Can you put ice and water shield over synthetic underlayment ?
A little over 5 years ago I had my roof replaced . The roofer salesman upsold me an ice and wind shield on the entire roof deck . When they were installing it I think the office never told the installers that the roof was suppose to get the IWS so the entire roof was wrapped with regular synthetic underlayment . Then they found out I was supposed to get the ice and windshield, and they placed the IWS over the synthetic underlayment without removing it . I have original pictures from the installation, showing a large amount of wrinkling in the ice and windshield during the installation process.
Now it’s five years later, I’m selling the home. I had a home inspection point out that my shingles were buckling in some areas. The buyers roofer came over and said the underlayment wasn’t installed properly, and that I need an entire new roof . of course, the roofer that did the work opened a warranty claim with GAF, but I don’t think it’s a claim with a product failure. I think it’s a claim with a product being installed in properly from the beginning
my question is, can you even install ice and windshield over synthetic underlayment because if you cannot, it is definitely a case of being installed incorrectly
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Replies
Dave_De,
It's something you should confirm with the manufacturer, but the installation instructions I can find say "Install Grace Ice & Water Shield® HT roofing underlayment directly on a clean, dry, continuous structural deck. Some suitable deck materials include plywood, wood composition, wood plank, metal, concrete, and gypsum sheathing"
That’s what I read as well . I’d doesn’t say you can or can’t .