Describes an algorithm that calculates heat transfer between the ground and buildings. The algorithm can handle more than 37 building foundation/insulation configurations, including basements, slabs and crawl spaces with full, partial, and no insulation. The solution method on which the algorithm is based is outlined. The required input data are described and references are listed to help the user determine the appropriate values for some of the input parameters. As an application of the algorithm, analyses of the effect of the insulation configuration on heat transfer from both slabs and basements are briefly presented. Spectral sensitivity analysis is conducted to determine the effect of cyclic changes of indoor and outdoor temperature on foundation heat transfer. Finally, implementation of the foundation heat transfer calculation algorithm in a commonly used hourly building simulation program is demonstrated.

KEYWORDS: foundations, basements, heat flow, computer programs, algorithms, calculating, ground, buildings, slabs, crawl spaces, thermal insulation, comparing