Conceptual Design

P A R T I I I

CONCEPTUAL DESIGNDennis Couture, A.S.L.A., R.L.A.

IntroductionConceptual Design represents the initial effort of describingalternative plans that satisfy the development program ob-jectives in light of the site characteristics identified in thesite analysis. It requires full recognition of the client pro-gram components, initial site assessment, site context, andplanning and regulatory controls.

Sketches, functional diagrams, or concept plans are nor-mally completed to illustrate a framework for the given de-velopment program. They generally represent diagrams ofthe potential distribution of land uses and major circulationrequirements. The effort seeks to meld all pertinent com-prehensive or master planning information with site-specificconsiderations to illustrate how the site might best be de-veloped. For large-scale development, this initial cut at thedesign effort is often accomplished in what are termed‘‘blob’’ or ‘‘bubble’’ diagrams. The intent is focused less onsophisticated graphic technique and more on fostering di-alogue, a preliminary review and assessment, and confir-mation of design direction among the design teamparticipants. Concept plans reflecting land use distributionand associated circulation are reviewed in the context oftheir preliminary implications on infrastructure require-ments as well as economic, functional and political feasi-bility. This phase, similar to the more subjective assessmentincluded in the initial feasibility and site analysis steps,moves from the review of general intent to actual physicaldiagramming of use arrangements. This level of conceptu-alization is generally completed prior to the investment ofresources and time resolving more detailed levels of design.

STEP 3: CONCEPTUAL DESIGNThere are generally multiple solutions for the design of anyone site. It is common for alternative concept plans to be

developed as part of this initial conceptual design phase.The ensuing discussion with the development team mayprompt a dialogue as to the pros and cons of the varioussolutions and identify problems the designer alone may nothave anticipated. The end products associated with the con-cept design phase may be a series of sketches or diagramshighlighting the distribution of land uses and preliminaryinfrastructure requirements. The diagrams themselves maybe annotated to underscore the advantages or disadvantagesassociated with the depicted solution and memorialized forfuture reference.

As demonstrated in Figure III.1, conceptual levelsketches generally include preliminary delineation of suchconsiderations as:

� Points of site access together with an initial align-ment of major vehicular circulation routes. Theprincipal road network should be developed in thecontext of any public comprehensive or master plan-ning policies or recommendations.

� A distribution of major land use elements by type.The delineation should reflect the approximate area re-quirement for each use to begin to gauge the massingor relative area requirements necessary to accommo-date individual program components.

� Delineation of areas mandated or desirable as openspace based the previously completed site analysis,such as floodplain, protection areas, wetlands, maturewoodland, and streams and stream valleys.

� Preliminary determination of the need and locationof major public facilities such as schools, parks, fire

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CONCEPTUAL DESIGN

CONCEPTUAL DESIGN 191

stations, and libraries, as identified in public planningdocuments

While normally not a formal public submission docu-ment, conceptual sketch plans do provide information suit-

able for early discussions with appropriate public officials.They provide sufficient information to obtain an informalassessment by appropriate public agents /officials as to thedevelopment plan’s compliance with public comprehensiveand land use policies and the local political climate.



CONCEPTUAL DESIGN



CONCEPTUAL DESIGN

193

C H A P T E R 1 2

DEVELOPMENT PATTERNSAND PRINCIPLESDennis Couture, A.S.L.A, R.L.A

INTRODUCTIONThis chapter presents an overview of some of the moreprevalent land use types and development patterns thatcomprise our contemporary built environment. It offers ageneral discussion regarding development intensities anddesign patterns, including some of the more widespreadinfluences on development activity. Such influences rangefrom aesthetic and prevalent community attitudes regardingland development project design to the more formative fac-tors associated with environmental, political, and economicconsiderations that guide site design and engineering ac-tivity.

Perhaps the most overriding consideration for any landdevelopment endeavor should be the project at hand in thecontext of the larger community. Community in this senseis more than the physical characteristics of a given project’ssurrounds. It embraces the extant sociocultural, political,and economic paradigms that model the dynamics in anygiven jurisdiction, resulting in the land development typesand patterns that are built. As local context offers a guideto project design opportunities, so do more universal con-structs that have evolved in response to the real and per-ceived shortfalls of contemporary development trends.Sensitivity to the urban-suburban-rural distinction in de-velopment types is simplistic. Development considerationsthat are mindful of the community-making and place-making opportunities and design principles associated withtraditional design, such as traditional neighborhood design(TND), neotraditional, and new urbanism, afford a renewedperspective on both the dynamics of community and theopportunities for meaningful site and project design. Sim-ilarly, constructs associated with the advocacy of smart

growth and green infrastructure offer meaningful insightinto responsible land development activity. These latter con-siderations are appropriate across the spectrum of urban-rural development activities.

An extensive overview of the basic tenets associated withthese more recent ideological approaches to land develop-ment is beyond the purview of this chapter. Contemporaryliterature and professional journals abound with informa-tion on both theory and practical application. Familiaritywith this information is particularly relevant for land designagents given that these approaches are perhaps more inter-twined in the livability and marketing side of land devel-opment and site design than might be evident from in-placeland use regulatory controls, statutes, and zoning codes.

This chapter provides an overview of prevalent contem-porary land use types. Residential and select nonresidentialbuilding considerations are presented in isolation of eachother. Although this format may be considered anathemato proponents urging greater integration of potentially com-patible or supportive land uses, extensive discussion of suchendeavors, even in the context of current mixed use andplanned developments, is not the objective here. Rather,identifying some of the base considerations associated withselect land use types may provide a cursory foundation forbetter appreciating and identifying what may be unique toeach use and how they may be best integrated.

A variety of factors determine the type and configurationof a given land use, including the expectations of landown-ers, users, and consumers; the availability of land; the costof construction; the natural attributes of the site; and thecharacter of the surrounding community. These are modi-fied to a great degree by local regulations, which are basedlargely on more encompassing issues of health, safety and



Source: LAND DEVELOPMENT HANDBOOK

194 C O N C E P T U A L D E S I G N

welfare, local considerations relative to the nature of localcommerce, prevalent community attitudes, and past com-munity practice.

An examination of the zoning ordinance in all but thesmallest communities reveals great variety in the categoriesof permitted land uses. Typically, this includes residential,commercial (sometimes broken down into retail and officeuses), and industrial uses. Depending on the size, location,and maturity of the community, a jurisdiction’s zoning doc-ument may establish other land use categories to reflect itsunique economic base, such as manufacturing, agriculture,maritime, mining, forestry, and institutional uses, to cite afew. Furthermore, the zoning ordinance, as discussed else-where in this book, normally identifies a series of de-velopment standards, commonly expressed as minimumrequirements focusing on such elements as lot size, buildingheight, yard requirements, open space, and imperviouscover.

That architectural styles vary in different geographicregions in the country is no surprise. Regional variation inhistory, culture, and heritage affects development patternsin density and configuration as well. Different names areoften used to describe similar types of land use.

Most local regulations are extremely specific concerningpermitted density, height, bulk, and setback requirementsfor most land uses. To attempt to assemble and reproducethis wide range of specifications would be neither produc-tive nor useful. The discussion of land uses, developmentintensities, and the design principles in this chapter is in-tended as a primer.

If there is a common denominator throughout contem-porary development, it may be its heavy reliance on theautomobile as the principal means of transportation. Thesuburban development pattern is characterized by a strongdependence on the car for both work- and leisure-basedtrips. Historically, the separate clustering of residential andemployment areas at density levels low enough to makepublic transportation infeasible have reinforced this. Thesingle-occupant automobile continues to be the most prev-alent form of transportation in the suburbs. This phenom-enon places a unique set of requirements on resulting landuse types and development patterns. Attention to a com-mon need for both vehicular circulation and on-site parkingis necessary. Streets and roads provide the common linkagebetween and within land uses and the principal frameworkof the resulting development patterns. Similarly, parking re-quirements for the automobile are a major design elementin the sizing and organization of individual land uses.

DEVELOPMENT TYPESIdeally, a community seeks to guide its growth in a mannerconsistent with its heritage, common goals, and economicinterests. Local land use activity is guided by comprehen-sive or master planning, representing a compendium of pol-icies, usually subjected to arduous public participation,focusing on topics such as population and economic

growth, housing, transportation, community facilities, andland use. While a comprehensive plan may contain amapped graphic representation of what the communitymight look like at some point in the future, the local zoningordinance and zoning map are the tools that provide theday-to-day implementation effecting land use decisions rel-ative to the overall comprehensive plan policy objectives. Aclear understanding of the distinction between these doc-uments is imperative to understanding the extant land usepatterns associated with development activity in any givencommunity. Decision-makers in land development and de-sign must be sensitive to the rationale for the type and useintensities identified in the comprehensive plan. They mustalso be fully apprised of the design standards and criteriagoverning the size, form, and character of proposed devel-opment, as identified in the local zoning ordinance andsimilar regulations.

It may be useful for the novice to consider a local com-munity as a single large planned community. The compre-hensive plan and its associated policy statements representthe collective public vision to guide community growth.Various ordinances and regulations provide the means toimplement that vision. Together they provide the two im-portant elements that establish the foundation for land de-velopment patterns in a community.

Historically, zoning ordinances have relied on the delin-eation of distinct geographic zones or districts that accom-modated the development of one land use type. Thesedistricts generally included residential, commercial (nor-mally inclusive of office and retail uses), and industrial cat-egories. Subcategories of each use may stipulate gradationsin density within a land use, prompting alternative devel-opment patterns or building programs. While much landactivity is rooted in a single zone/single use developmentpattern, more flexible development patterns and land usecombinations are fostered by development controls thatperpetuate planned, planned unit, and mixed use devel-opments. The objective of these latter categories move be-yond singular use and attempt to foster a framework forgreater variety in permitted land uses and arrangements.Prior to discussion of individual development types, it willbe valuable to outline briefly some of the more encom-passing planning terms.

