The UK Home Energy Conservation Act puts a duty on local authorities to develop strategies to improve energy efficiency in all public and private sector housing in order to tackle fuel poverty and reduce carbon dioxide emissions. The City of Nottingham, UK turned to aerial Thermal InfraRed Thermography (TIRT) to try and identify households where energy savings can be made. In this paper, existing literature is reviewed to explain the limitations of aerial TIRT for energy conservation in the built environment and define the techniques required to overcome them. This includes the range of suitable meteorological conditions at the time of the survey, the use of ground truth data, the need to account for all radiation paths and losses when calculating roof surface temperature and the assumptions that must be made when calculating insulation levels. Atmospheric calibration, roof surface emissivity and sky view factor must also be determined by some means and approaches to these problems are reviewed from the wider literature. Error analysis and benchmarking are important if the technique is to be validated and these are discussed with reference to the literature. A methodology for determining the thickness of loft insulation for residential buildings in the city of Nottingham, UK using aerial TIRT data within a GIS software environment is proposed.