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American Pl:uvting .4tiwtia[iun 17
<br />cities, warehouse and industrial areas have
<br />morphed inro trendy arts districts with galler-
<br />ies and restaurants at street level and loft
<br />housing above. The form of the buildings has
<br />remained fairly constant, while internal uses
<br />and activirv patterns have been transformed.
<br />Under the current, use-based zoning system,
<br />such a clr;tnge would be considered drastic. The
<br />land-use crtegory• has gone from industrial, at one
<br />end of the spectrum, ro residential, at the ocher,
<br />although to dle average onlooker, the place looks
<br />pretty much the same. In this example, aform-
<br />based code would regulate the part chat had
<br />remained the same-the form of the building
<br />and the configuration of the street and sidewalk.
<br />Use would be regulated, too, but at a secondary,
<br />rather than primary level of dle code.
<br />In some cities, planners hayr found ways to
<br />bend land-use zoning ro enable this kind of
<br />reuse to promote the revitalization of older
<br />neighborhoods, particularly those with good
<br />architectural "bones." But such modifications
<br />are typically glade ocl a case-by-case basis or
<br />within natrrowly defined special districts.
<br />Meanwhile, in new growth areas and in
<br />most existing neighborhoods, use-based zon-
<br />ing remains the law of the land. One result is
<br />the suburbanization ofciry neighborhoods by
<br />provisio ns such as setback rules that force houses
<br />far back on their lots and away from each other.
<br />l;~~iiin~ ~f~~~\ n iu ~~ ~~rk
<br />Generally, the creation of a form-based code
<br />is interwoven with a community visioning
<br />process. The process typically includes a
<br />public design worlshop, or charette, lasting
<br />several days. The community~s "consensus
<br />~ision° is conveyed dlrough a range ofvisuals,
<br />includin« perspective drawings, site analysis
<br />diagrams, and an illusuative plan. That plan,
<br />which resembles all 3erl'aI photo, includes
<br />proposed buildings (shown as rooftops), key
<br />natural features, and exlSLlllg and planned
<br />public spaces.
<br />The First step in coding is co translate tiie
<br />illustrative plan inro a more diagrammatic regu-
<br />lating plan, which indicates what goes where.
<br />This document, while similar in some ways to a
<br />zoning map, is Far more detailed. It also omits
<br />any direct labeling of uses, a job that is handled
<br />in the building standards described below.
<br />In one kind of form-based code, the regu-
<br />lating plan assigns a building Type or types to
<br />each available parcel of land. Ocher kinds of
<br />regulating plans indicate a range of building
<br />or frontage types that may br constructed in a
<br />certain area.
<br />Clearly-, when it comes to detailing the
<br />urban environment, one size does not fit all,
<br />
<br />and the new approach to coding recognizes
<br />that. Coding by building type provides the
<br />freedom to create one set of rules for one
<br />building, type and another set for a different
<br />type. For example, a townhouse may Function
<br />best with its main floor lifted ahalf-level
<br />above grade for interior privacy, with a Front
<br />stoop for access. Y'et a shopfront in the same
<br />neighborhood may be more accessible to cus-
<br />tomers if it is set at grade.
<br />Althoughpublic buildings areverv important
<br />to New Urbanist designers, they are n'picauy
<br />not coded. Such buildings are usually indicated
<br />in die regulating plan by a conceptual Footprint
<br />that serves as a placellolder until an actual design
<br />is formulated (often years in the future).
<br />I\'ui~ tdti(I lba~lt~
<br />The physical characteristics of each building
<br />rvpe are summarized in the building sLail-
<br />dards-a set of annotated building cross-sec-
<br />tions and plan diagrams assembled on a single,
<br />letter-size sheet. In some cases, all the build-
<br />ing types are combined inro a matrix and
<br />fonnacted as a poster.
<br />Regardless of layout, building standards
<br />typically establish these parameters:
<br />Building height is a key standard. A maai-
<br />mumnumber of floors (or dimension-to-the-
<br />cave) is set to ensure that a building does nut
<br />overwhelm its neighbors. Unlike use-based
<br />zoning, Form-based codes also spccif~~ a mini-
<br />mum height in order to maintain a proper
<br />street wall.
<br />Siting standards conu•ol the placement of
<br />structures in relation co fronting streets and
<br />adjacent building lots. Dimensions to front,
<br />side, and rear building lines, ;u well as the
<br />location and configuration ofenu-ances, park-
<br />ing, yards, and courtyards are specified. Key
<br />building elements-i.e., windows, doors, and
<br />porches-are :also controlled by the standards.
<br />Uses are also part of the building envelope
<br />standards, but the approach here is quite dif-
<br />ferentFrom conventional zoning. Permissible
<br />uses, stated in general terms (e.g., retail, resi-
<br />dential), are identified For each building type
<br />and labeled on the cross-section diagram.
<br />This approach makes it easy to assion dif-
<br />ferent uses to eaich fluor of amixed-use~devel-
<br />opment, and avoids the problem of trying to
<br />communicate the same information on a flat
<br />map. (The plethora of colors, stripes, and cross-
<br />hatch patterns on most zoning reaps shows
<br />how confusing this can be.)
<br />Thoroughfare standards for a range of recom-
<br />mended street types mar• also be pan of the code
<br />in places where streets are not individually de-
<br />signed. Sue;h standards are indicated by section
<br />diagrams with dimensions For travel and park-
<br />inglanes, sidewalks, medians, and planting strips.
<br />Tree alignment and property lines are also shown.
<br />Finally, many codes include a set of land-
<br />scape standards listing appropriate tree and
<br />groundcover species. Most codes also provide
<br />a glossary that defines terms that are used in a
<br />specific way in the document.
<br />These components constitute the basics of
<br />a form-based code. They control the urban
<br />design elements that New Urbanists are most
<br />concerned with. However, some communi-
<br />ties-master-planned developments, special
<br />retail districts, historic districts, anion; others-
<br />may want to exercise a higher level of control
<br />over the appearance of individual buildings.
<br />For this reason, some form-based codes in-
<br />clude architectural standards.
<br />This optional "dress code" controls exte-
<br />rior colors, materials, and construction tech-
<br />niques. Particular emphasis is given to clad-
<br />ding, doors, windows, stairs, and roofs. SR~Ie
<br />may also be included as part of the architec-
<br />tural standards, but not in every case. Ivi:ulv
<br />New Urbanists choose to :rwoid direct refer--
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