GAF Shingle Mate

Well I learned something new today, GAF Shingle Mate is not waterproof nor is it even water resistant. What is the point of putting down an underlay if it can’t even resist water?? Even #15 old fashioned tar paper is water resistant to an extent.

I was surprised to read the product info where it says “Shingle-Mate® Roof Deck Protection must NOT be left exposed to moisture or precipitation.”

I still have ceiling stains from getting caught in a storm and only had that down. Now, I tarp whatever is down if it’s open to the weather.
I peeled Deck Armor back on a job and found the plywood wet. I waited 4 hours to let it dry before starting work.
A Canadian Co. still makes a good 15 pound,a nd 30 pound UL felt. Both are about 40% larger rolls than the #15 and #30 junk they sell.
More new ‘felts’ appear to be tarps without the stitched in rope on the edges and lack the grommets.

We normally use HAL Industries #15 and #30 felt (44"), and it is completely water resistant. But we use this shingle mate crap only on the GAF system roofs. Crap underlay for crap shingles I guess :biggrin:

“Crap underlay for crap shingles I guess”
Yep! :smiley:

Shingle mate is kind of slippery also, what a wonderful property for a roofing underlayment to have… :roll:

[quote=“bcdemon”]Well I learned something new today, GAF Shingle Mate is not waterproof nor is it even water resistant. What is the point of putting down an underlay if it can’t even resist water?? Even #15 old fashioned tar paper is water resistant to an extent.

I was surprised to read the product info where it says “Shingle-Mate® Roof Deck Protection must NOT be left exposed to moisture or precipitation.”[/quote]

Not sure this means it’s not water resistant. Like most felts it will bubble when wet. I’ve dried in new construction with it in the past with no leaks

Slave, I used a piece of it to keep my tool bag dry while I was roofing over this stuff in the rain. When I finished I pulled the piece off my bag and both sides were soaked, my bag was damp too.

“GAF shall assume no liability for damaged caused by the adaptation of this product for purposes other than it’s intended use”

Looks like you’re screwed :mrgreen: