Historic View (c. 1910) of the Prospect Park Subdivision, Pasadena, California, shows how pioneers in California's Arts and Crafts movement transformed the dry and barren site along the Arroyo Seco into one of the region's earliest and most attractive planned suburbs. Historic photographs shape our understanding of past time and place. They enable surveyors to trace the evolution of a particular historic neighborhood, as well as visualize the ways that demographic trends, modes of transportation, and changing ideas about subdivision planning, house design, and gardening defined distinct stages of suburban growth and, in many places, have contributed to regional character. (Photo courtesy Pasadena Historical Society)

Identification activities are designed to recognize properties associated with historic patterns of suburbanization and to gather information to determine the National Register eligibility of historic subdivisions and neighborhoods. The identification process calls for the development of a historic context at the local or metropolitan level and the documentation of associated properties using historical research methods and field survey techniques.

Contextual information on local patterns of suburbanization can guide survey work by providing a link between historic events and the physical evolution of communities. In turn, survey information expands the understanding of local patterns, adding to the local context information about the location, character, and condition of representative subdivisions and neighborhoods.

Information previously gathered through the statewide comprehensive survey and other historic contexts (local or state) should be supplemented by new research and field surveys that extend not only the geographical area covered by earlier surveys but also the chronological period considered historic. Keep in mind that the findings of earlier surveys and context statements may need to be reevaluated and updated according to new contextual information about historic patterns of suburbanization.

DEVELOPING A LOCAL HISTORIC CONTEXT

The nationwide context, "The Suburbanization of Metropolitan Areas of the United States, 1830 to 1960," can be applied to the study of suburbanization on a local or metropolitan scale. In addition, a number of states have developed historic contexts and multiple property submissions that address various aspects of suburbanization (See Recommended Reading for a list of associated multiple property listings). Through historical research and field surveys, documentation is gathered to form a written statement of historic context, a master list of residential subdivisions, and one or a series of maps charting suburban growth of an entire metropolitan area or a single or small group of local communities within it.

Conducting Historical Research:

Initially historical research is directed at gathering general information about metropolitan or local patterns of development, most importantly 1) demographic trends, 2) transportation systems and routes, 3) patterns of land development and subdivision design, and 4) trends in suburban housing and landscape design. Later, additional research in conjunction with field surveys may examine the history of specific neighborhoods.

Photograph (c. 1898) of Shaw Avenue Place, one of St. Louis's "private places." Historic photographs documenting the design, construction and daily life of residential suburbs exist in many local historical collections. (Photo courtesy Missouri Botanical Garden Archives)

Determining Geographical Scale and Chronological Periods:

Demographic trends can help document the approximate growth and extent of local suburbanization and establish the periods of development associated with particular methods of transportation. From this data, predictions can be made about the types of suburbs likely to exist. For example, metropolitan areas in the eastern United States, which experienced rapid growth due to industrialization during the nineteenth century, likely contain the full spectrum of suburban properties. Those in the Midwest, which began to experience significant growth in the 1880s, would probably include streetcar, early automobile, and freeway suburbs; and western cities, which didn't expand until the twentieth century, can be expected to contain early automobile and postwar or freeway suburbs.

Using the date of legal incorporation for the central city as a starting point, researchers can make an initial estimate of the period of historic suburbanization by plotting a graph that compares the population growth of the central city to that of adjacent counties (or smaller jurisdictions if the data is available for them) in ten-year intervals through 1960, using data from the U.S. Census. Such a graph will indicate not only when and where suburbanization likely occurred but also the extent to which local patterns correspond to the broad chronological periods identified in the national context.

The metropolitan area is the most appropriate scale for studying patterns of suburbanization and establishing a local historic context. However, limitations of time and funding, as well as the difficulty of coordinating efforts among multiple governing jurisdictions (sometimes located in several states), may make this approach impractical and make it necessary to establish a context for a single or small group of localities within the larger metropolitan area. In such cases, sufficient information should be gathered about metropolitan trends to explain how the history and development of the local community reflected patterns of suburbanization that shaped the metropolitan area as a whole.

