This thesis presents a body of work conducted in the field of domestic thermal comfort. The aim of this research was to determine the suitability of the Predicted Mean Vote (PMV) index in homes within the UK. Two field studies were conducted with a sample of participants living in owner occupied properties in a UK city (London) and a UK provincial town (Loughborough). Research findings indicate that the PMV is indeed a good predictor of thermal sensation in homes when conditions are steady state and people are engaged in near-sedentary activities. When conditions are not steady state and people are engaged in a variety of household activities, the accuracy of the PMV index can be improved by using a metabolic rate coefficient of 1.7. Further research work is required to ascertain this and likewise the range of applicability of the Adaptive Model.