GUIDELINES FOR REHABILITATION OF TRADITIONAL COMMERCIAL BUILDINGS DESIGN GUIDELINES

Transcription

1 GUIDELINES FOR REHABILITATION OF TRADITIONAL COMMERCIAL BUILDINGS DESIGN GUIDELINES PAGE 13

2 DESIGN GUIDELINES The following design guidelines have been developed to guide appropriate design in the Downtown Topeka BID and the North Kansas Avenue corridor. The Context of the Street standards are applicable to both areas in general and the Building Facade standards are applicable to all traditional commercial buildings. The Building Facade Building Composition - Traditional Elements - Building facades should relate to the surrounding buildings. Existing traditional commercial buildings should retain traditional elements and proportions, as shown on Illustration 14. Storefront Recessed Entry The entrance can be recessed to allow for protection from the elements and protection of sidewalk pedestrians from outswinging doors due to egress. Bulkhead A bulkhead is a member of an entrance frame which forms a base for a sidelight adjacent to a door. Cast Iron Column A column, in this case, cast iron, is a structural compression member which supports the load of the upper façade. The column, if decorative, can be exposed for aesthetic reasons. Display Window The display window is an assembly consisting of glazing and framing. It can be designed to allow for street and sidewalk viewing of displays. Masonry Pier The masonry pier is an arrangement of stone, brick, etc. to form a structural compression element, similar to a cast iron column, that supports the load of the upper façade. Transom Window A transom window is panes of glass above the display window and entry separated by a horizontal bar of wood allowing for additional natural light. The panes of glass can be operational to allow for ventilation. Lower Cornice The lower cornice is an ornamental trim element to finish or crown the storefront. Upper Facade Window Sill The window sill is the horizontal bottom member of a window frame. The sill can be made of brick, stone, wood, etc. Upper Window The upper window is a glazed opening in the upper façade to admit light and air. Window Lintel The window lintel is a horizontal structure member, such as a beam made of steel, stone or wood, over the window which carries the weight of the wall above. Ornamental Masonry Pattern An arrangement of brick, stone, etc. to create a decorative pattern in the upper façade. Cornice or Cap Cornice The cornice is the ornamental trim element at the meeting of the roof and wall usually consisting of bed molding, soffit, fascia, and crown molding. Cap The topmost member of a vertical architectural element, such as a façade, projecting with a drip as protection from the weather. Illustration 14 The traditional commercial building façade has several features illustrated here. PAGE 14

3 Cornice/Building Cap - The cornice defines the top of the building and emphasizes the relationship of the top of the building to adjacent buildings. A number of buildings have an applied pressed metal cornice. More common on the brick buildings in Downtown Topeka and in the North Kansas Avenue corridor are decorative brick corbelling defining the top of the building facades with a tile or stone cap on the top of the brick parapet wall (the portion of the facade that projects above the roof). The parapet wall is a frequent source of water infiltration due to improper or failed flashing at the cap on the masonry wall or at the wall/roof juncture. As a result of water infiltration, it is common to find deteriorated or missing mortar and surface spalling of masonry units at the top of the building facade. Existing cornices and/or building caps should be retained where possible and repaired as needed. When applied cornices have been removed, encourage replacement of the historic cornice if feasible. If replacement is not feasible, design a simplified cornice to define the top of the building and maintain the visual unity of building tops along the block. Illustration 15 Current building condition on left. On the right is a proposed cornice/building cap to replace missing/removed historic fabric. PAGE 15

4 Upper Façade - Improvements to the upper façade should follow the recommended guidelines for rhythm, regulating lines, materials, and color outlined under Context of the Street (Pages 23-25). Upper windows are a predominant character-defining feature on multistory buildings. The original masonry window openings should always be maintained. Under no circumstances should window openings be blocked in or covered with a solid material. Such coverings present a fire hazard because solid coverings can obscure flames and serve as an impediment to fire fighting. Windows that have been downsized or covered should be reopened to maintain the size and proportion of the historic window openings. Window coverings such as shades or curtains can mask unused upper floor space and are an acceptable alternative to blocking in windows that are no longer needed for daylighting or ventilation. When upper level windows are missing or are in need of replacement, the openings should not be downsized to accept stock sizes; replacement windows should fill the entire opening and resemble the style and profile of the original window. Windows should always use clear glass. Reflective or tinted glass is not recommended. There are a variety of glass products that minimize heat gain and loss without substantially affecting appearance. Examples of such products include thermal glazing with clear or Low "E" glass. Illustration 16 Current upper façade (top). Proposed upper façade window replacement (below). PAGE 16