For research and survey purposes, a set of historic chronological periods should be defined that correspond to local events and stages of suburbanization. This can be done by dividing the history of local historic development into chronological periods that generally correspond to those outlined in the transportation section of this bulletin, and assigning each period a set of dates based on local events, such as the introduction of the streetcar or the subdivision of the first automobile suburb. By comparing local trends in transportation, subdivision design, and housing design and construction to general national trends, researchers can make predictions about the types of subdivisions and suburban housing likely to be present in the local study area, as well as identify distinctive regional patterns.

Suburbanization has been an ongoing and continuous process in many communities. For this reason, it is important to use specific events and patterns in local history to define the beginning and closing dates for the overall "historic" period, as well as dates for chronologically-based property types. Approximate dates set at the beginning of the study can be revised later after research and field surveys have been completed to ensure accuracy. Actual events rather than an arbitrary 40- or 50-year cutoff should be used when examining patterns of suburbanization after World War II.

Compiling Data from Historic Maps and Plats:

Historic maps are particularly useful for studying patterns of suburbanization because they graphically depict the relationship between transportation corridors and residential development. Those from the mid-1880s are particularly helpful in locating railroad suburbs, whereas maps dating from 1900 to 1920 are good indicators of the expansion of streetcar suburbs. Maps from the late 1930s to mid-1940s help trace the development associated with the early automobile period, and those from the late 1950s will help trace the massive suburbanization spurred by the expansion of arterial roads and freeways in the postwar period.

Because transportation methods and routes have historically defined the limits of suburbanization, a sequence of historic maps indicating transportation routes should be assembled. The maps should represent dates far enough apart that they capture significant changes in the overall landscape. These maps can be compared to trace the relationship between transportation and subdivision development and determine the dates when major episodes of suburbanization occurred locally. Because little physical evidence of streetcar routes remains today, maps showing these routes are a key resource for identifying and verifying the presence of streetcar suburbs.

Publicly recorded plats provide an abundance of information about local patterns of subdivision design and real estate practices. Designed by William H. Schuchardt in 1922 as an experimental housing cooperative of detached and semi-detached homes to ease Milwaukee's housing shortage, the Garden Homes Subdivision was replatted with subdivided lots in 1934 so that homes could be sold to tenants and stockholders when the cooperative was dissolved. (Historic plat by H. L. Lockhart, courtesy Wisconsin State Historical Society)

1) the date when a subdivision was platted;
2) original legal jurisdiction and boundaries of the subdivision;
3) name of the land development company or real estate developer responsible for subdividing the land;
4) original layout of the streets, utilities, and house lots; and
5) adjoining streets and arterials.

The requirements for recording plats vary from locality to locality. Researchers should make inquiries about local practices for both recording subdivision plats and for maintaining them as archival records. Plat books may be on file at the local courthouse or planning office. The search for historic plats may also involve contacting distant repositories, such as State historical societies or specialized archives housing the records of developers, site planners, or landscape architects. Research of fire insurance maps, recorded deeds, and written notices by land development companies may provide similar and additional information about community planning.

Mapping the Study Area

Information from the historic maps, plats, and other records can be used to prepare a map or series of maps charting the outward expansion of suburban development. Maps should indicate the name, date and location of railroad stations, streetcar routes, major arterial streets, parkways and boulevards, and highways, as well as principal land subdivisions. Reference copies should be prepared for field surveys so that the presence of resources can be verified and observations recorded about condition, boundaries, and potential eligible resources.

The best approach for graphically depicting the relationship between transportation and suburbanization is to begin with a current geographical map of the study area as a base map and create a series of overlays or period maps, each representing an important chronological period and showing the relationship of transportation facilities and subdivision development during that period. Such maps not only illustrate important aspects of the historic context, they also can be used to document multiple property listings, survey findings, and the evolution of large residential districts. Geographical Information Systems (GIs), Global Positioning Systems (GPS), and a number of softwares for mapping now make it possible to efficiently organize digitized information about residential development in the form of maps and comparative graphs.

