The dome-covered house is an example of designing buildings by learning from the optimized biological forms from the nature in order to reduce the energy use for heating in cold climates. This paper presents the three-dimensional thermal and airflow (3D-TAF) model that predicts the impact of such dome on the heating load of the protected house. The emphasis is on the airflow model, the formulation of the system of equations, the calculation procedure, and the comparison with a CFD model. A case study of a dome located in Montreal (Canada) is presented. A linear correlation model is developed that predicts the variation of the dimensionless air temperature inside the dome with the dimensionless height. (C) 2007 Elsevier B.V. All rights reserved.