The joint influence of albedo and insulation on roof performance: An observational study
Abstract
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 heatingmore »
- Authors:
-
- 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.
- Publication Date:
- Research Org.:
- Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 1254734
- Alternate Identifier(s):
- OSTI ID: 1360833
- Report Number(s):
- PPPL-5120
Journal ID: ISSN 0378-7788; PII: S0378778815001450
- Grant/Contract Number:
- EE0004261
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Energy and Buildings
- Additional Journal Information:
- Journal Volume: 93; Journal 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.; Journal ID: ISSN 0378-7788
- Publisher:
- Elsevier
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; Cool roof; Roof albedo; Roof heat flux; Roof insulation
Citation Formats
Ramamurthy, P., Sun, T., Rule, K., and Bou-Zeid, E. The joint influence of albedo and insulation on roof performance: An observational study. United States: N. p., 2015.
Web. doi:10.1016/j.enbuild.2015.02.040.
Ramamurthy, P., Sun, T., Rule, K., & Bou-Zeid, E. The joint influence of albedo and insulation on roof performance: An observational study. United States. https://doi.org/10.1016/j.enbuild.2015.02.040
Ramamurthy, P., Sun, T., Rule, K., and Bou-Zeid, E. Mon .
"The joint influence of albedo and insulation on roof performance: An observational study". United States. https://doi.org/10.1016/j.enbuild.2015.02.040. https://www.osti.gov/servlets/purl/1254734.
@article{osti_1254734,
title = {The joint influence of albedo and insulation on roof performance: An observational study},
author = {Ramamurthy, P. and Sun, T. and Rule, K. and Bou-Zeid, E.},
abstractNote = {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.},
doi = {10.1016/j.enbuild.2015.02.040},
journal = {Energy and Buildings},
number = C,
volume = 93,
place = {United States},
year = {Mon Feb 23 00:00:00 EST 2015},
month = {Mon Feb 23 00:00:00 EST 2015}
}
Web of Science
Works referenced in this record:
Evolution of Cool-Roof Standards in the US
journal, January 2008
- Akbari, Hashem; Levinson, Ronnen
- Advances in Building Energy Research, Vol. 2, Issue 1
Cooling the cities – A review of reflective and green roof mitigation technologies to fight heat island and improve comfort in urban environments
journal, May 2014
- Santamouris, M.
- Solar Energy, Vol. 103
Quantifying the direct benefits of cool roofs in an urban setting: Reduced cooling energy use and lowered greenhouse gas emissions
journal, February 2012
- Xu, Tengfang; Sathaye, Jayant; Akbari, Hashem
- Building and Environment, Vol. 48
Green Roofs as Urban Ecosystems: Ecological Structures, Functions, and Services
journal, November 2007
- Oberndorfer, Erica; Lundholm, Jeremy; Bass, Brad
- BioScience, Vol. 57, Issue 10
Cool surfaces and shade trees to reduce energy use and improve air quality in urban areas
journal, January 2001
- Akbari, H.; Pomerantz, M.; Taha, H.
- Solar Energy, Vol. 70, Issue 3
A green roof model for building energy simulation programs
journal, January 2008
- Sailor, D. J.
- Energy and Buildings, Vol. 40, Issue 8
Experimental investigation and numerical simulation analysis on the thermal performance of a building roof incorporating phase change material (PCM) for thermal management
journal, April 2008
- Pasupathy, A.; Athanasius, L.; Velraj, R.
- Applied Thermal Engineering, Vol. 28, Issue 5-6
Green roofs; building energy savings and the potential for retrofit
journal, October 2010
- Castleton, H. F.; Stovin, V.; Beck, S. B. M.
- Energy and Buildings, Vol. 42, Issue 10
Before and after retrofit – response of a building during ambient and strong motions
journal, September 1998
- Çelebi, M.; Liu, H. -P
- Journal of Wind Engineering and Industrial Aerodynamics, Vol. 77-78
Bright is the new black—multi-year performance of high-albedo roofs in an urban climate
journal, January 2012
- Gaffin, S. R.; Imhoff, M.; Rosenzweig, C.
- Environmental Research Letters, Vol. 7, Issue 1
Measurement of albedo and analysis of its influence the surface temperature of building roof materials
journal, April 2005
- Prado, Racine Tadeu Araújo; Ferreira, Fabiana Lourenço
- Energy and Buildings, Vol. 37, Issue 4
A Model of Aging for Gas-Filled Cellular Plastics
journal, July 1988
- Bomberg, M.
- Journal of Cellular Plastics, Vol. 24, Issue 4
Heat fluxes through roofs and their relevance to estimates of urban heat storage
journal, July 2009
- Meyn, Stephanie K.; Oke, T. R.
- Energy and Buildings, Vol. 41, Issue 7
SensorScope: Application-specific sensor network for environmental monitoring
journal, February 2010
- Ingelrest, François; Barrenetxea, Guillermo; Schaefer, Gunnar
- ACM Transactions on Sensor Networks, Vol. 6, Issue 2
A coupled energy transport and hydrological model for urban canopies evaluated using a wireless sensor network
journal, October 2012
- Wang, Zhi-Hua; Bou-Zeid, Elie; Smith, James A.
- Quarterly Journal of the Royal Meteorological Society, Vol. 139, Issue 675
Synergistic Interactions between Urban Heat Islands and Heat Waves: The Impact in Cities Is Larger than the Sum of Its Parts*
journal, September 2013
- Li, Dan; Bou-Zeid, Elie
- Journal of Applied Meteorology and Climatology, Vol. 52, Issue 9
Works referencing / citing this record:
Validation of Calibrated Energy Models: Common Errors
journal, October 2017
- Ruiz, Germán; Bandera, Carlos
- Energies, Vol. 10, Issue 10