TABLE OF CONTENTS Since UFAD technology is relatively new to the building industry, its characteristics may require consideration of unfamiliar code requirements and, in fact, may be in conflict with the provisions of some existing standards and codes. Applicable standards should be reviewed carefully; revisions and exceptions that are more compatible with UFAD technology will likely be forthcoming as additional research results are obtained. Local building codes and the interpretations of local officials should be considered early in the design process of a building using underfloor air supply plenums. Experience has shown that the first UFAD project in an area governed by an unfamiliar jurisdiction will usually end up establishing the "ground rules" for code interpretations on future projects.
Listed below are brief discussions of the applicable building standards and codes that have important provisions related to the design, installation, and operation of UFAD systems. In addition, a brief description of the LEED (Leadership in Energy & Environmental Design) Rating System is provided.
Earlier versions of Standard 55 were based on the assumption of a well-mixed and uniformly conditioned environment. UFAD systems, however, usually involve greater variability of thermal conditions over both space and time. The effect of providing occupant control has not been fully taken into account, although it is well established that occupants will tolerate greater fluctuations in environmental conditions if they have control over them. The rather strict air velocity limitations that were specified in the previous...
