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American Planning.Sssucixriun L•+
<br />cities, warehouse and industrial areas have
<br />morplled into 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 activity patterns have been transformed.
<br />Under die current, use-based zoning rystem,
<br />such a change would be considered drastic. The
<br />land-use category has gone from industrial, atone
<br />end of the spectrum, to residential, at the other,
<br />although ro the average onlooker, the place looks
<br />pretty much the same. In this example, aform-
<br />based code would regulate the part Ch;iL 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 the code.
<br />In some cities, planners have found ways to
<br />bend land-use zoning ro enable this kind of
<br />reuse to pron7ote the revitalization of older
<br />neighborhoods, particularly those with good
<br />architectural "bones." B cat such modifications
<br />are typically made on a case-by-case basis or
<br />within narrowly defined special districts.
<br />Meanwhile, in new growth areas and in
<br />most existing neighborhoods, use-based zon-
<br />ing remains rile law of the land. One result is
<br />the suburbanization of city 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:~•I(iol~ if~»~ n iu 7+uri:
<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 charerte, lasting
<br />several days. The community's "consensus
<br />vision" is CUI7Veyed C11rUUgl7 3 range of VISLIalS,
<br />nlcllldlll`r perspective draWIl7gS, site anllySls
<br />diagrams, and an illustrative plan. That plan,
<br />which resembles an aerial photo, includes
<br />proposed buildings (shown as rooftops), Ivey
<br />natural features, and e-eisring and planned
<br />public spaces.
<br />The first step in coding is to translate the
<br />illustrative plan into 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 />latingplan assigns a building type or types to
<br />each available parcel of Land. Other kinds of
<br />regulating plans indicate a range of building
<br />or Frontage types that may be constructed in a
<br />certain area.
<br />Clean}', when it comes to detailing the
<br />urban environment, one size does not fit a11,
<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. Yet a shopfront in the same
<br />neighborhood may be more accessible to cus-
<br />tomers if it is set at grade.
<br />Although public buildings areverv important
<br />to New Urbanist designers, they are typically
<br />not coded. Such buildings are usually indicated
<br />in d1e regulating plan by a conceptual footprint
<br />chat serves as a placellolder until all actual design
<br />is formulated (often years in the future).
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<br />The physical characteristics of each building
<br />type are summarized in the building stan-
<br />dards-axes of :uu7orated building cross-sec-
<br />tionsand plan diagrams assembled on a single,
<br />letter-size sheet. In some cases, all the build-
<br />ing ~~pes are combined into a matrix and
<br />formatted as a poster.
<br />Regardless of layout, building standards ,
<br />typically establish these parameters: '
<br />Building height is a key stuld:rrd. A maxi-
<br />mum number of floors (or dimension-ro-die-
<br />eave) is set to ensure that a building does no
<br />overwhelm its neighbors. Unlike use-based
<br />zoning, form-based codes also specify a mini-
<br />mum height in order to maintain a proper
<br />street wall.
<br />Siting standards control the placement of
<br />structures in relation to fronting streets and
<br />adjacent building lots. Dimensions to Front,
<br />side, and rear building lines, as well as the
<br />location and configuration of entl•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 pal-t of the building envelope
<br />standards, but the approach here is quite dif-
<br />ferent from 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 tlZe cross-section diagram.
<br />This approach makes lC eaSV t0 as51gR dif-
<br />ferent uses to each floor of amixed-use devel-
<br />opment, and avoids the problem of trying to
<br />communicare the same information on a flat
<br />map. (The plethora of colors, stripes, and cross-
<br />hatch patterns on most zoning maps shows
<br />how confusing this can be.)
<br />Thoroughfare stal7dal-ds for a range of recom-
<br />mendedstreet rypesmay also be part of the code
<br />in places where streets are not individually de-
<br />signed. Such standards are indicated by section
<br />diagrams with dimensions For travel and park-
<br />ing lanes, sidewalks, medians, al7d pI•anring 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 tel•ms Char 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. Howevel•, some communi-
<br />ties-master-planned developments, special
<br />retail districts, historic districts, among others-
<br />may want to exercise a higher level of control
<br />over d1e appearance of individu:ll 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. Style
<br />may also be included as p;lrt of Che afChlLeC-
<br />tural standards, but not in every case. M;u7v
<br />New Urbanists CI1UUSe to avoid direct refer-
<br />
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