Conventional SubdivisionThe historic basis for much suburban land use is the con-ventional subdivision, created by the division of larger landtracts into smaller land units. Such subdivision generallyrequires new streets for accessing the newly created smallerland units or lots. The subdivided acreage provides individ-ual lots for houses and lots or parcels for nonresidentialuses. While subdivisions have become varied in pattern, lotsize, street alignment, open space network, and in somecases a mix in permitted land uses, conventional develop-ment continues to be predicated on the simple subdivisionof land. It has been the mainstay of suburban residential



DEVELOPMENT PATTERNS AND PRINCIPLES

12 � DEVELOPMENT PATTERNS AND PRINCIPLES 195

F I G U R E 1 2 . 1 Conventional subdivision. F I G U R E 1 2 . 2 Cluster subdivision.

development and accommodation of proximate retail, em-ployment, and public facilities.

The larger tract acreage is divided in a manner that pro-vides for complete transfer of land ownership to subsequentusers. Streets are normally incorporated into public own-ership, and community open space, if provided, may bedeeded to an appropriate public or semipublic entity. Singleor multiple builders may on a lot-by-lot basis, initiate con-struction. Figure 12.1 below represents a typical conven-tional subdivision.

Cluster SubdivisionCluster development relies on subdividing larger propertiesinto smaller lots or parcels, but differs from conventionalsubdivision in that it typically results in a land plan with agreater percentage of the overall acreage set aside in com-mon, community, or conservation open space. To achievethis open space, local regulations generally allow a reason-able reduction in individual lot size and associated setbacks,provided there is no increase in the overall number of lotsthat would otherwise be permitted under comparable con-ventional subdivision. The resultant land area not placed inindividual building lots is normally devoted to commonopen space. This development pattern allows for the con-centration of building activity on the more usable areas ofa site and ideally results in a reduction in development costsassociated with site grading and supporting infrastructure.Cluster subdivisions are also often used to protect environ-mentally sensitive areas of a given site. The reduction inindividual lot size and associated exterior yards is compen-sated for by the communal open space that is made avail-able.

Cluster subdivision requires increased attention to thedetails of design. Reliance on smaller lots necessitates regardfor other methods of maintaining privacy and buffering be-tween residences. Often greater controls are placed on unitdesign and orientation. Design controls often exceed stan-dards enumerated in zoning and subdivision regulations. Itis common for cluster development to be executed asplanned developments, as discussed below. A typical clustersubdivision is presented in Figure 12.2.

Planned Unit Development (PUD)A planned unit development (PUD), as its name implies,is planned as a single entity and usually represents someminimal-sized contiguous acreage, as specified by localordinance. It contains single or multiple residential clustersor planned units with provision for public, quasipublic,commercial, or industrial areas. Normally, nonresidentialuses are provided in a ratio to residential uses, as stipulatedby ordinance. Planned unit developments generally providefor a mix of housing types and land uses and situate de-velopment within an overall open space system, with anemphasis on amenity provisions and preservation of naturalresources. Figure 12.3 is representative of a planned unitdevelopment.

Planned Community or Master Planned CommunityThe planned community usually provides for a wider rangeof residential land uses and includes commercial-retail, em-ployment, recreation, and institutional uses to create abalanced hierarchical community. Planned communitiesrepresent large land assemblies that attempt to satisfy a full





F I G U R E 1 2 . 3 Planned unit development.





range of lifestyle and support elements to sustain its resi-dent population. Normally, development is undertaken bya single owner or master developer who in addition to or-chestrating the financing, planning, and design of a projectmay construct the required infrastructure and communityamenities, making sites available to others for individualbuilding construction. Figure 12.4 represents a masterplanned community.

DEVELOPMENT CONSIDERATIONSA development team must consider the effect that each typeof land use has on environmental, aesthetic, financial, op-erational, and marketing characteristics of a land develop-ment project. They should understand the relationshipbetween these characteristics and their effect in offsettingthe impacts of development. These may range from physicallimitations inherent in the site to a community’s predispo-sition to a proposed program of land development. Follow-ing are some characteristics that warrant consideration intheir implications on resulting land use patterns.

Generally, there is a direct relationship between the in-tensity and density of development and its impact on thesite and surrounding community. These concerns may focuson the following:

Environmental Impacts and Opportunities

� Site disturbance: More clearing and grading is re-quired as buildings, site improvements, and infrastruc-ture occupy an increasing proportion of land. There isnormally a reduction in the opportunity to retain natu-ral grade as density increases. Opportunities to pre-serve existing wooded or natural areas are similarlyreduced as building program coverage is expanded.Lower building density does not in itself result in lessimpact. It is the combination of existing conditions,proposed program, and resolution of program detailthat eventually delineates the degree of impact. Anequivalent program in a more compact developmentenvelope can have substantially less site disturbanceimpact than a comparably sized program dispersedover a greater amount of acreage. Similarly, buildingprograms that are tailored to unique site conditionscan have less impact on land than generic solutions.For example, a residence designed for a steep site willhave a better fit and require less grading than oneoriginally designed for level terrain.

� Stormwater management: As the impervious surfaceassociated with a given development program in-creases, so does stormwater runoff, along with the in-creased potential for non-point source pollutants.Conversely, greater opportunities exist for storm drain-age control, erosion and sediment control, and bestmanagement practices, in that higher density can assistin financially compensating for construction costs asso-

ciated with these mitigation measures. The concentra-tion of density within a site may require less extensiverequired mitigation activity, or at least contain it.

Aesthetic Impacts and Opportunities

� Context: Compatibility with adjoining land uses canbecome problematic as proposed development intensityincreases. Careful site planning and design can assist inmitigating this problem. Structural solutions may becostly, and buffering solutions may be land consump-tive.

� Architectural design: More intense development gen-erally requires more stringent architectural controls toensure overall visual coherence. Modest building ele-ments on large lots or parcels benefit from distance be-tween improvements. Individual units capture theirown identity and are less visually and functionally de-pendent on their neighbor. As building size increasesor parcel size decreases, increased proximity warrantsgreater attention to issues of compatibility.

� External views: Larger buildings or more intensebuilding programs may impact the extent and qualityof exterior views. Denser development requires carefulsite planning to ensure privacy and minimize thevisual and noise impact of abutting uses.

Financial Impacts and Opportunities

� Infrastructure: While higher-density developmentgenerally requires higher total infrastructure costs, itmay result in lower construction, operation, and ser-vice costs on a per unit or square foot basis.

� Land: Higher-density development permits landcosts to be distributed within a larger developmentprogram, resulting in lower per unit land costs.

� Site amenities: Although higher density may requirea more elaborate amenity program, the increased pro-ject development yield and resulting revenue may pro-vide an incentive for such provisions.

� Construction: Typically, more intense developmentresults in higher total construction costs. It may fostercertain economies in construction due to the potentialfor distributing costs over a larger program base. Con-centrated building programs generally provide a lowerper unit construction cost than a similar program dis-persed over a larger area. Such reduction results fromsavings associated with a more compact building enve-lope and shorter lengths of expensive infrastructure.

� Public / semi-public facilities: Aggregate and per unitoperation and maintenance costs of select facilities maybe reduced with denser development patterns. This isparticularly important for major capital facilities, such





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F I G U R E 1 2 . 5 Typical conventional lot.

F I G U R E 1 2 . 6 Typical cluster lot.

as a sewerage treatment plant. These may be fundedby municipal bonds or special assessment or develop-ment association fees and rely heavily on project usageto retire debt. The building of major private facilities,such as utility transmission lines, also relies on de-mand to justify new construction.

� Tax revenue: Tax revenues generally increase on anacreage basis as a result of public and structural im-provement, and subsequently increased density nor-mally results in a higher average per acre assessedvalue.

� Municipal service: Public service improvements canmore readily be supported by concentrated populationand development patterns, which afford a more effi-cient delivery system.

Operational Impacts and Opportunities

� Maintenance: Occupants realize lower per unitmaintenance costs due to economies of scale associatedwith larger, more intense development patterns.

� Energy: Per unit energy cost savings are generallyrealized in development that is more compact.

Marketing Impacts and Opportunities

� Market exposure: Increased scale, intensity, or qual-ity of development may foster a visual presence, whichtranslates into greater market exposure. Depending onthe actual development program, this may increaseproject appeal to a broader spectrum of the market orincrease awareness among targeted consumer groups.

� Community identity: Larger-scale developments canprovide additional justification for amenities, whichmay, in turn, increase community identity andresident/ tenant affinity with a project.

RESIDENTIAL LAND USETypically, housing is the most prevalent land use within ajurisdiction. Residential design requires sensitivity to thepragmatics of sound construction economics, an under-standing of site conditions, and an appreciation for con-sumer lifestyle preferences. Similarly, sound residentialplanning and design requires a genuine appreciation for theindividual dwelling unit.

Single-Family DetachedIn a single-family detached residential dwelling, each indi-vidual living unit is a freestanding structure. Each dwellingunit normally occupies a separate recorded lot. In a con-ventional lot arrangement, the single-family home is sur-rounded on all sides by property or yards reserved for theoccupant’s exclusive use. The lot must meet a minimum oraverage size prescribed in the community’s zoning ordi-

nance. Similarly, in a cluster lot, the single-family structureis surrounded on all sides by yards reserved for the occu-pant’s exclusive use; however, the lot may be smaller thannormally prescribed under conventional zoning and theyard setbacks are generally lessened. Figure 12.5 is repre-sentative of a typical conventional subdivision lot, and Fig-ure 12.6 represents its cluster equivalent.

