Quantitative thermography: A noninvasive method for building envelope R-value measurements
Document Type
Article
Publication Date
9-28-2023
Abstract
The building envelope is a critical contributor to the total building thermal load, especially for residential buildings without significant internal heat gain. However, the envelope R-value is usually acquired from the original design value, regardless of the thermal insulation degrading that has occurred during the whole long lifecycle, the main reason lies in that, with traditional methods, the in situ envelope R-value is extremely inconvenient to measure. In this study, a simple in-situ noninvasive approach was proposed for R-value measurement based on interfacial thermal resistance of the thermal boundary layer between envelope exterior surface and ambient air, and infrared thermal imaging of envelope surface. A field measurement procedure was developed and implemented for a typical detached residential house, along with a widely accepted method using film heat-flux sensors as a validation test. The final results show a good approximation between these two tests, which shows that the proposed method could extend the functions of thermography from only qualitative diagnosis to quantitative measurement on envelope thermal performance.
Publication Source (Journal or Book title)
The Fundamentals of Infrared Thermal Imaging
First Page
21
Last Page
35
Recommended Citation
Zheng, K., Cho, Y., & Wang, C. (2023). Quantitative thermography: A noninvasive method for building envelope R-value measurements. The Fundamentals of Infrared Thermal Imaging, 21-35. Retrieved from https://repository.lsu.edu/construction_management_pubs/460