Soiling of building envelope surfaces and its effect on solar reflectance – Part III: Interlaboratory study of an accelerated aging method for roofing materials

Journal Article · Tue Sep 22 00:00:00 EDT 2015 · Solar Energy Materials and Solar Cells

DOI:https://doi.org/10.1016/j.solmat.2015.07.031· OSTI ID:1378956

Sleiman, Mohamad ^[1]; Chen, Sharon ^[2]; Gilbert, Haley E. ^[2]; Kirchstetter, Thomas W. ^[3]; Berdahl, Paul ^[2]; Bibian, Erica ^[4]; Bruckman, Laura S. ^[5]; Cremona, Dominic ^[6]; French, Roger H. ^[7]; Gordon, Devin A. ^[8]; Emiliani, Marco ^[9]; Kable, Justin ^[4]; Ma, Liyan ^[10]; Martarelli, Milena ^[11]; Paolini, Riccardo  ^[12]; Prestia, Matthew ^[13]; Renowden, John ^[4]; Marco Revel, Gian ^[9]; Rosseler, Olivier ^[14]; Shiao, Ming ^[15] ; Terraneo, Giancarlo ^[16]; Yang, Tammy ^[13]; Yu, Lingtao ^[13]; Zinzi, Michele ^[17]; Akbari, Hashem ^[18]; Levinson, Ronnen ^[2]; Destaillats, Hugo ^[2]

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1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area; Clermont Univ., Clermont-Ferrand (France). Clermont-Ferrand National School of Chemistry (ENSCCF), Inst. de Chimie de Clermont-Ferrand; Centre National de la Recherche Scientifique (CNRS), Aubiere (France)
2. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area
3. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area; Univ. of California, Berkeley, CA (United States). Dept. of Civil and Environmental Engineering
4. Boral Roofing LLC, Irvine, CA (United States)
5. Case Western Reserve Univ., Cleveland, OH (United States). Solar Durability and Lifetime Extension Center; Case Western Reserve Univ., Cleveland, OH (United States). Materials Science and Engineering Dept.
6. Tremco Roofing and Building Maintenance, Beachwood, OH (United States)
7. Case Western Reserve Univ., Cleveland, OH (United States). Solar Durability and Lifetime Extension Center; Case Western Reserve Univ., Cleveland, OH (United States). Materials Science and Engineering Dept.; Case Western Reserve Univ., Cleveland, OH (United States). Macromolecular Science and Engineering Dept.; Case Western Reserve Univ., Cleveland, OH (United States). Physics Dept.
8. Case Western Reserve Univ., Cleveland, OH (United States). Solar Durability and Lifetime Extension Center; Case Western Reserve Univ., Cleveland, OH (United States). Macromolecular Science and Engineering Dept.
9. Univ. Politecnica delle Marche, Ancona (Italy). Dept. of Industrial Engineering and Mathematical Sciences
10. CertainTeed, Malvern, PA (United States)
11. Univ. degli Studi eCampus, Novedrate, CO (Italy)
12. Politecnico di Milano (Italy). Dept. of Architecture, Built environment and Construction engineering
13. GAF Materials Corporation, Wayne, NJ (United States)
14. Saint-Gobain Research Center, Northborough, MA (United States)
15. Collegeville, PA (United States)
16. Politecnico di Milano (Italy). Dept. of Chemistry ,Materials, and Chemical Engineering "Giulio Natta"; FluorIT, Saronno, VA (Italy)
17. Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA-UTEE-ERT), Rome (Italy)
18. Concordia Univ., Montreal (Canada). Dept. of Building, Civil and Environmental Engineering

A laboratory method to simulate natural exposure of roofing materials has been reported in a companion article. Here in the current article, we describe the results of an international, nine-participant interlaboratory study (ILS) conducted in accordance with ASTM Standard E691-09 to establish the precision and reproducibility of this protocol. The accelerated soiling and weathering method was applied four times by each laboratory to replicate coupons of 12 products representing a wide variety of roofing categories (single-ply membrane, factory-applied coating (on metal), bare metal, field-applied coating, asphalt shingle, modified-bitumen cap sheet, clay tile, and concrete tile). Participants reported initial and laboratory-aged values of solar reflectance and thermal emittance. Measured solar reflectances were consistent within and across eight of the nine participating laboratories. Measured thermal emittances reported by six participants exhibited comparable consistency. For solar reflectance, the accelerated aging method is both repeatable and reproducible within an acceptable range of standard deviations: the repeatability standard deviation sr ranged from 0.008 to 0.015 (relative standard deviation of 1.2–2.1%) and the reproducibility standard deviation sR ranged from 0.022 to 0.036 (relative standard deviation of 3.2–5.8%). The ILS confirmed that the accelerated aging method can be reproduced by multiple independent laboratories with acceptable precision. In conclusion, this study supports the adoption of the accelerated aging practice to speed the evaluation and performance rating of new cool roofing materials.

• Research Organization: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Energy Efficiency Office. Building Technologies Office
• DOE Contract Number: AC02-05CH11231; GA-260132
• OSTI ID: 1378956
• Journal Information: Solar Energy Materials and Solar Cells, Vol. 143, Issue C; ISSN 0927-0248
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
54 ENVIRONMENTAL SCIENCES
Cool roofs
Aging
Interlaboratory study
Solar reflectance
Thermal emittance
Soiling
Weathering