Utilization of cluster lots requires greater attention tohouse siting and house-to-house relationships, given theneed to preserve individual unit privacy and maintain com-munity design standards among smaller average lot sizes.The benefit of cluster development rests with the potentialreduction in per unit infrastructure costs, given the aggre-gation of dwellings on only a portion of the project acreage.Similarly, the conservation of community open space incluster arrangements and its amenity appeal may offset mar-ket concerns about smaller lot sizes and the potential re-duction in individual unit privacy. Conventional or clusterarrangements alone do not dictate lot size. Relatively speak-ing, large and small house types may be developed in eitherarrangement. While acre and multiple-acre home sites arecommon in suburban areas, more typical single-family de-tached lots ranged from 1⁄4 to 1⁄3 acre in size throughoutmost of the last several decades. However, current trendsare moving toward smaller lot sizes, given escalating landcosts and changing lifestyle requirements. Single-family de-





F I G U R E 1 2 . 7 Example of variation in lot size due to site char-acteristics.

F I G U R E 1 2 . 8 Example of the use of flag lots in lieu of extendedstreet length.

tached dwellings on 2000–5000-ft2 lots are increasinglycommon in both in-fill developments and planned com-munities.

Lots are normally square or slightly rectangular in shape.Minimum lot widths are generally governed by local zoningordinance. Decisions to exceed that dimension are oftenprompted by market demand for additional distance be-tween dwelling units, the dimensions of the proposedhouse, or preferred driveway approach to the garage. Anattached side-loaded garage requires a wider lot than a sim-ilarly sized front-loaded facility.

Lot lines normally run perpendicular to the street front-age. Variations in lot configuration commonly include pie-shaped lots around cul-de-sacs and flag or pipestem lots.The latter convention provides limited lot width along thepublic street frontage to accommodate driveway access anda widening of the lot at the building setback line sufficientto satisfy the desired house type and its yard requirements.Examples of these lot configurations are presented in Figure12.7.

Pipestem or flag lots were originally designed to allowaccess to otherwise landlocked parcel acreage. Use of thistechnique recognizes the environmental and economic ad-vantage in substituting private drive lengths to tap land thatotherwise would require additional street length and poten-tially greater site disturbance and infrastructure costs. Thenegative attributes of this technique include the potentialburden on homeowners to individually maintain longerdriveways or private street lengths, potential access con-straints for emergency vehicles, and possible undesirablehouse-to-house relationships, as pipestem dwellings may beperceived to be in the rear yards of adjacent residences.However, judicious use of pipestem lot arrangements canprovide distinct benefits in residential design when its use,resulting lot size, dwelling orientation, and access consid-

erations are based on sound site planning and communitydesign criteria.

Zoning ordinances generally provide setback and yardrequirements for single-family residential development toensure functional side, rear, and front yards. Front yard set-backs are generally a minimum of 20 to 30 ft to accom-modate the length of a parked vehicle in the driveway. Frontyard setbacks may vary depending on the nature and scaleof the adjacent street. Lesser setbacks may be acceptablewhere alternative parking arrangements are provided, as isthe case where rear-accessed alleys or service drives are em-ployed. Deeper setbacks may be required along more heav-ily traveled arterial streets than on neighborhood streets orcul-de-sacs with less traffic volume.

Demand for affordable single-family detached housing ina time of escalating land prices has prompted greater reli-ance on smaller lots. The smaller lot size not only appealsto builders and developers who can realize lower per unitinfrastructure costs and higher per acre unit yields but re-sponds to consumer preference for the reduced mainte-nance requirements associated with the smaller yards.Smaller lots in well-designed communities with provisionsfor common amenities appeal to a lifestyle that seeks con-venient accessibility to diverse leisure activities. Safeguardsto a well-designed small lot community reside in well-conceived architectural design of the unit and sensitive siteplanning.Design Considerations. While conventional subdivisionregulations normally prescribe setbacks for front, rear, andside yards, dwelling unit design, variation in lot sizes, lotdimensions, and concessions suited to cluster or uniquedetached housing prototypes provide opportunities to tailordesign to local market and site conditions. Several groundrules can provide a strong foundation to residential layoutdesign. These include:





F I G U R E 1 2 . 9 Example of variation in lot size due to site char-acteristics.

� Lot and place houses in a manner that responds tothe site’s natural features.

� Avoid extremes in either random plan organizationor uniformity to the point of monotony in the patternof development.

� Establish appropriate block lengths to minimizelong views of repetitive house-fronts, garages, anddriveways as well as foster convenient vehicular andpedestrian movement.

� Ensure yard dimensions and unit orientation thatpromote individual dwelling legibility and sufficientyard privacy.

� The street pattern should result in a coherent andlegible circulation system to support an identifiablesense of place.

� Building setbacks should reinforce the street hierar-chy.

Single-Family SemidetachedThe single-family semidetached dwelling, commonly re-ferred to as a duplex unit, consists of two living units thatoccupy a single structure separated by a common wall. Eachdwelling has its own exterior entrance and is located on aseparate recorded lot. Each dwelling unit is surrounded onthree sides by property reserved for the occupant’s exclusiveuse.

Single-Family AttachedSingle-family attached dwellings include housing types withmultiple dwellings in a building arrangement where two ormore dwellings share common walls, and in some cases

common floors and ceilings. Each unit has a separate pri-vate entrance at grade level and usually a contiguous ex-terior yard reserved for the occupant’s exclusive use.Variations may include:Townhouse (Row House or Townhome). Made up of threeor more units attached side-by-side, the townhouse, long acommon urban housing prototype, has become a popularcomponent of the suburban housing market. A common orparty wall separates individual units, each with an at-gradeentry. Property on at least two sides, normally front andback, is generally reserved for the occupants’ exclusive use.

The townhouse provides flexibility in plan and style,with design variations that include integral or detached ga-rages. Indoor/outdoor relationships generally focus on therear yards, although they may orient to small front court-yards. Exterior yard privacy may be enhanced with land-scaping, fencing, or privacy walls. Lot widths can varydepending on the desired character of the unit. While con-ventional suburban townhomes may range from 16 to 24ft wide, units of 32 ft or greater are not uncommon whenmarket considerations warrant a street presence approach-ing that of a single-family detached residence. At the moreconservative widths, lot depths may range from 60 to 100ft. Densities normally range from 7 to 12 units per acre.Depending on the unit width, parking requirements, siteconditions and desired community character, densities ofup to 20 units per acre are not uncommon in more urbansettings. The figures below illustrate a range in townhouseconfiguration, including the more conventional front-loaded unit, courtyard or clustered townhouse court, andalley-served units.

Each townhouse dwelling has a separate front door, al-though end units may be side entry. Generally, each househas its own utility connections. Typically, local ordinancesprescribe the maximum number of side-by-side units thatmay be aggregated into a single townhouse ‘‘stick’’ or build-ing group. While sticks of six to eight townhouses havebeen a common development practice, combinations ofthree to four units, comparable in scale to a large single-family residence, are popular in some high-end market seg-ments.

Building lengths with more than eight attached units aremore commonly found with narrow, 18-ft or less averageunit widths. Shorter lengths, and a higher percentage of endunits are generally associated with wider upscale town-homes or in instances where parcel dimensions precludelonger lengths.

While the urban townhouse was configured in a lineararrangement with units oriented to the street, the suburbantownhouse community has taken on a more organic ar-rangement. This has occurred in response to site conditions,which have accommodated a more expansive layout, as wellas a proclivity toward arrangements in which the units’fronts face towards the parking lots and whose rears areopen-space amenities. The urban street setting, with its at-tendant parallel parking and supplemental rear service alleyaccess, had been preempted, in the suburbs, by the front





F I G U R E 1 2 . 1 0 Typical townhouse condition.

service drive and its associated perpendicular parking. Var-iations do include townhouse layouts, which focus on acourt and mews arrangement of units. The former generallyresults in a cluster of townhomes fronting on a commonparking area, often referred to as parking court or parkingbay. The common vehicular circulation area serves as theorganizer for the cluster. The mews arrangement focuses ona pedestrian open space to organize the front facades of theindividual townhomes, with parking occurring at the ter-minus of the pedestrian area or on the rear or underside ofthe units.Back-to-Back Townhouse. While considered an attachedmultifamily housing type in many jurisdictions, the back-to-back townhouse often divides the length of a traditionaltownhouse stick with an additional common wall thatserves to separate units organized along opposing facades.The resulting aggregate building form has two front yards.The double frontage prompts a need for careful site plan-

ning to ensure the convenient placement of adequate park-ing for each unit. Reliance on a single exterior exposure foreach residence requires subtle design considerations to bal-ance the semipublic nature of a front entry with any privacyrequirements associated with the singular exterior livingspace, which occupies the same facade.Other Townhouse Variations. Another variation to thetownhouse is the stacked or piggyback townhouse. Thismay include a multistory townhouse unit over a single-storyflat or a multistory townhouse over a similar multistoryunit. Such arrangements work well on sites where topo-graphic change will allow upper and lower units to be ac-cessed at grade on opposing sides of a building. In extremeinstances, the lower unit may be reduced to a single exteriorexposure.

Alternating townhouses with stacked flats in the samebuilding can produce additional diversity. The flats, some-times referred to as coach homes may be located either atbuilding ends or in interior locations. This arrangement isoften classified as a multifamily residential product subjectto zoning requirements associated with that use category.Figures 12.13 and Figure 12.14, respectively, illustrate thecombined townhouse/coach house and piggyback/stackedtownhouse.Multi-Plex. Used with a prefix representing the numberof attached units, such as duplex, triplex, quadraplex, etc.,multiplex residences consist of two or more units in variousconfigurations, each with its own separate at-grade exteriorentrance. Piggyback townhouses and manor houses are of-ten considered multiplex units. The yards surrounding atypical multiplex unit may be reserved for common occu-pant use or portions of the yards may be designated for anindividual unit’s exclusive use. Figure 12.15 shows a varietyof multiplex combinations.

As the number of units in this type of attached residen-tial arrangement increases, unique opportunities and con-straints in both design and construction arise. Unit design,solar orientation, indoor/outdoor relationships, privacyprovisions, convenience of automobile access, and parkingmust be weighed against the increase in density and reduc-tion in per unit land, construction, and infrastructure costs.

