ZONING DESIGN SPECIFICATIONS: Expanding the Language of Urban Design

Note: Table 1 is located at the end of this text. The complete book can be found on Amazon.com.

Zoning ordinances attempt to lead the increment-

al growth of urban areas with a vocabulary that has not consistently produced success and avoided failure. It addresses the Shelter Division of a Built Domain that is served by its Movement, Open Space, and Life Support Divisions, but its success to date can be summarized with the terms “sprawl” and “over-development”. Random success has received awards that hope to encourage similar results, but these awards struggle with inadequate measurement, evaluation, and direction toward the success pictured but not adequately defined. This arbitrary pattern of success and failure can be improved with an amended vocabulary of zoning specification and the design leadership it enables.

The gray boxes in Table 1 combine to define the characteristics of a building served by grade parking around, but not under, the building. The shelter design alternative is referred to as G1. In this example, gross land area is given and its capacity to accommodate gross building area is to be found. Answers depend on the values and floor quantity options entered in the gray design specification boxes of Table 1. The values entered are processed by the algorithm noted in the Planning Forecast Panel of Table 1. Optional line item answers are related to the floor quantity alternatives entered in cells A44-A53. The line item implications of each gross building area option are calculated in the adjoining Implications Module.

Shelter capacity, or gross building area per buildable acre, is calculated in Col. F of the Planning Forecast Panel and may be occupied by any activity. It is a critical piece of planning information that will determine our ability to shelter the activities of growing populations, without excessive intensity, within geographic limits that do not expand to consume our source of life.

The G1 design values entered in the gray specification boxes of Table 1 define the relationship of building mass and service pavement to the amount of offsetting unpaved open space provided. The master equation in cell B39 is used to predict the gross building area options presented in Col. B of the Planning Forecast Panel. When the forecasts are divided by the buildable acres occupied, the shelter capacity options in Col. F are produced. The intensity of these options is measured in Col. G to compare increasing shelter capacity with its intensity implications.

Gross building area alternatives produce measurable levels of shelter capacity, intensity, intrusion, and dominance within the neighborhoods, districts, cities, and regions they combine to create. These implications are calculated at the cellular level in the Implications Module of Table 1. A change to one or more of the values entered in the gray specification boxes of a design specification template will produce a new set of planning forecasts and implication measurements.

A chosen shelter capacity and intensity alternative can be defined by the specification values that are correlated to create the option. Thousands of technical form, function, and appearance decisions ensue to define a final product, but the foundation is established with these initial urban design decisions. The G1.L1 forecast model presented in Table 1 enables measurement, evaluation, prediction, and definition. The topics and values involved create an urban design vocabulary that can be used for knowledge formation and leadership improvement within a Built Domain that must be limited to coexist with its source of life – the Natural Domain.

When values are entered in the gray boxes of Table 1, they define the contents of a G1 cell in the urban anatomy. An algorithm correlates these choices to calculate leadership information. The correlation produces a prediction of options in a Planning Forecast Panel and a prediction of implications in an Implications Module. These predictions will change whenever one or more of the values in the specification are modified. The process offers the opportunity to measure existing conditions and predict future capacity and intensity options with a consistent set of criteria that permit comparison and evaluation of the implications calculated. As a result, success can be measured, failure can be avoided, and knowledge can be accumulated on a track parallel to that of traditional aesthetic criticism.

A zoning ordinance attempts to consistently produce the results intended by the master plan it supplements based on a concept of minimum standards that are written to protect the public’s health, safety, and welfare. The problem has been that these standards have not been mathematically correlated. The resulting contradictions have been one source of “hardship” variance requests and inconsistent judgments by appointed residents from the community. Table 1 resolves this issue for the G1 Building Design Category by mathematically correlating the design topics and items that interact to produce gross building area results for any given land area; and it calculates the capacity, intensity, intrusion, and dominance implications produced by a set of value entries. The fact that these values can be modified to produce alternative results presents the opportunity to evaluate and define correlated sets of minimum standards with the confidence that they will produce the implications forecast.

Table 1 illustrates the use of one fail-safe measure that deserves special mention. The total unpaved open space percentage of a buildable land area must be specified in cell F11. This can be either a planned, present, or required percentage; but the entire topic is often overlooked, ignored, or marginalized in an effort to maximize the gross building area and parking potential of a given land or lot area. When it is ignored, the intensity added to the neighborhood is unknown and the runoff produced by excessive impervious cover is rarely correlated with the storm sewer capacity present or planned. Cell F11 in Table 1 ensures that unpaved open space is included as a conscious decision and correlated within a complete design specification.

The aggregation of unpaved cellular open space can lead to open space arteries that let urban anatomies breathe. Its absence adds to the suffocation of body and soul; but if this argument does not resonate, the absence of unpaved open space has also led to serious flooding implications. A conscious consideration of unpaved open space as a portion of cell content on every lot in a city will be one step toward the arteries of open space needed to breathe life into the urban forest of building mass and pavement we travel seeking the green places we left.