simple box model

ASHRAE Standard 209 defines a simple box model and describes how you create one. It is supposed to be going out for a second public review but I am not sure when. There are no real hard and fast rules for this however. This model is supposed to be completed before there is any building design. It is supposed to be representative of what will be built, similar area, number of floors, etc. The creation of thermal zones is probably at the perimeter/core level or something simple that makes sense. The purpose is to understand the potential distribution of energy by end use and to begin evaluating possible strategies to include in the development of the design. The term, I think, comes from ASHRAE 90-1989 where the baseline was actually a simple box instead of mostly being the same configuration as the proposed. So if you can find an old copy of that standard it would also give you an idea of what it is.