A hybrid prescriptive-/performance-based approach to automated building code checking

In design standards and building codes such as the Uniform Building Code (UBC) (ICBO94) or the Americans with Disabilities Act Accessibility Guidelines (ADAAG) (ADAAG97), introductory provisions state the design intent or performance issues of a section, and subsequent prescriptive statements (provisions) outlining the methods to satisfy the design intent. Currently, prescriptive provisions are necessary to explicitly define a standard method to measure the design intent of a section of a design standard. As the provision statement becomes more prescriptive, the design intent is often lost or not fully captured. Consequently, ambiguity and inconsistency arise, thus making the design standard difficult to parse not only by computers, but for humans as well. This paper examines a design-intent approach to design standards processing to alleviate some of the difficulties and complexities of the code due to its prescriptive nature. By focusing on the design intent, it is possible to negate the problems of indeterminacy and conflicting provisions in a building code. There are two major aspects to our design intent approach to design standards processing. First, capture the design intent per each section of the code. Second, formulate and model an adequate performance test of the design intent. The approach is to model the building code's prescriptive statements where there is no indeterminacy and conflict, whereas when such problems surface, a performance-based approach is adapted. This work focuses on disabled access building code issues.