Preparing a Master List of Residential Subdivisions

General street maps, local plats and planning documents, fire insurance maps, and transportation maps usually provide sufficient information to compile a master list of subdivisions for each chronological period. For survey purposes, the list should be cross-referenced to the field map and should provide the historic name, current name, dates of platting, as well as the names of real estate developers and designers, if known. Based on survey findings and additional research, the list can be further annotated to describe key characteristics such as size, street design, block size, number of lots, types of original improvements, periods of construction, house types, and condition. Many communities are now making tax assessment and planning information available online or on CD-ROM; such a readily available source of digitized data not only provides a wealth of information about residential subdivisions and local housing types, but can be used in a variety of ways, including maps and comparative graphs.

  Developing a Statement of Context:

Local contexts typically identify the general types of single and multiple family housing associated with particular socioeconomic groups, local industries, and stages of suburbanization. Three-deckers, also called triple-deckers, making up the Houghton Street Historic District (top) in Worcester, Massachusetts, represent a housing type common to the industrial cities of the Northeast where immigrants and others viewed renting out "flats" as a means of affording a home of their own. The Georgian Revival steel house (bottom) with garage located at 129 South Ridge is one of 22 homes constructed between 1932 and 1941 in Troy, Ohio, by the Troy-based Hobart Welded Steel House Company to demonstrate that arc-welding methods could be used to produce high quality prefabricated housing at a low cost. (Photo by Michael Steinitz, courtesy Massachusetts Historical Commission; photo by Diana Cornelisse, courtesy Ohio Historic Preservation Office)

 The statement should include a brief summary of the history of the metropolitan region and local community being studied and an explanation of the factors-geographical, legislative, and economic-that have influenced the growth and suburbanization of the region. In addition, the statement should explain the jurisdictional boundaries within the metropolitan region and identify the governing bodies historically responsible for local planning and development in the area being studied. It should contain dates, the proper names of influential individuals and organizations, and references to representative historic subdivisions and neighborhoods associated with the context.

Local contexts on suburbanization typically include information about the following:

•Transportation trends, including the location of railroad stations, streetcar routes, major arterial streets, parkways and boulevards, and express highways (freeways).
• Local events that reflect national trends in transportation, industry, commerce, and government.
• Local economic, demographic, and other factors that historically influenced the location and expansion of residential suburbs (e.g. rise of aerospace industry).
• Representative types of residential subdivisions and neighborhoods believed or known to exist in the study area, including the name, dates, and general characteristics of important examples.
• General types of single and multiple family housing that characterize the area's residential development, including their association with particular income levels, socioeconomic groups, industries, or local events.
• History of local or regional planning efforts, including the introduction of zoning ordinances, comprehensive planning, and subdivision regulations, which historically influenced patterns of suburbanization.
• Local practices concerning mapping, recording of subdivision plats, aerial surveys, and issuance of building permits, noting any particular records that are strong indicators of suburban growth and development.
• The ways that local patterns of suburbanization reflected changing views and attitudes about family, home, and the social roles of men and women.
• The ways local patterns of housing and subdivision design reflected national trends in architecture, landscape architecture, and community planning.  

Page from architect James H. McGill's Architectural Advertiser (1879) showing the Le Droit Park residence designed for Mr. Scott of Washington, D.C. Promotional brochures and advertisements are good sources of historical information and may be found in the collections of local libraries, historical societies, and community organizations. (Illustration courtesy District of Columbia State Historic Preservation Office)

