How do you remove ice and water shield from a roof?
Short answer. Usually you do not remove it cleanly: self-adhered membrane bonds to the deck, so during a tear-off it is scraped off where it releases and the decking is replaced where it will not. For small areas, warming the membrane with a heat gun and working it off with a flat bar or scraper can help, but expect to damage the wood surface.
Why it fights back
The adhesive in a rubberized asphalt membrane keeps bonding to the wood for years. By the time a roof is replaced, it is often fused to the top veneer of plywood or the surface strands of OSB. Pulling it lifts wood with it.
Methods that work
- Scraping. A roofing shovel or flat scraper slid under the edge works best on cool mornings when the membrane is stiffer and releases in larger pieces.
- Gentle heat. On small areas, a heat gun softens the adhesive so it can be peeled slowly. Keep the heat moving and never use an open flame on a wood deck.
- Replacing the sheet. On larger areas, cutting out and replacing the decking is often faster and leaves a clean surface for the new roof.
Can new membrane go over old residue?
It depends on the manufacturer of the new product. Many require a clean, dry, smooth deck, and adhesive residue, torn wood and leftover granules can keep new membrane from bonding properly. When in doubt, replace the affected sheets.
Safety and cleanup
- Wear gloves and eye protection; scraped asphalt is sticky and sharp edges of torn deck can splinter.
- Keep debris off shingles you are keeping and out of gutters.
- Dispose of membrane with other roofing debris.
What it means for your estimate
If your roof has membrane at the eaves and valleys, expect some decking replacement there during tear-off. Ask for the per-sheet decking price in writing. Panel choices are compared in OSB vs plywood roof decking, and membrane basics are in ice and water shield in Georgia.