5 The Storefront - Storefronts were historically composed almost entirely of glass which created visual openness. This openness creates an inviting relationship to the street and emphasized the pedestrian orientation of the commercial district. Extensive storefront windows should be retained. Where storefronts have been filled in, rehabilitation should restore the visual openness of the storefront. The storefront should always fit within its original opening. Storefront revisions should retain the original elements: transom window, display windows, bulkhead, and entrance (door). The storefront should use appropriate materials as outlined under Context of the Street (Pages 23-25). The size, proportions and alignment of windows, door, and bulkhead should relate to neighboring buildings. Display windows should retain the size and proportion of the original openings. Display windows that have been downsized or covered should be restored to their original size and proportions. Display windows should be clear glass. There are a variety of glass products that minimize heat gain without substantially affecting appearance. Retain the original size and proportions of the transom window opening. If transom windows have been covered or the glass removed, transom windows should be restored to their original appearance. When restoration of the transom window glass is not feasible, the size and proportion of the original opening should be maintained. When ceiling heights have been lowered so that the transom windows are above the new ceiling, opaque panels (wood or glass) can be framed-in to resemble the form and profile of a historic transom window. The transom window area can also be covered by an awning or used for signage (see awning and sign guidelines). The original building entrance(s) should be retained when possible. Doors in the storefront should use clear glass. Avoid using solid metal or solid wood doors in a glass storefront. Illustration 17 Current storefront on left. Proposed storefront with canopy and transom windows on right. PAGE 17

6 Business Signs - Signs are a significant part of the building's appearance and therefore, should be well designed and placed in an appropriate location on the building. Signage should be in one or more of the traditional locations and should consider the following guidelines. Signs should generally be oriented to pedestrians and/or slowmoving automobiles. Business signs should typically not be located on the upper facade. Traditional locations for signs on historic commercial buildings include: on a canvas awning, on the window glass or glass door, mounted flush to the building facade in the panel above the awning or transom windows, on the transom window area, or a small projecting sign oriented to pedestrians. Signs should be kept subordinate to the building and fit within the existing features of the facade. Signs should not cover up architectural details on the building. Window signs should not obscure the display area. Generally, wood, metal and glass are the best base material for painted signs. Illustration 18 Signs can be located on many different surfaces, but sign design and placement always should be carefully considered to attract attention, but not contribute to visual clutter or chaos. As a general rule, back lit signs are not appropriate for historic commercial buildings. If lighting is desirable, spot lights mounted on the building surface are generally more appropriate. Sign colors should complement the colors of the building. Signs should be clear, concise and easy to read. PAGE 18

7 Awnings - Awnings protect pedestrians from the weather and protect merchandise displayed in windows from sunlight. Historically, awnings were both fixed and retractable. Awnings may be appropriate depending on the building's location and exposure to sunlight. Awnings that detract from the historic character of the building should be removed. The awning size and shape should fit the original masonry opening. Awnings should not obscure the architectural features of the building. Typically fabric, canvas, or vinyl are the most appropriate awning materials; wood, aluminum, shingles, plastic or shiny/slick finishes on fabric/canvas/vinyl are generally not appropriate. Fixed or retractable awnings can both be appropriate. Historic retractable awning hardware should be retained and reused when possible. Fixed awning frames should incorporate the body of the awning only; the valance of the awnings should not be fixed or rigid. As a general rule, back lit awnings are not appropriate for historic commercial buildings. If lighting is desirable, spot lights mounted on the building surface are generally more appropriate. Awnings are an appropriate location for business signs. Illustration 20 This figure illustrates an inappropriate new awning. The proposed awning spans from building edge to building edge exceeding the size of the original window opening. Additionally, the proposed awning does not have a valance, the entire awning is rigid/fixed. Illustration 19 This figure illustrates a typical historic fabric awning with retractable hardware. Existing historic awnings and awning hardware should be retained when possible. Illustration 21 This figure illustrates more appropriate new awnings. The proposed awning fits the original window opening. The lower awning meets general guidelines including: a degree angle, a 6-8 inch loose valance, and the lower edge of the awning is 7-8 feet from the ground. The upper awnings have a 45 degree angle, fit the opening width and extend to the half way point of the opening height. PAGE 19