•Establishment and activities of local chapters of the National Association of Real Estate Boards, National Association of Home Builders, American Institute of Architects, American Society of Landscape Architects, American Civic Association, American Institute of City Planners, Better Homes of America, Inc., and Small House Architect's Service Bureau, including the names of members who were influential in shaping local patterns of suburbanization.
• Principal subdividers, home builders, real estate developers, and lending institutions, including a description of the types of residential and other development with which they were associated, and any distinctive local practices, such as the use of deed restrictions or development of neighborhood shopping centers.
• Principal site planners, architects, and landscape architects known for residential design in the local community or metropolitan area, including examples of their work, the housing types or characteristics of design for which they were known, and the identity of subdividers and builders with whom they routinely worked.
• Biographical sketches of 1) real estate developers known to have had substantial impact on local patterns of suburbanization, and 2) architects, landscape architects, and engineers who influenced the design and character of residential suburbs in the metropolitan area or local community, by introducing innovations in design, achieving work of high artistic quality, or establishing local traditions of design and construction.

SURVEYING HISTORIC RESIDENTIAL SUBURBS

Most historic resource surveys are conducted in two phases once background research has been completed. During the first, called the reconnaissance survey, the study area is surveyed to identify subdivisions and other property types illustrating local patterns of suburbanization. Observations are systematically recorded about the general character and condition of numerous subdivisions and neighborhoods.

During the second phase, called the intensive-level survey, more detailed information is gathered on one or more neighborhoods and other resources believed to meet the National Register criteria. Survey at this level proceeds with the purpose of verifying significance and integrity, establishing appropriate boundaries, and gathering sufficient documentation to complete a National Register nomination.

Because of their large size and great number, residential suburbs present a challenge to preservationists and decision makers. Field survey, data analysis, and reporting methods can be greatly facilitated through the use of an electronic database that can store, sort, and report data in a number of ways. The State historic preservation office or Certified Local Government should be contacted for guidelines about data entry and retrieval systems currently being used for the statewide comprehensive survey and acceptable formats for National Register nominations.

Streetscapes of the Cameron Park Historic District, Raleigh, North Carolina, one of three large subdivisions platted c. 1910 during an extensive period of urban growth. Neighborhoods were nominated to the National Register through a survey of the city's historic residential neighborhoods, which included the development of a historic context documenting local patterns of suburbanization. These efforts resulted in a multiple property submission entitled Early Twentieth Century Raleigh Neighborhoods. Due to the extremely large study area and predominance of residential resources, surveyors systematically proceeded from the city's oldest sections to newer ones recording block faces on multiple structures forms that were later grouped together by subdivision and cross-referenced to files on selected individual properties. (Photos by Diane Filipowicz, courtesy North Carolina Department of Cultural Resources)

Field observations, as well as facts gathered from historical research, should be recorded in a systematic and uniform way. Generally this is done on inventory forms provided by the State historic preservation office. The forms selected for use should be appropriate for the level of the survey and the types of historic properties likely to be found in the survey area.

 
During a reconnaissance survey, the use of a multi-structure or historic district form may be most useful for recording preliminary information about a subdivision, neighborhood, or streetscape cluster. For intensive survey, a more detailed district form may be needed, as well as individual structure forms to document the character and condition of individual buildings or groups of buildings having common characteristics. Since survey requirements vary from State to State, surveyors should work out a plan with the State or local preservation office for making the best use of existing survey forms and deciding how additional information, such as street patterns or spatial organization, is to be collected. Some State programs use the National Register of Historic Places Registration Form (NPS 10-900) or a similar form for recording intensive-level survey data, including an inventory of contributing and noncontributing resourc-es. (161)

 Information needed to evaluate the significance of a particular residential subdivision or neighborhood depends to a large degree on the chronological period in which it developed and the historical factors that shaped it. Factors, such as the income level of prospective home owners, the relationship of subdivider and home builder, and methods of house construction, varied from period to period and frequently defined a neighborhood's physical character, as well as social history.

