Where can you buy ice and water shield, and what should you check before buying?
Short answer. Ice and water shield is sold at roofing supply distributors, which carry the widest range and full rolls by the pallet, and at large home improvement stores, which stock a few common products. Before buying, check that the label says it meets ASTM D1970, confirm the square footage per roll and whether it is rated for high temperatures, and match it to your shingle or metal manufacturer's requirements.
Where to buy
- Roofing supply distributors. They carry many brands and versions, including high temperature and granular-surfaced types, and many sell to homeowners as well as contractors.
- Home improvement stores. Usually a limited selection in stock, with more available by special order.
- Online. Available, but rolls are heavy, so shipping can be costly.
Check the label before you buy
- ASTM D1970. The standard for self-adhering underlayment under steep roofing.
- Coverage per roll. Rolls vary, commonly around 200 square feet. Compare price per square foot, not per roll.
- Temperature rating. Under metal roofing, buy a high temperature version.
- Surface. Granular surfaces give better footing; smooth films are slicker.
- Exposure limit. How long it can sit uncovered.
- Application temperature. If you are working in cool weather, check the minimum.
Match it to the roof system
Shingle manufacturers often count only their own brand of leak barrier toward enhanced system warranties. If you are repairing a roof that has a registered system warranty, using the same manufacturer's membrane avoids questions later. Read roofing warranties explained.
How much to buy
Measure valleys, walls, penetrations and any eaves you plan to cover, add 10 to 15 percent for laps and waste, and divide by the roll coverage. Placement guidance is in ice and water shield in Georgia.