Formulation of an OTTV for walls of bedroom in Thailand

Air-conditioning has penetrated to a significant extent in urban households and is increasingly used in all areas in Thailand. Building envelope is the most significant component that affects energy performance of an air-conditioned building. This paper reports results of an attempt to formulate a measure of performance of building envelope enclosing space used under bedroom function. The overall thermal transfer value form of the measure that comprises a heat gain through opaque wall term, a solar radiation gain term, and a conduction heat gain through glazing term proves to apply well. The formulation is validated through the use of two simulation programs on two residential building models with significant variations of the envelope thermal parameters. The work is a part of an effort in an international research program to develop a scheme for rating energy and carbon performance of residential buildings.