PERFORMING THE URBAN FORM-BASED CODES AS A METHOD OF ARCHITECTURAL CRITIQUE
Introduction
Form-based codes (FBC) are being adopted in progressive settings throughout the US (Parolek et al. 2008). They are a regulatory system for land development that is usually substituted for the existing zoning code. While zoning is focused on regulating and separating land uses and density, form-based codes are focused on creating a particular physical result, typically a more ordered and somewhat higher density place with a more urban or village-like character. Form-based codes have more flexibility for land uses and density than zoning, but are much more restrictive concerning the design of buildings, sites, and public spaces.
The context
According to the Form-based Code Institute (FBCI), which is an interest group promoting such codes:
Form-based codes foster predictable built results and a high-quality public realm by using physical form (rather than separation of uses) as the organizing principle for the code. They are regulations, not mere guidelines, adopted into city or county law … Form-based codes address the relationship between building facades and the public realm, the form and mass of buildings in relation to one another, and the scale and types of streets and blocks. The regulations and standards in form-based codes are presented in both words and clearly drawn diagrams and other visuals. They are keyed to a regulating plan that designates the appropriate form and scale (and therefore, character) of development, rather than only distinctions in land-use types.
(Form-Based Codes Institute 2013)
Form-based codes (FBC) followed on the popularity of design guidelines, which are usually applied as an overlay on conventional zoning. Design guidelines are quite specifically focused on the design, character, and details of new and renovated buildings, and are common in areas with some historic buildings. In contrast, FBC are a set of regulations applied to specific areas where a particular character is desired. Although the regulations sometimes cover public investments in streets, sidewalks, open space, and the like, the rules we are most concerned with here are those that impact, evaluate, or control architecture.
Like post-occupancy evaluations (POE), FBC are a way of evaluating certain qualities in built form to predict with some accuracy how a building will perform (or does perform) against the ideal situation as reflected in the code. Rules, laws, or guidelines that require a design to measure up to a specific directive are sometimes called “performance” measures. Post-occupancy evaluations, daylight requirements, energy efficiency, and accessibility guidelines are among the proliferating performance tests that a building design can undergo. Because of our computer capabilities, architects now have the means to build performance testing into the models that are created to simulate a building, so that as he or she designs, an architect can get a continuous read-out on whether a design is performing on target against a variety of criteria and rules.
Performance criteria/measures
In the past, architects used their own observations and their own long experience to evaluate a design according to criteria that they developed as a kind of sensibility. As he or she designed, the architect used his or her internal evaluations to guide the work, and thus incorporate them as part of the whole design process. Many things were left out, of course, and it was the designer and the client who prioritized the most important criteria to incorporate. Our tendency in recent years has been to proliferate performance criteria, because we now have the data and the capacity to measure and predict performance beforehand. Even quite complicated performance-based evaluation measures can get built into sophisticated computer simulations of buildings, and the model can then be iterated many times to maximize the fit with various criteria.
While in the past, the client and the architect had the greatest influence on the design, today we must also satisfy a more diverse set of audiences for architecture than was traditionally the case. The public, the government, users (broadly defined), and consumers have begun to insist that buildings perform according to more and more specific criteria. Form-based codes are just one area where a group of citizens, planners, neighbors, and policy-makers have inserted themselves into the traditional design process in order to achieve a public good, like a better urban environment. Most performance evaluations have a public purpose of some kind (safety, access, sustainability, user comfort).
Every performance-based criterion set starts out with an underlying, and somewhat isolated, ideal, such as creating a highly “green” building. By isolated, I mean that this performance specification is neutral with regard to other potential criteria, such as building function. These may conflict: for example, orienting the building to maximize daylight may mean that it fails urbanistic or wayfinding criteria. It is the traditional task of an architect to balance various requirements to create a great building. Soon, it will be the task of the computer to balance the performance criteria, maximizing each according to an algorithm, perhaps dictated by the design team. At present, good designers rarely allow the performance measures to generate the design. In the future, however, the performative criteria may get the upper hand entirely, because the complexity of the models makes the process more and more opaque, even to the designer (Scheer 2014).
Most performance evaluations are based on data. Certainly, people working with post-occupancy evaluations have been doing social science research for decades (see Chapter 19, this volume). This research, as the term “post-occupancy” implies, is gathered by studying built architecture. Sometimes it is based on surveys of occupants, sometimes it is observations of how people use a building, or both. Energy efficiency performance is even more clear-cut and based on the scientifically measured performance of specific materials, systems, and assemblies. This testing is best done in a post-occupancy setting, as well.