Agenda - Planning Commission - 05/04/2017

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resource for this work is A Field Guide to American Houses, first published by Alfred A. Knopf in 1984 and revised in 2o13. This book has numerous drawings, photos, and descrip- tions of the styles that can be used as the basis for the code language and in evaluation of existing buildings. It is important in doing this to specifically identify style or styles in the district. This makes it easy to review any proposed exterior change to determine if the changes are consistent. Design Guidelines Design standards and guidelines are intended to preserve the existing historic character and prevent any exterior activities that would de- stroy or be inconsistent with that style. The de- sign rules for exterior modifications to historic properties should derive from the documenta- tion of the historic styles in the district. They should address style, colors, materials, and landscape elements that create the district's character, while avoiding overtly subjective elements. The task of developing design stan- dards and guidelines for new construction and non -historic buildings is more difficult. Most current development has an archi- tectural style that is neo-eclectic. The homes are modern interpretations of past styles like colonial, Tudor, or Victorian; while they have some historic style elements, they will never be (ike the historic structures. For new construction, what is needed is a detailed list of the elements that must be incorporated to conform to the desired historic character. The design rules should contain a list of manda- tory elements and a group of optional ele- ments, from which a certain number must be chosen. The jurisdiction should consult with local home builders to ensure the guidelines produce a compatible building that will be marketable in the neighborhood. With builder support it is easier to include vacant lots in a district. Meanwhile, the development of design guidelines for existing non -historic buildings requires a very careful analysis of each such building in the district for style, materials, color, use, type of construction, massing, and existing condition. Condition is important because it provides information about the likelihood that a building will need permits that require the historic board's approval. An assessment of each such building should be developed using the same style and de- sign elements used in the historic analysis. Formulate a design strategy for each type of non -historic building that might seek to add a room or do minor exterior work. The design guidelines should provide clear policy to apply in approving applications for major repair or additions on these build- ings. It a mistake to require them to choose between disinvestment and meeting impos- sibly expensive conversion costs. The experi- ence with nonconforming uses is a caution- ary lesson. Planners originally thought that nonconforming buildings would be torn down. History shows they rarely disappear, and they generally suffer from disinvestment that low- ers all property values in the neighborhood. In drafting standards, a list of enhancements, that have reasonable costs should be devel- oped so landowners have several options. For example, a porch across the entire front is an expensive requirement, but adding some trim to a small existing porch is a more acceptable solution. Avoid requiring major facade and roof changes, as they are very expensive. When style and massing are dramatically different, consider mitigation that'seeks to hide the incompatibility. Two mitigation strat- egies are obvious: color change and landscap- ing. Painting eliminates a sharp color contrast that draws attention to the building's differ- ences. Greenery can hide a multitude of sins because it represents a mass that screens the view ofthe building from the street. Requiring the planting of canopy trees and large ever- greens in the front yard will screen the view of the upper stories of the building. Foundation plantings and understory trees can reduce the ground -level view. The sidebar includes lan- guage that can be used to provide the desired level of mitigation in the design guidelines. Mitigation assumes that non -historic buildings are likely to remain. The idea is to provide actions that allow an owner to make needed exterior repairs or reinvest in the dwelling. it hides the incompatibility rather than eliminating it. These strategies do not in- volve major costs for a land owner. In all cases the effort to address incompatible buildings in the districts should be designed to encourage reinvestment to preserve the economic value of the district. Developing design guidelines for com- mercial areas can be easier as the focus is on street -facing facades. Many historic commer- cial district buildings will be largely compat- ible, with only modest style or height differ- ences. An analysis should look at block faces. If more than 15 percentofa block face is out of the style, the suitability for a historic district is questionable, and the community may want to consider design guidelines without a historic designation. An exception is a building whose facade was "modernized" in the last century. if the business community can be convinced that historic designation and restoring fa- cades will enable the area to generate sub- stantially more revenue, such restoration may be supported. Government grants to assist in the cost makes this more feasible. For new buildings, only the street facade needs review. Height, general window pro- portions, floor to floor heights, colors, and materials are elements that should be the primary focus, as these can be addressed eas- ily in new buildings. The cost of making a new building compatible should not be too great. Some style elements like terra cotta details are very expensive and should be avoided. Commercial uses often use false facades to produce a desired skyline; so this can be a reasonable approach to achieving a matching style. Sample Mitigation Provisions Mitigation. Lots XX, XX, and XX in the historic district have been identified as so different from the styles and character of the district that there is no practical means of making them compatible in style. When any such lot applies for a building permit that involves an increase in the floor area of the building or sub- stantial structural repair, the historic preservation board may approve the application provided the following miti- gation steps are undertaken: .:` One plant unit shall be planted in the front yard for every 1,600 square feet of land area in that front yard. The board shall count existing canopy trees and evergreen trees that are in good health and over 4o feet tall toward the requirements. The shrubs and understory trees shall be in- stalled to maximize the screening of the lower levels of the building. 2. The building shall be painted in ap- proved colors for the district to better match the adjoining buildings. ZONING PRACTICE 4.17 AMERICAN PLANNING ASSOCIATION I page 4