Assessing the thermal performance of buildings at the construction stage using thermography. Development and evaluation of a testing approach in the context of new housing in Wales

Abstract

At present there are concerns that new housing in the UK under-performs in terms of energy-efficiency. In research studies where the thermal performance of the building fabric has been measured, post-construction, significant gaps between design predictions and the as-built performance of new housing have been found. This thesis is concerned with how thermography may be used to assess the thermal performance of new housing during the construction process. The practical utility of this testing approach, which has not been investigated in-depth by previous research, is to identify performance issues at a stage when undertaking remedial work is less costly and disruptive. Moreover, by identifying issues that could reduce the energy-efficiency of the building fabric, these tests could help address the observed "performance gap". An approach for using thermography at different stages of construction has been developed through practical case studies and experimental work. The complementary use of heat transfer modelling and thermography is also explored. Finally, through interviews with industry professionals, the context of implementing tests within UK housing development practices is examined. The results of applying the testing approach demonstrate that beneficial feedback can be obtained without significant interruption to construction activities. However, test procedures need to be modified according to the stage and method of construction. It is proposed that heat transfer modelling can inform the interpretation of test results and analysis of defect severity. For the testing approach to be implemented more widely, there would need to be further development and trials on different types of construction and the oversight of an independent body to establish its credibility. In conclusion, thermography has the potential alongside other testing and inspection practices to help improve standards of site construction. However, there are limitations to its use which need to be considered if such tests are to be implemented effectively.