An oasis in the desert, Tucson's El Encanto Estates evolved from a geometrically perfect radial plan (1929) designed in the office of a California engineering firm and later laid out by field engineers on the floor of the Sonoran desert. A c. 1934 aerial photograph depicts early improvements, including the layout of streets and spacious lots, rows of evenly-spaced street trees, and a central, circular park. A sales map prepared in 1951 indicates the extent to which streets had been extended and lots further subdivided following World War II. Supplementing State survey forms, a horticultural inventory form was used to record information about the Mexican fan palms (Washingtonia robusta) and date palms (Phoenix dactylifera) lining the streets and the stately collection of giant saquaro (Carnegiea gigantea) gracing the central park. (Photo and sales map courtesy Arizona Historical Society Library/Tucson)

 
Field Reference Materials:

The master list of residential subdivisions and the composite or overlay maps prepared for the local historic context (see Developing a Statement of Context ) serve as valuable reference materials during field survey. In addition, copies of the following documents will be useful:
• current street maps, planning maps, and U.S.G.S. quadrants;
• early transportation maps, indicating streetcar routes, parkways and boulevards, and highways;
• aerial photographs (dating back as early as the 1930s in some communities);
• historic subdivision plats;
• historic photographs and illustrations; and
• fire insurance maps, such as those produced by the Sanborn Fire Insurance Company.

Field reference materials should provide a level of detail appropriate for the type of survey being conducted. For example, historic plats and current planning maps showing principal streets, location and boundaries of residential land use, and principal topographic features, are useful for reconnaissance surveys, while tax parcel maps and Sanborn maps showing the size, shape, and location of individual house lots provide detailed information useful in intensive-level surveys.

The Reconnaissance Survey:

Information gathered during the reconnaissance survey strengthens the local historic context, making it possible to identify locally significant property types and set registration requirements for National Register eligibility. The survey should result in an inventory of historic neighborhoods, subdivisions, and other resources that are potentially eligible for National Register listing. Survey results can be used to select the best approach for nominating eligible properties to the National Register and set priorities for local preservation planning.

Information collected should:

• Provide a general picture of the distribution of different kinds of subdivisions and house types in relationship to historic transportation routes.
• Verify, refine, and expand information gathered through literature and archival sources about patterns of suburbanization and the characteristics of historic suburbs in the local or metropolitan area.
• Provide enough information on the character and condition of specific neighborhoods to identify locally important property types, such as planned communities or apartment villages, and make recommendations on neighborhoods and other related resources that merit intensive-level survey and may be eligible for National Register listing.
•Provide an understanding of the factors that threaten the integrity of historic neighborhoods, and help establish a threshold for evaluating historic integrity of individual neighborhoods and determining general registration requirements.

During field work, surveyors should take special note of and record information about neighborhoods, as well as individual resources, which are likely to represent important property types and illustrate important aspects of the region's suburbanization. Such properties may include:

• residential subdivisions, or groups of contiguous subdivisions, that represent broad national trends in transportation, subdivision design, community planning, architecture, or landscape architecture;
• neighborhoods that possess historic associations with events or activities in the history of a local community or metropolitan area, or represent locally distinctive methods of construction or design characteristics;
• clusters or streetscapes having historic values, associations, or design characteristics that distinguish them from the larger subdivision of which they were originally a part;
• single homes associated with persons important in our past or distinctive for their architectural design or method of construction, or as the work of a master;
• and community centers, schools, and shopping centers within or adjacent to a residential neighborhood which are associated with important historic events or possess architectural distinction.

While the residential subdivision is the focus of survey activities, historic neighborhoods may extend beyond the boundaries of a single subdivision. Historic associations or physical characteristics linking these areas should be documented and considered in making recommendations about their collective significance or National Register eligibility. Conversely, where a historically important neighborhood no longer possesses historic integrity in its entirety, a smaller area retaining significant qualities and associations may be eligible. Individually eligible resources associated with the suburbanization context but located outside the boundaries of a potentially eligible historic district should also be identified.