Multifamily ResidentialMultifamily structures are characterized by four or moreunits in a single building, with units sharing access to theexterior by one or more common entrances. Structures maybe one or more stories, and multifamily communities ordevelopments may consist of one or more buildings on asingle tract or lot. Structures are surrounded by commonopen space, which often contains on-site recreational facil-ities for resident use. Private drives or service roads provideaccess to surface parking lots or in some cases structuredparking, private garages, or carports.

Most zoning ordinances specify detailed design criteriaand development standards for multifamily projects. Projectdensity is usually set as a maximum number of dwellingunits per acre or, in some instances, may be expressed as a





F I G U R E 1 2 . 1 1 Traditional townhouse unit arrangement.

maximum permitted square feet of building or floor areacoverage per acre of land.

Minimum standards are adopted to guard against over-crowding, ensure access to light and air, protect privacy, andensure compatibility between land uses. Most jurisdictionsseek to locate multifamily residential development in areaswhere land costs are high. Typically, this type of develop-ment coincides with areas of considerable existing orplanned investment in public infrastructure, or where prox-imate commercial retail and office activity would benefitfrom higher-density residential development. In this regard,multifamily housing often provides the buffer between non-residential activity and single-family attached and detacheddevelopments.

Due to the more intense traffic generation resulting fromthe higher densities associated with multifamily housing,convenient access to major collector or arterial streets isdesirable. Depending on the size of a development, localfire and public works officials may require at least two en-trances or connections to a public street. This allows access

to be maintained in the event that one entrance becomesobstructed.

Site planning for multifamily developments requires anappreciation and understanding of the proposed buildingdesign. The higher densities, size of structures, and rela-tionship between structures and site elements leaves lesslatitude than may be afforded in site design for less denseresidential housing types. The placement of driveways, lo-cation and sizing of parking areas, and other infrastructureconsiderations require knowledge of building dimensions,elevations, and orientation.

Multifamily structures are generally categorized as eithergarden or low-rise, mid-rise, or high-rise structures. Dis-tinctions and characteristics of each of these are describedbelow.

Garden apartments, sometimes referred to as walk-up orlow-rise, consists of one- to four-story structures. The in-dividual apartment units may be arranged along corridorsor around common stairwells, which may be enclosedwithin the structure or unenclosed and integrated into the





F I G U R E 1 2 . 1 2 Back-to-back townhouse.Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com)

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F I G U R E 1 2 . 1 3 Combination townhouse and coach house arrangement.

F I G U R E 1 2 . 1 4 Piggyback or stacked townhouse.

exterior architectural design. While some units may havedirect private entrances at grade level, normally units sharecommon entries. As the name implies, the garden apart-ment focuses on melding the dwelling unit to the buildinggrounds. The building units are generally organized aroundlandscaped open space and parking areas. Ground floorunits may have direct access to exterior patios or gardenareas, and upper floors may have balconies or terraces, pro-viding each individual unit with exterior living space.

Garden apartment building configurations vary depend-ing on a myriad of marketing, program, and site consider-ations. They can range from single-loaded buildings in

which the individual unit runs from the front to the rear ofa building (through-units) to double-loaded arrangementswhere in each unit has a single (front or rear) exposure. Interms of site design, awareness of interior room organiza-tion and relationship to exterior space is important to pro-mote desirable views and to enhance individual unitprivacy. This is particularly important where parking is con-centrated near the building. Provision of intermediate land-scape between the unit and the parking area enhances thelivability of the dwelling, particularly if it is the unit’s soleexterior exposure. Figure 12.16 illustrates single- anddouble-loaded garden apartment layouts.





F I G U R E 1 2 . 1 5 Typical Multiplex Combinations: triplex, quadraplex, eightplex.

F I G U R E 1 2 . 1 6 Example of double-loaded and single-loadedgarden apartments.

Garden apartments afford significant flexibility in site de-sign due to the adaptability of various building forms todivergent site conditions. Unit densities can range from 10to 20� units per acre, depending on the building config-uration, unit sizes, number of stories, parking, open space,and amenity packages. In an effort to appeal to varyingmarkets, garden apartment communities increasingly pro-mote amenity packages that expand beyond the traditionalswimming pool to include facilities complete with spas; ex-ercise, game, meeting and community rooms; and ex-panded site improvements including tot lots, court facilities,trails, and park courses. Multifamily residents increasinglydesire amenities comparable to those provided in singlefamily residential communities. Even sheltered parkingsuch as carports, or more infrequently individual garages,is an increasingly popular element in select garden apart-ment communities.

Mid-rise and high-rise multifamily residences are generallyfour- to eight-story structures. High-rise residences nor-mally exceed eight stories. Both rely on elevators for verticalcirculation. Individual dwelling units access common cor-ridors. Units are generally arranged along opposite sides ofthe corridor, providing a single exterior exposure for theprincipal interior living spaces. While the economies ofconstruction weigh heavily in favor of this arrangement,unique market considerations may prompt alternative de-sign, such as single-loaded corridors, as in the case wherea unique amenity mandates that all units have comparableexposure to the attraction.

Internally, buildings are organized around the elevator,utility, and a stairwell core, which may be central to thebuilding floor plate. Entered at a common lobby, or mul-tiple lobbies at differing levels, if terrain permits, the cor-ridors penetrate the building extremities providing accessto the individual residential units. Additional stairwells po-sitioned at the further reaches of the corridor provide analternative means of access /egress. The concentrated needfor service and delivery is generally satisfied by a centralloading area, which is often located to the rear or side ofthe building removed from main tenant access and view.Figure 12.17 is illustrative of a typical mid- and high-risemultifamily floor plate.

Four- to eight-story multifamily buildings can achievedensities of 30 to 40� units per acre. Provision for parkingincreasingly relies on subsurface or structured arrangementsto maximize land use efficiencies and promote tenant con-venience and safety.

Many of the amenity provisions of mid- and high-riseresidential buildings may be internal to the structure, butexterior elements may include a full range of recreationaland leisure activity areas. In more urban settings, this mayinclude indoor or rooftop swimming pools, landscaped ar-rival courts, and lush landscaped perimeters. On more ex-





F I G U R E 1 2 . 1 7 Typical mid-rise and high-rise multifamilyhousing floor plate.

pansive sites, the provisions may include tennis courts,elaborate pool facilities, and exterior exercise and recreationofferings in a park-like setting.

Site Design: Residential DevelopmentLocal zoning codes and planning documents generally pro-vide the principal guidelines and criteria governing residen-tial development patterns. These include stipulations as tomeans and methods for ensuring code compliance. Someof the more conventional considerations normally include:

� Maximum permitted density, including means andmethod of calculation. Density calculations may requirethe omission of all or portions of a site area encum-bered by environmental constraints such as steepslopes, floodplain, wetlands, major utility easements,and public rights of way

� Minimum acreage assembly for select residentialtypes. Often cluster or planned development districtsrequire a minimum amount of acreage to be eligiblefor that zoning district

� Minimum yard requirements, including front, rear,and side yard requirements, may be expressed as aminimum dimension or relationship to the height ofthe building

� Minimum open space provisions, including poten-tial distinction among usable open space, dedicatedopen space, and common green space. Ordinances maydiscount or cap the amount of public open space al-lowed as part of the project open space calculation.Similarly, a percentage of the total open space mayneed to meet certain location, distribution, or perform-ance criteria, such as size, shape, and topographic con-siderations, or be exclusive of floodplains, utilityeasements, or wetlands

� Screening and buffering standards, given the spe-cific use or use intensity proposed in relationship tothe nature and density of adjoining uses

� Maximum lot coverage

� Minimum lot dimensions and frontage require-ments, including distinction between interior and cor-ner units / lots, pipestem or flag lots, and cul-de-sac lots

� Maximum number of pipestem lots permitted

� Lot restrictions regarding inclusion of environmen-tally sensitive areas and utility easements

� Parking and access criteria, which may include thenumber of parking spaces required, limitations onpublic or private street length, and street loading ca-pacities

� Maximum building height and methods for calcu-lating height

� Minimal landscape or tree canopy requirements

In attached and multifamily housing types, considera-tions may include:

� Minimum unit width or size

� Limitations regarding maximum number of unitsthat may be grouped together

� Maximum distance between unit entry and parking

� Variation in architectural facade and setbacks

� Minimum setback from common property lines

� Minimum distance between buildings

� Standards and criteria for determining the numberand placement of loading and service areas

� Building and fire code requirements

NONRESIDENTIAL LAND USEPrincipal nonresidential development in the suburban en-vironment focuses on retail, office, and industrial land uses.The following discussion highlights the more prevalentbuilding types and site considerations appropriate to each.

Market ConsiderationsProvision of retail, office, and industrial development pro-grams can be prompted by a myriad of factors, includingobservation of a demonstrated need for local distribution ofgoods and services at a neighborhood or community level;recognition of an opportunity to fulfill a local jurisdictionsdevelopment goal in expanding either local or regional ec-onomic base; or recognizing local trends focusing on thegrowth, consolidation, or relocation of business ventureswithin an area. Regardless of the genesis or justification forsuch facilities, site design and site execution must be si-





F I G U R E 1 2 . 1 8 Example of comparable floor area ratios.

multaneously sensitive to the requirements of the provider,prospective tenant and patron, site, and surrounding com-munity.

