department staff and meets weekly to review alteration certificate applications. Molding A decorative band or strip of material with a constant profile or section designed to cast interesting shadows. Generally used in cornices and trim around window and door openings. Mullion A large vertical member separating two casements; the vertical bar between coupled windows or multiple windows; the central vertical member of a double-door opening. Muntin One of the thin strips of wood used for holding panes of glass within a window; also called munnion, bar, sash bar, munton bar. Also, the central vertical member of a door. Non-Contributing Buildings: Those buildings built during the district's period of significance that have been altered to such an extent that original historic elements are not interpretable, and restoration is not possible, also buildings erected outside the period of significance that are not individually significant. Non-Historic Window or Door: Windows or doors that have been replaced, or are so extensively altered that they are inconsistent with the pattern, proportion or materiality of the historic window or door. Non-Historic windows and doors may be retrofitted or replaced. However, the character of the retrofit or replacement should be compatible with the historic character of the building. (See Section 3.7.15). Parapet A low wall or protective railing; often used around a balcony or balconet, or along the edge of a roof. Period of Significance The time period during which the majority of 78 GENERAL DESIGN GUIDELINES contributing buildings in a historic district were constructed. The period of significance is generally established by the designating ordinance for a district. Pitch The slope of a building element, typically expressed as the ratio of vertical rise per horizontal run, e.g,. a 3/12 pitch indicates a rise of 3” for every 12” of horizontal run. Plate Height The distance between the foundation or the topmost horizontal piece of framing at the top of a wall and where the next floor framing begins or where the roof form starts. Post A piece of wood, metal, etc., usually long and square or cylindrical, set upright to support a building, sign, gate, etc.; pillar; pole. Primary Elevation The front or principal elevation(s) of a building that face a public right of way or other important public space such as a park. Typically, the façade of a building is the most prominent elevation and will contain character defining doors and/or windows. Protection The act or process of applying measures designed to affect the physical condition of a property be defending or guarding it from deterioration, loss or attack or to cover or shield the property from danger of injury. In, the case of buildings and structures, such treatment is generally of a temporary nature and anticipates future historic preservation treatment; in the case of archaeological sites, the protective measure may be temporary or permanent. Retrofit In a rehabilitation project, the installation of new materials into an existing fabric. For example, a retrofitted window would be the installation of new glass (i.e. low e glass) that is fitted into an existing window sash. Roof The top covering of a building. Some types: Gable roof has a pitched roof with ridge and vertical ends. 79 GLOSSARY OF TERMS Gambrel roof is a variation of a gable roof, each side of which has a shallower slope above a steeper one. Hip roof has sloped ends instead of vertical ends. Shed roof (lean-to) has one slope only and is built against a higher wall. Jerkin-head (clipped gable or hipped gable) is similar to gable but with the end clipped. Sash A window component: see window parts. Secondary Elevation Typically a side of a building that has less public visibility, and may have fewer significant character defining features than on the façade. An elevation that has visibility from an alley may be considered a secondary elevation. Siding The narrow horizontal or vertical wood boards that form the outer face of the walls in a traditional wood frame house. Horizontal wood siding is also referred to as clapboards. The term "siding" is also more loosely used to describe any material that can be applied to the outside of a building as a finish. Sill The lowest horizontal member in a frame or opening for a window, door, or framed wall or partition. Simulated Divided Light Window Windows that have muntins affixed to the inside and outside of the panes of glass to simulate the look of a true divided light window. Soffit The underside of a structural part, as of a beam, arch, etc. Tertiary Elevation The side of a building that typically has little or no visibility from the public right of way and is usually located at the rear of the building. True Divided Light Window Windows that use muntins to form multiple individual panes of glass in the sash. 80 GENERAL DESIGN GUIDELINES Vernacular Buildings in indigenous styles constructed from locally available materials following traditional building practice and patterns and not architect-designed. Very Historically Important Window or Door A window or door that has retained substantial integrity from the period of significance and is characterized by at least one of the following: 1. Defines the architectural type or style of the building and without it the architectural significance would be eroded. 2. Is constructed of a rare or unusual material that would be difficult or costly to replicate (i.e. stained or leaded glass). 3. Was executed with a high degree of craftsmanship that would render its restoration difficult or costly. 4. Conveys artistic merit through skillful integration of design, material, and color which is of excellent visual quality. 5. Demonstrates superior craftsmanship or is an example of the uncommon through elements of architectural design, details, or craftsmanship that are representative of a significant innovation. Visual Continuity A sense of unity or belonging together exhibited by elements of the built environment because of similarities among them. Window Condition Class I: Small repairs, which are usually performed as part of a building’s annual maintenance program. This may include paint removal, re-glazing, weather- stripping, caulking, and repainting Class II: Shows a small degree of physical deterioration but can be repaired in place by patching, waterproofing, consolidating, or re-gluing existing material. Class III: Localized deterioration in specific areas that can be removed and replaced without requiring a full feature replacement. 81 GLOSSARY OF TERMS Class IV: Damage beyond repair, including a completely rotted window sill, warping or a combination of Class III repairs. Window and Door Replacement Application and Survey An application & survey which must be submitted as part of a Landmark Alteration Certificate for the replacement or retrofit of a window or door on a historically designated building. The application and survey outline the methodology used to identify the condition, location and historic significance of the window or door and is used to determine if replacement, retrofit or repair is appropriate. Window Parts The moving units of a window are known as Sashes and move within the fixed Frame. The Sash may consist of one large Pane of glass or may be subdivided into smaller panes by thin members called Muntins or Glazing Bars. Sometimes in nineteenth-century houses windows were arranged side-by-side and divided by heavy vertical wood members called Mullions. Head Jamb Rail Brickmoul d Stiles Blind Stop Interior Stop Side Jamb Muntin s Sill Apron Stool Interio r Casing Upper Sash Parting Stop Check Rail Lower Sash 82 CITY OF BOULDER LANDMARKS BOARD bouldercolorado.gov/government/board-commission/landmarks-board 83