Information about city planning, including the development of transportation routes, helps surveyors trace the evolution of historic suburbs and determine appropriate boundaries for historic districts. A c. 1923 aerial view depicts the infrastructure of electric streetcar lines and wide boulevards that, extending from downtown Cleveland, would spur the suburbanization of Shaker Village in coming decades. By the end of the 1920s, Moreland Circle (lower right of photo) would be transformed into Shaker Square, a commercial center and transportation hub for the rapidly growing suburb. By 1950, Shaker Village contained more than 4500 dwellings and apartment buildings in numerous subdivisions.

A map of the Shaker Village Historic District indicates historic district boundaries, a complex pattern of neighborhood streets, and the rapid transit routes and major thoroughfares that continue to serve the historic district today. (Photo courtesy Western Reserve Historical Society; map courtesy Ohio Historic Preservation Office)

Organizing an Itinerary

Organize an automobile itinerary that follows historic transportation routes as closely as possible, directing surveyors from the oldest to the newest subdivisions so they can gain a sense of the range of variation that occurred in housing types and subdivision design throughout the community's history.

Because the boundaries of historic subdivisions are often invisible in the field and may not be evident on contemporary street maps, it is a good idea to have copies of historic maps, plats, and aerial photographs, as well as the composite map or series of overlay maps prepared for the historic context. This is especially important when surveying older suburbs where housing was built in small subdivisions by a variety of builders, often following the rectilinear urban grid, and where subdivision boundaries are not necessarily signaled by changes in architectural style, housing type, or street design.

Recording Field Observations

Following the itinerary and using current and historic street maps as a guide, proceed in two stages. First, drive through as many subdivisions as possible making general notes and taking photographs. Second, for each major subdivision, neighborhood, or distinctive cluster, record field observations incorporating information gathered from maps, plats, and other field reference materials.

Surveyors should be prepared to take photographs, annotate field maps, and complete survey forms as they proceed through each subdivision. It is important to note the presence of distinctive features of architecture, landscape design, and community planning that might be attributes of historic significance and should receive further documentation during an intensive survey. This includes unusual house types, distinctive architectural types, characteristic streetscapes, evidence of professional principles of landscape design, important vernacular trends in housing or yard design, or highly distinctive site plans. Similarly, note interesting historical associations or observations on community life, such as annual traditions, the role of a citizens' association, or the presence of a community center.

One can expect to find a huge variation in the size and design of neighborhoods. Those subdivided before World War II may be relatively small in size, often consisting of little more than a single, rectilinear street with a handful of rectangular lots to either side. In these cases it may be useful to develop a system of classifying such subdivisions by attributes-such as street pattern or architectural variety-to define local patterns and establish a set of local property types, or to look for common characteristics that link subdivisions into larger historic neighborhoods.

Analyzing Survey Results:

Survey data should be incorporated into the written statement of context, and connections made between broad patterns of local suburbanization and the development of specific suburbs and neighborhoods. At this point, the master list of subdivisions can be annotated to include information about developers, builders, architects, site planners, and other designers and to note important events in social history that illustrate locally important themes or trends. Also, note the condition of specific subdivisions and the general nature of changes that each area has undergone since the end of the historic period.

Information about distinctive characteristics of site planning, housing, or landscape design should be used to define significant local patterns, to document the work of important designers, and to identify properties that should be more closely examined for significance in architecture, landscape architecture, or community planning during the intensive survey. Likewise, information about events in the neighborhood's cultural or social history should be used to identify neighborhoods associated with significant patterns of community life and social change. Survey information about condition of local residential suburbs and housing types will help establish thresholds for evaluating historic integrity in the local area.

From this synthesis, it is possible to 1) define the set of locally important property types, 2) formulate registration requirements for National Register listing, and 3) compile a list of subdivisions, neighborhoods and other properties that appear eligible for the National Register and merit intensive-level survey.

Analysis of survey data will also suggest areas of further research, appropriate research methods, and special concerns for significance or integrity. For example, observations about the range of housing types may suggest clues about the relationship of subdividers and builders, the period of development, sources of design, and use of restrictive deeds, which can be substantiated through further research conducted during the intensive-level survey. The presence of original home owners or an active neighborhood organization may indicate opportunities for conducting oral history or viewing community records.

