Visualising Defects via Thermography (DeViz): A combined technological, behavioural and quality systems approach to achieving near zero defect buildings

Julie Goodhew, Steve Goodhew, João Alencastro, Matthew Fox and Gavin Killip

Abstract

To achieve carbon reduction targets the emissions from buildings need to be near zero. Thermal defects in buildings pose a significant risk to this goal and contribute to energy performance gaps for space heating. A high-performance building envelope is a fundamental requirement towards meeting emissions targets and providing comfort and affordable warmth. Defects in design and installation (e.g., discontinuity of insulation, incorrect detailing, incompatible building systems) can lead to high rates of heat loss, structural damage from moisture build-up and poor user satisfaction. Many defects are invisible upon completion but can be made visible through the correct use of thermal cameras (thermography).

Thermal images can help to improve site operatives’ awareness towards defects, due to their visual appeal. The DeViz research project trains and guides site supervisors, on UK based construction sites, to use thermal cameras at the ‘first fix’ construction stage, when there is still time to remedy defects quickly and cheaply. The aim is to provide new, engaging feedback loops to improve quality control in designing and constructing energy efficient building envelopes and close the design-energy performance gap. DeViz pilots a protocol for overcoming the challenges of; a) achieving the required 10oC temperature difference for imaging, in a mid-construction space, b) accessing the site at the mid-construction point where measurements are meaningful (with the potential for cost effective rectification).

Acknowledging the reluctance of some construction professionals to focus on what could be perceived as their mistakes, DeViz, instead frames defect identification as a ‘normal’ pathway towards better quality, rather than ‘blaming the operative’. We investigate the acceptance of and potential barriers to this intervention with construction professionals, using focus groups and survey methods. We present our learnings to date and discuss the implications for continuous improvement quality systems.

Banner photo credit: Alireza Attari on Unsplash