Gracesickles?

I've been running into this quite a lot here in nassau. I suspected it was grace but most of it has been coming from under metal roofs so I couldn't check to see. This is the first I've seen it under fiberglass/asphalt shingles which I was able to lift and see for sure. I know people are gonna blame it on the heat but I've seen it coming from under white metal which remains cool no matter what. Anyone else seen this before?

These pictures help explain something that I have observed. For some time Grace I&W has been cut into strips and used as a substitute ridge tape under tile roofs. I have, on multiple occasions, observed degradation of the Grace when used as such. But the actual worst of it, where there's actually a hole in the Grace, doesn't occur where the Grace rests on the tile even though that is the spot least shaded and most likely to get UV rays.

The holes occur in the spot where the Grace is unsuborted uderneath, where it spans from the tile surface to the hip nailer. I had assumed that it was from heat build-up from under the tile, but now I'm comvinced it's because Grace bleeds on the underside wherever it isn't down on a solid surface.

CM, I beg to differ. First off, It wasn't being exposed, it was hanging out freely, but still covered, there's a difference. If you look at the pics, you can see that the Grace changes in color and composition right at the edge because that is where is started bleeding. If you look where the edge is lifted, there are no signs of it running down from above, it all came from the part hanging over the edge.

Now I have no doubt that Grace had enough problems with heat that the whole subclass of HT underlayments was required, but that doesn't change what I see in those pictures.

Wywoody being exposed has nothing to do with it. I've seen it bleed out from under shingles on steep roofs. My first thought was Ole Jack had installed the skylight but when we pulled it apart it was in fact grace bleeding

Thanks Jack for getting me to revisit this post. I just noticed that all the dripping could be coming from the part of the Grace that is hanging free out over the edge-which is against the specs for installing it. There may be reasons for maligning the stuff, but this might not be a good example.

ARRRRRRRRRRR..AHOY THER..WELL SHIVER ME TIMBERLINES...LOOKS LIKES OLE JACKS CALLIN CARD FOR SUUUUUURE....ARRRRR..A MITE PERTY..AINT IT??

Not to surprised, even though it is a miracle cure for crap installations.

Branden, nice "Thumb" I have never seen it that bad. It looks like it has cooked the bituimen enough so that the grace is not even sticking anymore. When they first came out with it about 35 years ago, they sold the same stuff for the roofs as they do for underground waterproofing. That had a lot more of the asphalt on it and was slippery as all get out on the surface, dangerous in fact. It looks like they used some type of a wrong mix on that roll or any of the jobs you have seen it running on as it should not be doing that.

But hey, it is code right, and I KNOW you just love that. Hang in there.

Yes I see it all the time on steep roofs were it was used around chimneys and skylights

I have heard of this happening under metal roofs never seen it. Looks like Grace to me