Thermal performance of three deep basements: a comparison of measurements with ASHRAE Fundamentals and the Mitalas method, the European Standard and the Two-dimensional FEM program.

The comparison of four methods for the calculation of deep-basement heat loss is presented along with measured data for three basement types. The Mitalas method was found to give results in best agreement with measured data followed by the finite element method (FEM) program, the European Standard and the ASHRAE Fundamentals method. The studied methods, with the exception of the European Standard of which the physical background was unknown, were chosen because each of them is also representative of a particular physical model of decreasing complexity in the above order. Therefore, differences in presented results yielded by these methods provide insight about differences one can expect when using 3-D, 2-D and/or 1-D physical models for the calculation of deep-basement heat loss. The sensitivity of studied methods to input parameters representing various thermal properties of soils and temperature boundary conditions was investigated also.