- Author
- Treado, S. J.
- Title
- Thermal Resistance Measurements of a Built-Up Roof System. Final Report.
- Coporate
- National Bureau of Standards, Washington, DC
- Sponsor
- Department of Energy, Washington, DC
- Report
- NBSIR 80-2100, October 1980,
- Distribution
- Available from National Technical Information Service
- Keywords
- buildings; roofs; thermal resistance; heat transmission; temperature measuring instruments; infrared equipment; roofing | thermopiles
- Identifiers
- built up roofs
- Abstract
- This report describes factors which affect the thermal performance of built-up roof systems, and a technique for making in-place measurements of thermal resistance. This measurement technique utilizes a combination of infrared thermographic imaging, surface heat-flow meters, and surface thermopiles. The thermal resistance of the roof system is computed based on temperature differences across the roof and the measured heat flow through the roof. A field test of the measurement procedure is detailed, along with an examination of the time period required to perform a roof thermal resistance measurement, as related to the thermal time lag for heat flow through the roof due to the effect of the thermal mass of the roof. Roof thermal resistance determinations performed according to this measurement procedure are found to be very accurate, if measurements are performed over a sufficient time interval, the minimum interval being dependent upon the thermal mass of the roof system.