Identifying Significant Patterns of Development

While the significance of a residential suburb depends to a large degree on the local or regional context, the following characteristics generally indicate aspects of a neighborhood's history that may reflect important local or metropolitan trends and should receive further study through an intensive-level survey to verify National Register eligibility.

A wide variety of plans for "architect-designed" small houses were available to local builders in the 1920s and 1930s through architect service bureaus, trade publications, stock-plan businesses, and even savings and loan associations. From top to bottom: Tudor Revival house, Chautauqua Park Historic District, Des Moines (photo by Barbara Beving Long, courtesy of State Historical Society of Iowa); Moderne house, Westheight Manor Historic District, Kansas City, Kansas (photo courtesy Kansas Historical Society); Spanish Colonial Revival house, F.Q. Story Historic District, Phoenix (photo by Robin Baldwin, courtesy Arizona Office of Historic Preservation); Tudor revival house, Glenview Historic District, Memphis (photo by Carroll van West, courtesy Tennessee Historical Commission); English Colonial Revival house, Shaker Village Historic District, Shaker Heights, Ohio (photo by Audra Bartley, courtesy Ohio Historic Preservation Office); Moderne/International Style house, Fort Street Historic District, Boise (photo by Susanne Lichtenstein, courtesy State Historical Society of Idaho).

• The neighborhood's planning and construction related to the expansion of local industry, wartime industry, important stages in metropolitan development, or broad national trends such as returning GI's, the Better Homes movement, and the bungalow craze.
• The neighborhood-through its site plan, overall landscape design, and house design-reflects historic principles of design or achieved high artistic quality in the areas of community planning, landscape architecture, or architecture.
• The subdivider and site planners responsible for the platting and construction of the subdivision figured prominently in the suburban development of the locality or region and made substantial contributions to its character and the availability of housing.
• The neighborhood's design represents the work of one or more established professional designers-site planners, landscape architects, architects, or engineers.
• The subdivision design resulted from the collaboration of professionals representing several fields of design, such as landscape architecture and architecture.
• The neighborhood exemplifies the role that a certain type of developer (subdivider, home builder, community builder, operative builder, or merchant builder) played in the growth and development of the locality or metropolitan region.
• The neighborhood was designed to conform to FHA-standards and represents one of the "earliest," "most successful," "largest," "finest," or "most influential" examples locally.
• Historic neighborhoods possessing a high degree of integrity and exhibiting distinctive elements of design in the subdivision plan, landscape architecture, or domestic architecture.
• Historic neighborhoods reflecting important advances, established principles, or popular trends in community planning or landscape architecture.
• Neighborhoods containing homes in a variety of period styles, or representing the work of one or a number of noted architects.
• Neighborhoods whose housing represents one or more locally important housing types (e.g., bungalows and foursquares).
• Residential neighborhoods associated with important local industries or local events and activities that are known to have stimulated suburban growth and development.
• Neighborhoods historically associated with important events in the Civil Rights movement to provide equal access to housing.
• Neighborhoods associated with important patterns of ethnic settlement that contributed to local growth and development.
• Neighborhoods with homes that received recognition or awards from professional organizations, trade organizations, architectural journals, popular magazines, or housing research foundations.
• Neighborhoods that introduced or established patterns of subdivision design, housing, financing, or building practices that became influential in the local community, metropolitan area, or elsewhere.

Conducting an Intensive-Level Survey and Compiling National Register Documentation:

Intensive-level survey provides a comprehensive study of selected neighborhoods and gathers the detailed information necessary to document properties for National Register listing and make determinations of eligibility. Building upon the general observations made during the reconnaissance survey, the intensive-level survey provides detailed, factual information about the history and physical evolution of one or more subdivisions or neighborhoods believed to be eligible for National Register listing.