Design ConsiderationsAs with all land development activity, commercial site de-sign criteria stem from two principal sources. The first con-sists of standards associated with the prospective use. Thisincludes the spatial characteristics and site provisions req-uisite to housing and servicing the facility and its tenantsand customers. The second set of criteria concentrates onlocal land development plans and controls. While the zon-ing ordinance is the primary gauge for establishing site per-formance, other considerations, such as environmental, fire,and safety compliance, factor heavily into facility and sitedesign. This set of criteria may vary among jurisdictionsand the nature and intent of the specific land use underconsideration.Common Standards. Subsequent to determination thatthe proposed use is appropriate for a given property, set-back, height, bulk, and other dimensional and performancestandards constitute the principal site design criteria. Thesestandards are normally contained in most jurisdictionalsubdivision and zoning regulations.Floor Area Ratio. Nonresidential development is most fre-quently programmed and sized on the basis of the aggregatesquare feet of built structure relative to development sitearea. The common method of computation is the floor arearatio (FAR), a method of measurement expressed as therelationship of total building square feet to the total sitearea. For example, as shown in Figure 12.18, a 10,000-ft2

building located on a 40,000-ft2 parcel would constitute afloor area ratio of 0.25 (building area divided by parcelacreage). The number of floors associated with the builtproduct does not influence the floor area calculation. In thecited example, the 10,000-ft2 building might be constructedas a two-floor building of 5,000 ft2 each, or a four-storybuilding of 2,500 ft2 each. The floor-area-ratio is 0.25 in allcases. Most jurisdictions do not include parking structuresin floor area computations. Similarly, exclusions may in-clude portions of the building that are below grade or spaceprogrammed for select circulation, service, and support fa-cilities. It is important to be aware of the method for cal-culating FAR in each jurisdiction.Lot Size and Bulk Regulations. Minimum lot size, build-ing height, bulk, setback, and yard requirements are nor-mally stipulated in the individual zoning categories fornonresidential uses. The criteria generally vary in relationto the intensity of the desired development and the char-acteristics of the adjacent land use. Areas designated asmore urban will normally require smaller setbacks fromparcel boundaries. While a maximum building height maybe stipulated, the permitted height of a structure may begoverned by performance criteria. A common method ofcontrol focuses on maintaining a relationship of building

height to peripheral yard setbacks. If an acceptable angle ofbulk plane from the top of building to a given property orparcel line is designated, the setback can increase propor-tionately as the building height increases. For example, arequired 40� angle of bulk plane might require a 17-ft set-back for a 20-ft high building and a 34-ft setback for a 40-ft tall building. Other jurisdictions may express a minimumyard setback based on a given building height and simplystipulate that for every additional foot of building heightthe setback dimension will increase a set distance. Figure12.19 illustrates the concept of angle of bulk plane for reg-ulating building height.Parking, Loading, and Service. Criteria governing mini-mum parking, loading, and service are normally expressedin relationship to the floor area of the proposed buildingprogram. Typically, the zoning ordinance stipulates thisstandard as a minimum number of parking spaces to beprovided on-site, although in some cases a portion of theparking may be provided off-site or in combination withadjacent uses. Jurisdictions vary in terms of how they ex-press this relationship. It may be based on gross buildingsquare footage, net building square footage, net leasable ortenant area. The designer must understand the method ofcalculation, ascertain the minimum requirement based onpublic standards, and ensure that such a minimum provi-sion has client and market acceptance. Unique program re-





F I G U R E 1 2 . 1 9 Illustration of angle-of-bulk plane.

quirements or marketing considerations often prompt aneed for parking and loading space provisions to be in ex-cess of the minimum zoning criteria.Landscape and Open Space. For nonresidential uses, thisis typically expressed as a percentage of the total site areathat is not encumbered with the building, vehicular circu-lation, and parking. While it is normally considered theresidual portion of the site remaining for landscaping, insome localities it may be more conservatively delineated toexclude pedestrian walkways, patios, and similar site im-provements, which are deemed impervious surface treat-ments. Landscape requirements are generally categorized astwo main types.

Peripheral yard and buffer area requirements may bestipulated for nonresidential projects, which are deemed in-compatible with surrounding land uses. These may be pre-scribed as a fixed dimensional width with certain pro formalandscape treatments or as a performance criteria requiringa combination of plant material and/or structural elementsthat provide an equal or improved buffering condition.

A second set of standards focuses on minimum land-scape improvements required given specific developmentprogram components. These may deal with shielding orscreening of parking areas, service and loading zones, min-imal streetscape standards, foundation planting, parking lotlandscaping, or other specific concerns of the local juris-diction.

RETAILRetail development may be loosely categorized according tothe size and physical characteristics of the proposed facility.The principal types of retail locations include freestanding,strip, center, and mall arrangements of sales and accessoryuses.

FreestandingThe freestanding retail establishment has taken on reducedimport in the suburban market, given trends focusing onthe aggregation of retail uses and the benefits associatedwith collective marketing, expanded visibility, and customercapture associated with more encompassing retail or mixeduse projects. Where a freestanding retail use does exist, itis generally positioned to respond to several sets of locationcriteria. It may be an establishment, sited on a separaterecorded lot or parcel, that is part of a larger communityof like uses, such as a town or village center or in a lineararrangement along a major road or highway. It may consti-tute a modest forerunner retail service in a geographic areaof insufficient population concentration to warrant more ex-pansive retail development. It may represent a national orlocal business with a sufficiently unique market to generatepatronage at a location apart from other retail trade orwhose functional requirements are best satisfied as a free-standing structure.

In today’s suburban retail market, freestanding retail es-tablishments are commonly associated with locations withinor proximate to larger retail or shopping center. Establish-ments such as restaurants, banks, movie theaters, bowlingalleys, gasoline stations, office buildings, and similar sin-gular operations may be located on separately recorded lots,sometimes referred to as pad sites, within the parking areaor along the road frontage of larger retail centers.

The size and functional characteristics of such establish-ments vary considerably. However, building visibility, thenumber and convenience of customer parking, and the sizeand location of loading and service requirements generallyrepresent the primary site design criteria that establish thepattern for such uses. Where such a facility is contemplatedat isolated locations, one can anticipate a greater need toensure measures of compatibility with surrounding devel-opment. Integration of freestanding retail uses as an adjunctto neighboring strip, center, or mall retail development pat-terns generally presents less difficulty in ensuring commu-nity fit and may afford advantages to the extent parking,street improvements, and other infrastructure considera-tions may serve multiple users.

Strip CentersStrip centers literally represent the aggregation of retail usesin a linear arrangement, most notably with their front fa-cades paralleling roadways or positioned in an ‘‘L’’ config-uration at the intersection of major transportation routes.





F I G U R E 1 2 . 2 0 Typical strip center arrangement. F I G U R E 1 2 . 2 1 Typical retail center arrangements.

Generally, the establishments are one store deep, share com-mon interior walls, and are linked by a common pedestrianwalkway across the storefronts. The bulk of parking is ag-gregated into one or more principal parking areas normallylocated between the store facade and the street. Strip cen-ters rely on a strong visual relationship to the adjacent streetfrontage for identity and marketing. Strip retail arrange-ments can vary in size, however, once the linear distanceacross the collective storefronts exceeds 400� ft pedestriancirculation between stores begins to subside. Once a largerretail establishment, such as a major grocery store or drugstore, is introduced into a linear arrangement, the distinc-tion between strip and retail center becomes less clear. Fig-ure 12.20 illustrates the typical strip center configurations.

Retail CenterFinding definitive criteria to distinguish a retail center froma strip center can be difficult, given the negative connota-tion that the latter has acquired. Retail centers share in theirreliance on common parking areas, major pedestrian cir-culation across storefronts, and maintenance of a reasonablerelationship and visibility to adjacent roadways. A distinc-tion can best be found in the number of potential anchoror larger retail establishments that are located in a retailcenter, an abandonment of sole reliance on a linear arrange-ment for all of the retail establishments, and the introduc-tion of smaller pad site within the retail center site. Centersoften are arranged in an ‘‘L’’ or ‘‘U’’ shape, with anchor storesoccurring at the building extremities and/or central to theparking lot. These arrangements take advantage of parceldepth, and lining multiple sides of the parking area withstores reduces the distance between the parking stalls anda variety of retail establishments. The introduction of free-

standing retail establishments such as banks, gas stations,and restaurants at the center or along the roadway frontagegives a functional complexity to a retail center and requirescareful attention to site details to ensure sufficient visibility,access, convenience of parking, and service and loading.Figure 12.21 represents a typical retail center design.

Retail MallThe distinguishing characteristics of the retail mall includethe separation of major pedestrian movements from pe-ripheral vehicular parking and circulation. Generallylocated between opposing store facades, an internal pedes-trian walkway or mall may be either open or under roof.Both arrangements provide an opportunity to direct cus-tomers along expanses of intervening retail establishments.

A typical mall is presented in Figure 12.22. A normalconvention in organizing on-site vehicular circulation is toposition a service drive at the building perimeter and aperimeter road near the outer edge of the major field ofparking. Major approaches to the mall tend to be alignedwith main store anchors. In many instances, freestanding





F I G U R E 1 2 . 2 2 Retail mall arrangement.

uses (pad sites) may occupy acreage between the outer mallloop drive and the perimeter street network.

Figure 12.23 illustrates the front-sided multilevel park-ing arrangement employed at the Tysons II retail mall inFairfax, Virginia. In the background (right rear), parkingdecks have been constructed over former surface park-ing lots to accommodate the expansion of neighboringTysons I.

There is a considerable range in the size of retail malls,with major regional serving facilities often exceeding 1 mil-lion ft2 of leasable area. Increased reliance on structured

parking can assist in reducing distances between parkingareas and retail stores. The resulting site solution often en-tails the bridging of peripheral service drives around thecenter perimeter, and in the case of multilevel malls mayresult in pedestrian walkways that connect to various levelsof the center.

Retail Center Design ConsiderationsSite design for retail centers should be predicated on overallcustomer ease in identifying and locating the individual ten-ants within the center. Convenience of vehicular access, ad-





F I G U R E 1 2 . 2 3 Retail mall with structured parking. (Photo by Larry Olsen)

equacy and placement of customer parking, and safety ofpedestrian movements between parking areas and retail es-tablishments are all fundamental site planning considera-tions. A secondary set of criteria focuses on the internalservicing and operation of the center, particularly in regardto separation of service, delivery, and loading facilities. Typ-ically, reasonable convenience of parking areas (to the retailestablishment) imposes a limit on the maximum acceptabledistance between the most peripheral parking space and thecenter itself. This distance generally approximates 400� ft,the equivalent of a two-minute walk.