8 Materials - Building materials are an important consideration in how well buildings relate to each other and their surroundings. Materials can be indicative of architectural styles and through their inherent colors often establish the basic color scheme of a building facade. The traditional commercial buildings in Downtown Topeka and the North Kansas Avenue corridor are predominately brick with brick or stone ornamentation. In addition there are a significant number of buildings with stone, glazed brick, and terra cotta facades or façade components. There are a few pressed metal upper facades and many masonry facades with pressed metal or cast iron components/ornamentation. Most buildings have a decorative corbelled brick parapet. A few buildings have an applied pressed metal cornice or a terra cotta cornice. The majority of brick buildings have brick or limestone window lintels and sills, although some have ornamental metal window sills and caps. All existing historic building materials should be retained. Proposed building improvements should generally use traditional materials documented to the historic building or materials similar to the historic materials that are used on buildings of similar design and construction. Contemporary materials may be appropriate if the design and composition relate to the context and other design standards are met. Metal or wood siding/panels, wood or asphalt shingles and dark or mirrored glass are generally not appropriate. Upper floor windows in multi-story buildings were typically double hung windows with wood frames. Many of the original windows are intact, however many have been covered over or filled in and others have been replaced with a variety of windows with either double hung sash and single, fixed sashes. Most storefronts were originally wood and/or bronze storefront windows and doors enframed by stone or brick piers. Only a few original storefronts remain. Several storefronts retain their cast iron columns. Many buildings have a steel I-beam spanning the storefront bay, which both supports the masonry wall above and serves as the storefront cornice. Alterations to the existing storefronts over the years, including those that are old enough to be considered historic, have included the installation of metal and glass panels, brick and stone veneers, and wood siding. These alterations typically changed the proportions and regulating lines of the original storefront. The original bulkheads or bases of the storefronts were typically masonry or wood; however, alterations with new brick, tile, metal panels, and wood are common. PAGE 20

9 Illustration 22 Ceramic mosaic tile at vestibule floor. Illustration 27 Historic wood doors: note scale and proportions. Illustration 25 Historic decorative terra cotta window surrounds. Illustration 26 Traditional stone column and cap. Illustration 23 Historic terra cotta cornice and keystone element. Illustration 24 Historic sandstone cornice. Illustration 28 Traditional steel lintel with rosette fasteners. Illustration 29 Traditional patterned terrazzo at vestibule floor. Illustration 30 Traditional cast iron column and cap. PAGE 21

10 Color - Color plays an important role in how well a building fits into its environment and should be considered when rehabilitating existing buildings. A good source for paint colors typical of, and appropriate for historic commercial buildings are the "heritage" or "historic" paint colors offered by many paint manufacturers. Although personal preference is a major factor in the selection of paint color, the following guidelines should be considered when selecting colors. Coordinate color selections with the original colors of the building, the natural color existing in the present building materials (brick, limestone, etc.), and colors used on adjacent buildings and throughout the district. The dominant colors within the commercial districts tend to be the muted brick reds and stone tans of existing masonry. Accent colors chosen for color schemes should complement the natural colors that already exist in the building and its immediate surroundings. A paint scheme for typical historic commercial buildings should typically consist of no more than three colors - one major color for the body and two accent colors for the primary and secondary trim. The color of the predominant building material (typically brick or stone masonry) should be considered the major body color. If the historic building material has been modified or painted, a natural color similar to the natural color of the historic material should be used for the body. Modest or muted color schemes are typically more appropriate and effective than schemes that use bright, eye-catching colors. As a general rule in determining whether or not to paint a building or building features, it is best to paint materials that have been previously painted and it is best not to paint masonry that is not painted. It may be necessary to repaint masonry that has been previously painted because it is not feasible to remove existing paint from the masonry surfaces - see Paint in Building Maintenance section (Page 31). If paint removal is not feasible and the body of a masonry building must be repainted, the paint color selected should be similar to the natural color of the masonry substrate. Likewise, when previously painted brick or stone trim, such as window lintels or sills must be repainted, they should be painted a color to match the natural color of the material. Accent colors should be used primarily on wood trim such as window frames, storefront frames, and bulkheads, not on masonry details. Historically, cast iron and pressed metal components were often painted to resemble stone. When stone and brick sills and lintels were painted, they too were painted the color of stone. Contemporary tastes seem to prefer to paint cast iron and pressed metal components with accent colors to draw attention to their ornamentation. Introducing an accent paint color on decorative brick, limestone, or pressed metal details, causes the details to be accented which makes the buildings appear less homogenous than the original design intent. Illustration 31 This storefront color scheme uses a taupe and off white combination accented by a low intensity red on the doors and awnings. Illustration 32 The brick façade of this commercial building is accented with painted ornament in two tones of gray. PAGE 22