To create an airtight envelope, all perforations, overlaps and joints must be sealed using an airtight tape or sealant. Avoid membrane and tape stress during and after installation, so as membrane tears do not occur and the quality of the tape joint is not compromised. Prior to installation, all bonding surfaces should be clean, dry and free of grease, oil, etc. In some applications it might be necessary to prepare the substrate surface with PHS Primer.