Beginning at the site perimeter, design considerations forretail activities should include the following:Center Orientation to Surrounding Road Network. Retailestablishments should be positioned to take advantage ofvisibility to abutting public rights of way. Leasing agentsmaintain the greatest market asset of a retail center is unob-structed visibility from adjacent roadways. In expansivecenters, the major anchors are usually singled out for thiselevated position, with smaller flanking or interior store lo-cations dependent on foot traffic generated by the anchor.There are ample examples of successful retail centers that





do not rely on excessive road exposure. It should be cau-tioned, however, that many of these more introspective cen-ters are located in planned communities, governed by siteand architectural guidelines, and operate within an envi-ronment where the location of competing establishments isstringently controlled.Sizing. The distinctions among freestanding, strip, center,and mall arrangements are related to the architectural mass-ing and organization of retail space. With the exception offreestanding retail establishments, whose size and locationmay be a function of numerous unique circumstances, thesize of the retail project and the profile of resident tenantsrelate to their intended service population. Normal conven-tions include a distinction among neighborhood centers,community centers, and regional centers. Although juris-dictions may provide precise definitions for each in theirrespective zoning documents, general definitions of each areas follows:

� Neighborhood centers generally service a populationof 2,500–40,000 or a 1.5-mile radius. They may rangefrom 3 to 10 acres in size, approximate 40,000–100,000 gross leasable square feet, and include a su-permarket or drug store as the lead tenant. Otherestablishments focus on convenient consumer access tofrequently purchased goods and services.

� Community centers, located on 10 to 40 acres, rangefrom 100,000–400,000 gross leasable square feet andservice a three- to five-mile radius and a population of20,000–50,000, or the equivalent of several neighbor-hoods. The range in uses may include a supermarket,drug store, general merchandise, or similar offering, aswell as attendant smaller retail establishments.

� Regional centers generally include retail assembliessufficient to provide a full range of retail goods andservices. They may range in size from 400,000 to over1,000,000 ft2, service areas approximating an 8 to 10-mile radius, or 20 minute drive, and populations of100,000�. They generally contain specialty offeringsand full-scale department stores, as well as supportingestablishments. Sites may range from 40 to over 100acres.

Vehicular Circulation. Transportation circulation is ex-tremely important to retail site design. Access and egresspoints should be well articulated and smoothly transitionto the adjacent public road system. Ideally, multiple accesspoints, sufficiently distanced to promote safe alternative ap-proach routes, should be secured. Traffic routes should at-tempt to separate service vehicles from customer traffic. Aseparate site entry/egress point for service traffic is idealbut may be impractical in many instances. Customer vehiclerouting should provide as near a continuous drop-off zonealong the facade of retail establishments as possible. A pe-rimeter circulation route, ring road, or street network to

access and exit the parking area can assist in reducing re-liance on travelways nearer the building and minimize thepotential conflict between through traffic and the discharg-ing of passengers or loading of merchandise. In more con-ventional retail arrangements, depending on the depth ofthe parking bays and the size of the retail center, interme-diate travelways midway between store facade and perim-eter boundaries can assist high traffic volumes in navigatingparking areas and assist overall traffic flow.

Service traffic should be directed to separate loading ar-eas and service docks. Normally this occurs to the rear ofthe retail stores, where it can be appropriately screened andrefuse containers can be shielded from public view. Loadingbay approaches and service drive design should conform toappropriate geometrics for the size and number of vehiclesnecessary to serve the development program adequately.Entry drives should be of sufficient length for vehicles toenter the site adequately prior to contemplating major turnmovements. Exists should provide sufficient stacking spaceto accommodate safe transitions into adjacent roadways.Parking. The minimum number of parking spaces re-quired to support retail activity is normally specified in thezoning ordinance, as is the required number of loadingspaces. Criteria are usually expressed as a ratio of parkingspaces to the square footage of the development program.The standards may vary depending on the service charac-teristics of the retail establishment. More spaces may berequired for enterprises with higher customer occupancy,such as restaurants, than for stores with more extensivedisplay and stock storage space, such as a furniture store.The required number of parking spaces is normally betweenfour and six spaces per 1000 ft2 of gross leasable area. Thelocal zoning ordinance should be consulted for specificstandards. Requirements for certain retail uses may requireprovision of additional spaces based on the number of em-ployees or, in the case of restaurants and theaters, on seat-ing capacity.

Although freestanding and smaller centers may accom-modate parking stalls parallel to the pedestrian walkwayimmediately in front of the retail store, larger retail centersgenerally preclude parking from the vehicular drop-off andpedestrian approach zone. In these larger retail centers, theparking area normally begins beyond the frontage servicedrive and drop-off aisle. While the configuration of the par-cel may warrant a different arrangement, parking aisles aregenerally positioned to run perpendicular to the store fa-cade. This arrangement promotes ease and safety in pedes-trian movements from their parked vehicles to the storeentries.

Retail parking normally locates the major parking areabetween the retail establishment and the major frontageroad. In larger multisided centers, such as shopping malls,parking generally encircles the center. In planned commu-nities, where stringent design standards are in place, park-ing areas may be required to be buffered from public viewor located to the rear of the retail area. Such an arrangement





minimizes the visible expanse of parking as well as pro-motes the retail building form in a forward position on thesite to assist in defining the street edge. This latter approachis key to traditional design principles, which give height-ened importance to pedestrian circulation, the use of build-ing architecture, and massing to enhance street definition.

Other ConsiderationsThe sizing of retail use for a particular site and the estab-lishment of the building floor plate should be done in con-sultation with both client and retail marketing professionals.While there are general rules of thumb associated with theprovision of retail space, rapid changes in marketing prac-tices and the unique circumstances associated with manyindividual retail establishments often prompt a tailored re-sponse that may vary from the norm. As a foundation, how-ever, several general planning guidelines are appropriate forconceptual retail site planning.

� Single-story retail programs generally result in aneffective floor area ratio of 0.18 to 0.25, depending onthe configuration of the parcel and unique site condi-tions. Multilevel malls with structured parking can re-sult in a floor area ratio exceeding 0.5.

� Conventional retail parking requirements of 5�per 1000 ft2 of building area generally entail a parkingarea approximately 2 to 2.5 times the gross area of thebuilding floor plate.

� Individual store depths generally range from 40 to150 ft, while widths may approximate 20 to 150� ft.Often the ability to partition individual tenant space isdependent on the method of construction and dimen-sions imposed by modular structural components. Theclear span between such modular supports is often re-ferred to as a building bay.

� Mall widths generally approximate 30 to 40 ftalong pedestrian corridors. The distance may increaseto 60 or more ft at intersecting corridors, or where fea-ture courts or common areas are introduced along thepedestrian spines.

� In enclosed malls, 15 to 20% of the total grossleasable area may be included in common areas suchas corridors, courts, and common mall area.

� Seven hundred ft is a reasonable walking distancebetween major retail anchors in an indoor mall. Fourhundred ft is a maximum desirable distance fromparking areas to retail entries.

� Large center retail layout is dependent on the num-ber and positioning of anchor stores. Anchors are nor-mally located at the building end or buildingintersections to provide each establishment with multi-ple facades and entrances for maximum building expo-sure and accessibility. In smaller single anchor centers,

the anchor should command a fairly central and visiblelocation, with smaller stores flanking each side. Thisarrangement assists in promoting market identity,places the larger user central to the field of parking,and positions the smaller establishments to benefitfrom the pedestrian circulation generated by the largerstore. In multiple-anchor malls or centers, the expansebetween the major stores is most valued.

� Large retail centers may reasonably support a mul-tilevel building program. In large retail centers, the in-ternal vertical circulation within multilevel anchorstores augments core mall escalators and elevators indirecting pedestrian movements to smaller stores onupper levels. Smaller neighborhood and communitycenters, dependent on ease of access and short dura-tion of visit, seldom include second story retail space.If land costs or unique market circumstances warrant asecond level, it is often occupied by office or service-related uses.

� In a large mall, a major anchor generally exceeds100,000 ft2 of gross leasable area. In neighborhood orcommunity centers, the principal food market or drugstore anchor tenant may range from 25,000 to 50,000ft2.

� Design principles for power centers or big boxusers generally conform to those for comparably organ-ized retail centers, be they standalone, strip, center, ormall arrangement. The size of the individual establish-ments, ranging from 40,000 to 100,000 ft2 and up,however, requires additional attention to potential ve-hicular and pedestrian circulation conflicts and the sizeof the parking field.

OFFICE USES: OVERVIEWSuburban jurisdictions have experienced a tremendousamount of office development over the last several decades.The scale of this activity has evolved from tacit provisionof small- scale office and administrative space serving lo-cally based municipal, medical, and professional services toincreasing accommodation of a major share of the employ-ment base of metropolitan areas. The type, scale, location,and arrangement of these facilities vary considerably. Theymay house single or multiple tenants and may be occupant-owned or leased. Construction may be prompted by thespecific program requirements of the occupant or be initi-ated on a speculative basis in response to existing or antic-ipated market demand.

In office development, zoning regulations most fre-quently focus on building bulk and site characteristics. Spe-cific controls generally include criteria detailing acceptablelimits for building site coverage, floor area ratios, buildingheight, and impervious cover allocations. Typically, mini-mum standards include provisions for parking and loading,building setbacks and yard requirements, lot size, and open





space provisions. Additional criteria may refine the qualityof the open space in specifying the extent to which it mustbe landscaped to qualify as landscaped open space or greenspace. These controls vary according to the intensity andcharacter of existing development within the community.Controls may be less stringent in more densely developedareas surrounded by compatible land uses.

Four office types or configurations are commonly foundin suburban locations: the freestanding office building, theoffice park, the garden office complex, and the townhouseoffice.

FreestandingFreestanding office buildings generally include a self-contained building on an individually recorded lot or par-cel. The building may contain single or multiple users ortenants. Space may be rented or owned by the tenant ortenants. Its occupancy of a separate recorded parcel or lotand need to singularly satisfy appropriate zoning criteria isperhaps the only generalization that may be made of thefree standing office structures. They can range from multi-floor multitenant structures with relatively high floor arearatios and heavy reliance on structured parking to smallsingle-tenant buildings serviced entirely by surface parking.