The intensive survey closely examines the neighborhood's historic significance, integrity, and boundaries, firmly establishing its place within the local historical context. Survey at this level gathers sufficient information to confirm National Register eligibility and to document the property according to National Register standards.

Documenting the Physical Evolution of a Historic Residential Suburb

During intensive-level survey, additional field observations and research provide an in-depth record of the current character and condition of a historic neighborhood and document its physical evolution and history. The guidelines in Figure 7 list the information that should be gathered during the intensive-level survey and reported on the National Register registration form.

Several historical documents provide valuable comparative data for tracing the physical evolution of a historic neighborhood. A comparison of the neighborhood as it exists today and the original plat helps determine the extent to which the plan was carried out and the periods of time when housing was constructed. Such a comparison will also help determine whether the neighborhood was developed by a subdivider, who consequently sold unbuilt lots to builders, or, by a community builder, who not only sold lots but also supervised the construction of houses. Historic photographs, illustrations, maps and aerial photographs also reveal changes. In addition, fire insurance maps, such as Sanborn Fire Insurance Company maps, drawn soon after the completion of the subdivision, can be compared with more recent maps to identify later construction. Recorded deeds and sometimes tax records provide reliable dates of construction, which can be used to create a series of period maps showing the neighborhood's evolution.

During the intensive-level survey, it is important to document the physical evolution of the neighborhood, identifying who was responsible for the subdivision plan as well as the design of houses and landscape features. This means:

• Determining which profile of developer (e.g. subdivider, home builder, community builder, operative builder, or merchant builder) the developer most closely fits.
• Explaining the relationship between the developer and any site planners, architects, landscape architects, engineers, and home builders who contributed to the design of the neighborhood.
• Documenting the specific contributions of each professional group and of individual designers collaborating on the neighborhood's design.
• Providing documentary evidence that deed restrictions were used, mentioning specific provisions of such restrictions and explaining how they influenced the character of the subdivision.
• Indicating whether the original developer remained in charge of executing the plan and, if not, describing any major changes made by subsequent developers.

Classifying House Types for Inventory Purposes

An intensive survey of one or more residential suburbs often covers an area of considerable extent and literally hundreds of houses and other resources. Decisions need to be made about how houses and streetscapes can be surveyed most efficiently so that determinations can be made about district boundaries and the classification of contributing and noncontributing resources. Sufficient information should be drawn from the reconnaissance survey to determine whether a building-by-building survey is needed or whether there are sufficient similarities of construction and design so that resources can be grouped in categories based on common housing types. Such a typology can then be used to define significant patterns as well as facilitate the collection of information about condition and integrity which is needed to complete the building-by-building inventory of contributing and noncontributing resources.

Many subdivisions, especially during and after World War II, offered prospective owners a limited number of house types, sometimes being distinguished only by the number of rooms, roof design, or exterior wall materials. For this reason, when conducting an intensive survey in a neighborhood of similarly-designed houses, perhaps designed by a single architect and constructed by a single builder, it makes sense to classify houses or housing units by type and provide a general description of each type. An inventory can be compiled by listing each house by street address or building number and indicating its type according to the general classification scheme and noting its condition, any major alterations or additions, and status as contributing or noncontributing.

For example, in an FHA-approved neighborhood having a dozen house types, the description of House Type 2-B might read:

House Type 2-B is a six-room, two-story hipped roof variation of the standard 1144 square foot home whose lower-story is clad with painted brick and upper story wooden clapboard. The house originally featured metal casement windows, a side porch, and a side chimney. A pedimented doorway, paneled door, and a moulded entablature reflect minimal Colonial Revival styling.

An inventory entry for one such house could then read:

1212 Columbus Street, an example of Type 2-B, having an enclosed porch, matching aluminum siding over wooden clapboards on upper story, and replacement double-hung, vinyl windows on principal facades. Otherwise house is in good condition. Contributing.

For more information on documenting historic suburbs, refer to the Documentation and Registration section and the National Register Bulletin, How to Complete the National Register Registration Form.