Abstract
Glass fiber-reinforced asphalt shingles have experienced cracking for some time. The issue of how to evaluate tear strength has also been discussed. What has been overlooked is the effect moisture and heat have on the tear strength of glass fiber shingles. Fifteen lots of new shingles were evaluated using a condensation cycling protocol along with heat aging. Large differences in tear strength were observed depending on which protocol was used. Shingle tear strength was found to generally be diminished by moisture cycling; the strength loss can be regained by heat conditioning.
Glass fiber-reinforced asphalt shingles have experienced cracking for some time. The issue of how to evaluate tear strength has also been discussed. What has been overlooked is the effect moisture and heat have on the tear strength of glass fiber shingles. Fifteen lots of new shingles were evaluated using a condensation cycling protocol along with heat aging. Large differences in tear strength were observed depending on which protocol was used. Shingle tear strength was found to generally be diminished by moisture cycling; the strength loss can be regained by heat conditioning.
Date
9/2002
9/2002
Author(s)
Rene Dupuis; Mark Graham
Rene Dupuis; Mark Graham
Page(s)
Keyword(s)
glass fiber; asphalt shingle; cracking; moisture; heat; tear strength
glass fiber; asphalt shingle; cracking; moisture; heat; tear strength