Thermal capacity of furniture is ignored, as is heat storage beyond the first 4 inches of mass thickness.
All mass is assumed to be in direct contact with the conditioned space .
It also assumes exterior wall , interior wall and ceiling surface area approximately equals three times the floor area. This category includes masonry fireplaces, water or trombe walls and extra layers of sheetrock. Adjustments for slab covering is based on R value of material. Additional mass values are based on the density multiplied by the specific heat of the material adjusted for listed thickness. DCLU moved to Key Tower in Spring 2001.