The location and context of the surrounding land usefactors heavily into the nature and execution of site designfor office buildings. A more urban siting, with higher landcosts, may confine the size of the building footprint andprompt a taller structure to secure the desired square foot-age. Such buildings may demand stronger street presenceto satisfy pedestrian access, increased reliance on structuredor below-grade parking, more intensive landscape devel-opment associated with modest residual open space, andgreater restrictions on the number and location of accesspoints.

Buildings in less urban locations benefit from lower landcosts and may result in larger building floor plates, lowerbuilding height, and more expansive site improvements, in-cluding reliance on surface parking. Building siting may ormay not demand a strong street presence. Institutional andcorporate clients may prefer a more secluded setting inwhich the building is buffered from surrounding uses forpurposes of privacy or security.

Office ParkThe office park requires coordination and control of a prop-erty assembly suitable for multiple office buildings and sup-port services. Not unlike its residential counterpart, theplanned community, the office park seeks to locate individ-ual freestanding office structures in a setting enhanced byopen space and landscape amenities. In addition to in-placejurisdictional controls, supplemental guidelines and cove-nants generally ensure that all development within the parkwill meet certain predetermined standards. The internalstreet system and infrastructure are normally planned anddeveloped by a single entity. This results in the availability

of sites suitable for sale for individual building construction.The availability of appropriately zoned office acreage within-place infrastructure is attractive to prospective owners ortenants who may not have the time, resources, or inclina-tion to subject themselves to time-consuming front-end re-quirements necessary to transform raw land for officedevelopment. The proximity of similar and related usescoupled with the shared infrastructure and amenity pack-ages, which may not be economical for any single user, areinducements for location within a well-planned and exe-cuted office park. Shared infrastructure elements mayinclude both on- and off-site utility and roadway improve-ments as well as on-site amenities. Amenity provisions canrange from extensive woodland preservation areas and wa-ter features to common recreation, athletic, and social fa-cilities. Depending on the location and scale of the park,hotel, select retail, and day care facilities may also be in-cluded. Figure 12.24 presents an office park parcel plan.

Site development in office park design, as with any com-plex multiuse building program, requires careful consider-ation of existing site features, criteria imposed by both localjurisdictional controls, prospective tenant requirements,and sound engineering and design practices. Site systems,including vehicular and pedestrian circulation, must be de-veloped to balance the overall needs of the park with thoseof individual building sites. Parcelization plans require di-mensional accuracy and flexibility in ensuring sales andmarketing. The likelihood of surface, structured, or below-grade parking has bearing on the relative development in-tensity that may be anticipated on any single site within thepark, as well as the aggregate development potential for theoverall facility.

Garden OfficeThe garden office generally provides for multiple tenanciesin a low-rise assembly of buildings. It is particularly attrac-tive to professionals and service-oriented businesses thatbenefit from proximity to surrounding residential areas. Itsscale is generally conducive to locations near residential de-velopment, and the architectural style and scale may closelyresemble garden-style multifamily residential construction.Ranging from one to three stories, the tenant space is nor-mally divided horizontally by floor, with individual entryoften open to common stairwells. Multilevel structures maybe equipped with elevators. Buildings may be arranged lin-early with common parking areas to the front, or clusteredaround parking areas or pedestrian courts. Where the ter-rain permits, entry may be gained at different levels of thebuilding, providing the additional benefit and convenienceof having associated parking at the same level as tenantspace.

Townhouse OfficeLow-rise office space compartmentalized vertically may beclassified as townhouse office. Similar to its residentialcounterpart, each unit is organized to access directly to the





F I G U R E 1 2 . 2 4 Example: office park parcel plan. (Photo by Larry Olsen)

exterior at grade level. The individual units may be single-story or multiple levels. While normally a single tenant oc-cupies each unit, smaller businesses may occupy separatefloors of the same unit.

Townhouse office, like garden office, benefits from ascale that is conducive to a location near residential areas.Its tenant profile focuses heavily on occupations and pro-fessional services that seek that proximity. Typical layoutsvary from linear to cluster patterns, and topography mayfacilitate use of the underside of the unit to accommodatea separate tenancy.

Office Design PrinciplesAs with retail design, there are a few governing principlesthat are appropriate for office parcel layout and design.Foremost in this checklist are the specific requirements ofthe local jurisdiction. Zoning conditions may encompassbuilding setbacks, buffering and screening requirements,

and minimum parking counts, as well as govern the height,bulk, and size of the building program. Municipal controlsmay reflect pro forma criteria attributable to the parcel zon-ing or tailored to the unique circumstances of a site relativeto surrounding land uses and/or on-site characteristics.

Design of these elements requires attention to the detailsof site organization and function. Considerations generallyinclude:

� Sensitivity in orchestrating an appropriate externalimage given potential roadway and land use adjacen-cies

� Site and building access that is legible and avoidscongestion

� Efficient floor configurations that are conducive toleasing and occupancy requirements

� Sufficient parking given tenant requirements





� Parking that is convenient to both occupants andvisitors

� Site development and amenity provisions that aretailored to meet the requirements of developer andtenant

� Service and loading design that avoids conflict withnormal building operations and is adequately screenedfrom occupant and community view

The range of land use intensity attributable to conven-tional office use can vary considerably. Floor area ratios inexcess of 1.0 are not uncommon in proximity to suburbanmixed-use centers. However, suburban office intensities forconventional freestanding buildings more commonly rangefrom a 0.25 to a 0.4 FAR, which results in building heightsof one to four stories. The 0.4 FAR is normally consideredthe threshold at which an office building may be surfaceparked while maintaining reasonable distances between thebuilding and outer perimeter parking areas. An FAR greaterthan 0.4 normally requires significant reliance on subsur-face or parking structures.

Although traditional parking ratios for office use aver-ages four spaces per 1000 ft2 of net leasable space, the re-quirement may be lessened at locations close to publictransportation or mass transit. In some circumstances, park-ing demands may be lessened if a disproportionate amountof building space is to be utilized for operations that arenot employee-dependent. On the other extreme, tenancythat requires high visitor turnover, such as medical officeuses, may necessitate higher parking ratios. Similarly, antic-ipated building occupancy by tenants employing smallerper employee work areas, such as telecommunication callcenters or 24-hour operations with overlapping work shifts,may require parking that exceeds conventional office cri-teria.

INDUSTRIALLocal development standards governing industrial activityhave often augmented traditional zoning criteria that estab-lish controls on maximum land use intensity, minimum lotsize, setbacks, and building bulk and height, with specificperformance standards that serve to categorize not only per-mitted types of industrial activities, but minimum standardsassociated with their operation. Performance criteria maybe tied to standards governing air pollution control; fire andexplosion; radiation hazard; electromagnetic radiation andinterference; liquid and solid waste discharge; and noise,vibrations, and light source considerations, among others.

The nature, extent, and complexion of industrial landuse has changed dramatically in the last several decades.The expansive single-purpose facilities focusing on rawmineral extraction, product manufacturing, and assemblyhave been overshadowed by the provision of more flexiblespace that focuses on product distribution, research, andservice industries. This transition has had a profound im-pact on the location requirements of industrial uses and the

physical characteristics of industrial facilities. It has alsolessened community resistance to a genre of uses that donot pose the level of incompatibility historically associatedwith industrial activity, including potential air pollutants,hazardous waste byproducts, acoustical and vibration im-pacts, and heightened fire and safety considerations.

While heavy industrial, extractive mineral, and expan-sive processing facilities can be found in suburban loca-tions, escalating land values combined with newtechnologies have often prompted many of these types ofindustries to relocate to areas where land cost and laborsupply and use controls are more conducive to theiroperations. In their stead, activities focusing on researchand development, smaller-scale electronic assembly, dataprocessing, telecommunications, product distribution, andwarehousing have become more significant industrial com-ponents of many metropolitan areas. The noxious charac-teristics of traditional industrial activity located proximateto railroad lines have given way to expansive industrial andtechnology parks whose locations are governed more byconvenient access to interstate highways, airports, and pop-ulation centers.

Building programs associated with industrial activitygenerally rely on a strong building-to-ground relationship.This is in keeping with their dependence on truck transportas a principal means of product delivery and assembly op-erations, which rely on horizontal line arrangements andon-grade structural conditions to support machinery andexpansive storage and warehousing requirements.

Sensitivity to the diversity in industrial uses of both his-toric and contemporary facility types has prompted mostjurisdictions to adapt their zoning ordinance to provide var-ying standards for select classes of industrial activity. Clas-sifications normally differentiated among light, medium,and heavy industrial uses. The gradation was strongly re-lated to the potential level of land use incompatibility an-ticipated between the subject industrial operations andadjacent land uses. In recent years, finer distinctions havebeen made to accommodate the less onerous industrialcharacteristics associated with research and development(R&D) activities. In R&D parks and similar institutionalenvironments promoting scientific research and product de-velopment, training and offices manufacturing or productassembly may be either nonexistent or only a diminutivepart of the overall facility operation. The potential land useconflicts and levels of incompatibility characteristic of tra-ditional industrial activity may be negligible.

Building programs that reflect some of the more typicalindustrial arrangements found in the suburban market areillustrated below.

Heavy IndustryPrecedent activity, proximity to raw materials, natural re-sources, power sources, and location at major transporta-tion hubs and population centers are several factors thatprompt the need for heavy industrial activity in otherwiseurban and suburban markets. Generally, these activities fos-





ter a litany of potential use conflicts. Zoning criteria nor-mally focus on minimum dimensional standards andperformance criteria to reduce or contain the impacts ofsuch uses. Facilities may include intense manufacturing op-erations; heavy equipment, construction, and fuel yards;mining and quarrying; major transportation terminals; andother equivalent concentrations of potential noxious uses.Heavy reliance on truck transport favors industrial locationswith reasonably convenient access to major arterial or col-lector roads or, in the case of interstate trade, major free-ways and highways. Reliance on rail and water accesscontinues to be important to certain types of industrial ac-tivity.

