This study addresses the problem of increasing the utility of thermal imaging by survey with calibration data. The present practice is to interpret the temperature differentials across uniform surfaces and make comparisons among surfaces of uniform emissivity. Collection of digital data permits rapid manipulation of the data. The data is in a format suitable to computational analysis in a heat-loss algorithm. Data can also be displayed on a cathode ray tube for interactive analysis. It is expected that the aerial thermal images obtained in experiments and analysis will identify and quantify those parameters related to heat transfer through the roof surface and demonstrate that thermal imaging identifies those buildings having excessive heat losses.