Dimensional analysis was used to derive the physical properties for a small-scale model building and its heating, ventilating, and air conditioning (HVAC) system. The model was built, and its thermal response was studied over a number of heating and cooling cycles. Temperature variation was recorded in the form of temperature/time plots. Experimental results showed the model to be capable of realistic behaviour. Detailed comparisons with full-scale response could not be made, since an imaginary prototype was assumed. Recent computer simulation, however, produced results analogous to those obtained from the model tests. This suggests that small-scale models can be used to quantitatively reproduce building energy response. Current efforts are being directed towards the modelling of an existing building, in which both air temperature and velocity will be measured. The aim is to validate small-scale modelling as a viable tool in building-energy research.