The joint influence of albedo and insulation on roof performance: An observational study
- City College of New York, NY (United States); Princeton Univ., NJ (United States)
- Tsinghua Univ., Beijing (China). Hydraulic Engineering Dept.
- Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
- Princeton Univ., NJ (United States). Civil and Environmental Engineering Dept.
We focus on understanding the temperature and heat flux fields in building roofs, and how they are modulated by the interacting influences of albedo and insulation at annual, seasonal and diurnal scales. High precision heat flux plates and thermocouples were installed over multiple rooftops of varying insulation thickness and albedo in the Northeastern United States to monitor the temperature and the heat flux into and out of the roof structures for a whole year. This analysis shows that while membrane reflectivity (albedo) plays a dominant role in reducing the heat conducted inward through the roof structures during the warmer months, insulation thickness becomes the main roof attribute in preventing heat loss from the buildings during colder months. On a diurnal scale, the thermal state of the white roof structures fluctuated little compared to black roof structures; membrane temperature over white roofs ranged between 10 °C and 45 °C during summer months compared to black membranes that ranged between 10 °C and 80 °C. Insulation thickness, apart from reducing the heat conducted through the roof structure, also delayed the transfer of heat, owing to the thermal inertia of the insulation layer. Furthermore, this has important implications for determining the peak heating and cooling times.
- Research Organization:
- Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
- Sponsoring Organization:
- USDOE
- Grant/Contract Number:
- EE0004261
- OSTI ID:
- 1254734
- Alternate ID(s):
- OSTI ID: 1360833
- Report Number(s):
- PPPL-5120; PII: S0378778815001450
- Journal Information:
- Energy and Buildings, Vol. 93, Issue C; Related Information: This work was supported by the U.S. Department of Energy through Pennsylvania State University's Energy Efficiency Building Hub under grant No. DE-EE0004261 and by the Helen Shipley Hunt Fund through Princeton University.; ISSN 0378-7788
- Publisher:
- ElsevierCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
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