Technical Bulletin #24
Current as of JUNE 2019
Asphalt shingles are manufactured with a factory-applied asphalt adhesive sealant strip. In order to prevent the sealant strip from sticking the shingles together in the package, a release film is embedded on the shingle during the manufacturing process.
The release film is aligned over the sealant strip to prevent the sealant from “sticking” while the shingles are in the bundle. In addition, the sealant on the top shingle in each package is protected from sticking to wrapper by a special treatment applied in that area of the wrapper.
Once the shingles are unpacked, the release film has served its purpose and should simply be left in place. Release films on the back of asphalt shingles also don’t need to be removed.
The information contained in this bulletin is for general education and is not intended to replace advice from a qualified contractor or direction on usage/installation from the manufacturer. Consumers should be aware of the safety hazards associated with work on roofs and, before doing so themselves, should consider following CASMA s advice of using qualified contractors. This bulletin may be reproduced with permission on condition that it be reproduced in whole, unedited, with attribution of copyright to CASMA.
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