Heavy industrial uses tend to be land-consumptive interms of building program or exterior space requirementsfor vehicular movement and storage. Floor area ratios of0.5 to 1.0 with surface improvements as high as 80 to 90%of the usable site area are common. Site design issues focuson adequacy of site entry and egress; internal site circula-tion with regard to potential separation of visitor, employee,service and facility operating needs; and screening of exte-rior storage and loading areas from external site views.

Medium Intensity and General Industrial UseProduct fabrication and assembly operations, storage, andsimilar industrial operations in suburban locations tend tobe categorized as light manufacturing. They offer reducedlevels of noise, smoke, glare, and other environmental pol-lutants normally associated with the more intense or heavyindustrial activity. Development considerations and site de-sign issues do not differ substantially from those previouslycited. Characteristics associated with a smaller scale of op-eration or activity that has a relatively less invasive impacton surrounding land uses often accommodate mitigation ofconcerns within the confines of the site

Light IndustrialThe light industrial classification affords more lenient stan-dards, given the more compatible nature of permitted uses.Uses include activities considered least obtrusive and op-erating under high performance standards relative to off-site impacts. Floor area ratios may be less expansive,ranging from 0.4 to 0.5, and operations including storagemay be required to be entirely under roof.

Special Industrial Use PatternsContemporary development patterns, evolution in buildingtechnology, and opportunities or requirements for the con-tainment of noxious impacts have fostered a radical alter-ation in industrial prototypes over the last several decades.This has resulted in refinements in standard land use con-trols, which are sensitive to trends in the aggregation of

compatible industrial activities in planned industrial parks.The emergence of zoned industrial districts qualified as in-stitutional, research, technology, warehouse, and distribu-tion centers reflects unique sets of operating requirements,an affinity for like-kind uses to collocate, and market-drivenpressure to elevate the site aesthetics of select industrialland use activities.

Local public controls may afford opportunities for thecreation of an industrial district that caters to uses that candemonstrate compatibility with surrounding land activities.Minimum land assembly, larger minimum lot requirements,increased setback, screening and buffer requirements, in-creased landscape and open space standards, reduction inallowable building profiles, more restrictive building bulkcriteria, and allowable land use intensities as low as 0.25FAR assist in ensuring reduced visual impact on surround-ing areas for uses that can demonstrate no adverse off-siteimpacts. Positioning more compatible activities at perimeterlocations often assists in creating an overall planned indus-trial development that affords considerable variety in ten-ancy and use opportunities. A typical industrial park ispresented in Figure 12.25.

Industrial /Office/Retail Hybrid Building FormsOne of the more notable and popular building forms thathas emerged in suburban development markets is the flex-tech or office showroom prototype. The overall buildingshell is designed to allow the compartmentalization of sep-arate units, depending on the spatial needs of individualtenants. Generally, unit or bay sizes are tied to the modulardimensions of the building structure (the roof span betweenvertical support elements). Common modules range from20 to 45 ft. As in construction techniques employed inconventional retail centers, the overall length of the build-ing may be divided by interior walls, providing each oc-cupant an exterior exposure on both the front and serviceside of the building. The front exposure is generally devotedto pedestrian access and proximate parking. Limited retailsales, showroom, or administrative offices may be locatedat the front of the tenant bay. The utility or service side ofthe bay is accessed from a vehicular service drive. Servicedrive pavement dimensions are sized relative to the type ofservice vehicle required for the targeted tenant group. Whilesmaller delivery trucks can be accommodated in as little as45 ft, docking and circulation widths generally range from85 ft to 130 ft for larger vehicles. Individual or shared load-ing docks or service doors generally extend along the ser-vice facade proximate to interior bay storage, fabrication, orassembly operations.

While buildings are normally single-story on slab con-struction, full or partial second stories (mezzanine levels)may be incorporated into the building. Upper levels arecommonly devoted to administrative uses and often are lim-ited to the font module of the building, leaving the areasabove the utility portion or rear of the building with a





F I G U R E 1 2 . 2 5 Example of industrial park; Renaissance Park, Fairfax, Virginia, is an example of a hybrid industrial park with (a) hotel locatedon a major highway frontage, (b) traditional office / research and development building types with separate parking areas and limited loading facilities atmore visible locations, and (c) flex industrial building types with visitor / employee parking along the building frontage and a continuous service / loadingarea running the rear building length. (Courtesy of Air Survey Corp.)

higher ground-to-ceiling height, normally 14 to 20 ft. Thetype and flexible size of tenant space, up-scale facade treat-ments, and overall site finish associated with facilities of thistype are attractive to a diverse range of tenants, which mayinclude such uses as bulk warehouse, industrial /office, lightmanufacturing, office/showroom, research and develop-ment, and retail service centers.

Lot coverage and floor area ratios vary according to localregulations and size and bulk requirements of principal usergroups. Generally, larger users command higher coverageand FAR capacity owing to the magnitude of desired floorplate and associated reduction in employee and customerparking needs. A reasonable range in smaller flex-tech andoffice showroom combinations may be between 0.24 and0.35 FAR. Figures 12.26 and Figure 12.27, respectively, il-

lustrate the flex-tech building and portion of a flex-techpark.

CONCLUSIONResponse to contemporary development trends, particularlyin the suburban context, has fostered much introspectionin regard to both the quality of life and the environment.While the development of land will in all likelihood notabate, greater integration of uses internal to individual de-velopments or within the larger community context is in-creasingly evident in our built environment.

New market opportunities and community planning in-itiatives that seek to better direct and control the location,content, and quantity of development have fostered this at-titude.





F I G U R E 1 2 . 2 6 Example of flex-tech building.

Numerous factors have occasioned a renewed look atdevelopment market opportunities and in turn develop-ment composition and project content. Increasing landcosts have promoted an increase in development densities.The level of vehicular congestion has prompted more de-liberate evaluation of development opportunities proximateto mass transit facilities or in closer proximity to supportiveland uses, which might minimize reliance on the automo-bile or shorten travel time. Increased popularity in a greatervariety of leisure activities, coupled with shifting demo-graphics toward smaller families, empty nesters, and single-occupant households, prompts evaluation of requisite yardrequirements, the venue of project amenity provisions, andproximity to existing and proposed community institutionaland cultural offerings.

Public initiatives, in attempting to come to terms withthe public infrastructure required to support future devel-opment activity, have similarly focused on efforts to mitigate

the current dependence on the automobile as the principalmode of transportation. Efforts to promote mass transit,concentrate development density near existing and plannedtransportation corridors, and integrate a variety of residen-tial, retail, and employment uses with greater reliance onpedestrian travel all attest to the prospect for less insular,more integrated land development patterns.

Emerging trends on the content and context of devel-opment patterns and principles include:

� A greater focus on the integration of uses, as mightbe exhibited in a reduction in distances between devel-opment types, or vertical integration, as with first floorretail and upper level office or residential uses

� A finer grain in mixing uses, from the standpointof an increased variety of residential types given themarket diversity of residents, and greater integrationwith nearby retail and employment activities





F I G U R E 1 2 . 2 7 Example of flex-tech park.

� A renewed focus on the connectivity within andbetween developments in ensuring adequate and alter-native means of vehicular movement as well as greaterattention to pedestrian opportunities

� A reassessment of the location of open space withrecognition of its role in place making and elevating itbeyond the unusable or leftover ground within a devel-opment

� Increased attention to building placement, massing,and scale as tools in defining space, directing views,and encouraging diversity in the pedestrian experience

� A reassessment of the nature, magnitude, andplacement of parking in terms of (1) potential for jointuse and parking reductions owing to use adjacencies,(2) increased reliance on integral parking or parkingstructures in response to increased land cost, and (3)potential relegation of parking from forefront to rearyard as buildings move street-side

� Continued evaluation of the hierarchy and configu-ration of street networks, recognizing the need for safeand efficient vehicular movements as well as enhancedpedestrian opportunity and experience

ADDITIONAL READINGSDe Chiara, Joseph, and Lee E. Koppelman, Site Planning Stan-dards, McGraw-Hill, New York, 1978.

Engstrom, Robert, and Marc Putman, Planning and Design ofTownhomes and Condominiums, Urban Land Institute, Washing-ton, D.C., 1979.

Jensen, David R. /HOH Associates, Zero Lot Line Housing, UrbanLand Institute, Washington, D.C., 1981.

Lynch, Kevin, and Gary Hack, Site Planning, MIT Press, Cam-bridge, Mass., 1984.

Maitland, Barry, The New Architecture of the Retail Mall, Van Nos-trand Reinhold, New York, 1990.

National Association of Home Builders (NAHB), Cost EffectiveSite Planning: Single Family Development, NAHB, Washington,D.C., 1982.





National Association of Home Builders (NAHB), Land Develop-ment 2, NAHB, Washington, D.C., 1981.

Rathbun, Robert Davis, ed., Shopping Centers and Malls 3, RetailReporting Corporation, New York, 1990.

Tomioka, Seishiro, and Ellen Miller Tomioka, Planned Unit Devel-opments: Design and Regional Impact, John Wiley & Sons, NewYork, 1984.

Untermann, Richard, and Robert Small, Site Planning for ClusterHousing, Van Nostrand Reinhold, New York, 1977.

Urban Land Institute (ULI), The Community Builders Handbook,ULI, Washington, D.C., 1968.

Urban Land Institute (ULI), Industrial Development Handbook,ULI, Washington, D.C., 1975.

Urban Land Institute (ULI), Office Development Handbook, ULI,Washington, D.C., 1982.

Urban Land Institute (ULI), Project Infrastructure DevelopmentHandbook, ULI, Washington, D.C., 1989.

Urban Land Institute (ULI), Residential Development Handbook,ULI, Washington, D.C., 1990.

Urban Land Institute (ULI), Shopping Center Development Hand-book, ULI, Washington, D.C., 1977.




Conceptual Design

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