Radiative Heat Loss Estimation of Building Envelopes based on 3D Thermographic Models Utilizing Small Unmanned Aerial Systems (sUAS)

Abstract The advent of sUAS (small unmanned aerial systems – or surveying drones) technology has made comprehensive thermographic analyses of the built environment feasible. Advantages over traditional thermal survey techniques include a significant increase in ease of three-dimensional (3D) navigation around large structures as well as the ability to perform data-rich measurements. 3D building envelope thermographic models represent the building surface temperatures and can be created using structure-from-motion photogrammetry techniques with the collected high-overlap sUAS thermographic images. This paper introduces an end-to-end workflow for measuring radiative heat loss from building envelopes. This includes the setup and process required for quickly creating accurate 3D thermographic models and their analysis with software developed for this purpose. Three analytical models for building envelope radiative heat loss are applied and tested for viability through controlled experiments. The workflow is then demonstrated by evaluating the thermal radiation losses of two buildings on the campuses of the University of North Georgia. Our findings suggest the workflow can quickly provide good radiative heat loss measurements and may be a valuable addition to more comprehensive thermal analysis techniques.