Carlisle Residential WIP 400 Roofing Underlayment (formerly Dri-Start A) is a 40 mil self-adhering sheet membrane. Carlisle Residential WIP 400 is comprised of a strong, skid resistant polyethylene film laminated to a thick layer of highly adhesive rubberized asphalt. A siliconized release sheet is used to prevent the material from sticking in the roll, and is easily stripped away for installation. |
