Aging and weathering of cool roofing membranes
Aging and weathering can reduce the solar reflectance of cool roofing materials. This paper summarizes laboratory measurements of the solar spectral reflectance of unweathered, weathered, and cleaned samples collected from single-ply roofing membranes at various sites across the United States. Fifteen samples were examined in each of the following six conditions: unweathered; weathered; weathered and brushed; weathered, brushed and then rinsed with water; weathered, brushed, rinsed with water, and then washed with soap and water; and weathered, brushed, rinsed with water, washed with soap and water, and then washed with an algaecide. Another 25 samples from 25 roofs across the United States and Canada were measured in their unweathered state, weathered, and weathered and wiped. We document reduction in reflectivity resulted from various soiling mechanisms and provide data on the effectiveness of various cleaning approaches. Results indicate that although the majority of samples after being washed with detergent could be brought to within 90% of their unweathered reflectivity, in some instances an algaecide was required to restore this level of reflectivity.
- Research Organization:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE. Assistant Secretary for Energy Efficiency andRenewable Energy.Office of the Deputy Assistant Secretary for TechnologyDevelopment. Office of the Building Technologies Division
- DOE Contract Number:
- DE-AC02-05CH11231
- OSTI ID:
- 860745
- Report Number(s):
- LBNL-58055; R&D Project: EK241L; BnR: 600303000; TRN: US200524%%307
- Resource Relation:
- Conference: First International Conference on Passive and LowEnergy Cooling for the Built Environment, Athens, Greece, May 17,2005
- Country of Publication:
- United States
- Language:
- English
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