The June 2009 issue of Consumer Reports magazine includes an article providing ratings for 26 popular asphalt shingle products. If you install asphalt shingles, I encourage you to be aware of this Consumer Reports article and my concerns with the information it provides.
Ratings
Consumer Reports' article rates 18 architectural laminate and eight conventional three-tab asphalt shingle products based on price, overall score, weight, test results and warranty. Test results are based on strength, wind, weathering and impact and reported using the nonquantitative terms "excellent," "very good," "good," "fair" and "poor."
All the evaluated products are rated as good, very good or excellent for strength, weathering and impact. However, for wind test results, one product is rated as excellent; 13 products are rated as good; and 12 products are rated as poor.
Consumer Reports does not specify the number of samples obtained and tested, test methods employed and criteria used to distinguish between different ratings.
Comparing results
Comparing Consumer Reports' test results with recognized, consensus-based laboratory tests routinely conducted and reported by asphalt shingle manufacturers and others reveals conflicts with some of the article's test results.
ASTM D3462, "Standard Specification for Asphalt Shingles Made from Glass Felt and Surfaced with Mineral Granules," provides consensus test methods to determine tear strength and fastener pull-through. Although Consumer Reports' strength test ratings range from good to excellent, a review of manufacturers' product literature reveals all the products comply with ASTM D3462.
Asphalt shingles' wind resistance typically is evaluated using ASTM D3161, "Standard Test Method for Wind-Resistance of Asphalt Shingles (Fan-Induced Method)" and/or ASTM D7158, "Standard Test Method for Wind Resistance of Sealed Asphalt Shingles (Uplift Force/Uplift Resistance Method)." The product Consumer Reports rates as having excellent wind test results has ASTM D3161, Class F and ASTM D7158, Class H classifications (highest levels). However, 20 other products Consumer Reports rates as having good or fair wind test results also have ASTM D3161 and ASTM D7158 classifications.
Asphalt shingles' impact (simulated hail) resistance typically is evaluated using UL 2218, "Standard for Impact Resistance of Prepared Roof Covering." Three of the products Consumer Reports rates as having excellent impact test results have a UL 2218, Class 4 (highest level) classification. Another product Consumer Reports rates as having excellent impact test results is classified as UL 2218, Class 2. Nine other products the article rates as having excellent impact test results are not classified by UL 2218.
Closing thoughts
Although Consumer Reports is recognized for providing useful information to help consumers select products, I am concerned its article addressing asphalt shingles will mislead homeowners.
It is apparent Consumer Reports did not use testing and evaluation methods (and likely sampling methods) recognized as appropriate for asphalt shingles. Unlike many other products Consumer Reports evaluates, asphalt shingles have well-established test and performance evaluation methods. ASTM D3462, ASTM D3161, ASTM D7158 and UL 2218 are consensus-based standards and required for compliance with most building codes. In some cases, Consumer Reports' test results clearly are not consistent with results of recognized and required methods.
Many homeowners may be aware of Consumer Reports' article; you should be prepared to explain how the products you recommend compare with the article's findings.
Mark S. Graham is NRCA's associate executive director of technical services.
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