Looking for opinions...

Did this inspection on a home built in 2011. Attic is completely sealed off and has spray foam on sheathing. Looked like about 8+ inches of foam. Shingles are loosing a significant amount of granules. If you scrap the shingles with your finger clumps of granular comes off. Roof appeared to be installed nicely. I am leaning toward a manufacture defect. Looking for other thoughts.


I can’t do that with spray foam. Just call that what you see and move on.

? Are you saying it shouldn’t do that with spray foam?

often encounter that degranulation a while after hail, when no apparent damage existed right after the storm
wouldn’t stick my J in the wringer & try to associate it w/spf
contact insurer & mfr rep let them decide

Not my job to guess what is wrong . If you guess incorrectly you could be the fall guy .
Report what you see and move on . Do not make an opinion .

I’m confused.
If the "attic is completely sealed off", how did you determine* ‘the sheathing had 8+ inches of spray foam’ *on it??

I think there is a class about this at the FABI conference upcoming.

Yes there is, and I will be there.

This looks a lot like overheating, but may very well be a manufacturer defect. Warranty might be in jeopardy due to foaming.

Here a link to Certainteed warranty.

I don’t think the foam will be a factor.


+1 to that. Full encapsulation has been used here in Texas for many years and I have heard no reports of negative effects to the shingles. In fact, attic temperatures are much lower with this kind of insulation approach than with others.

I could imagine an incorrectly installed radiant barrier, such as the foil-backed roofing paper I have seen, might cause that, but on a ridge peice? I dunno.

I agree with those who are saying simply report it. Too many unknowables and unseeables to make a diagnosis.

I think what the OP meant by “completely sealed off” is that the attic is completely sealed with foam, AKA, the “full encapsulation” or “beer cooler” approach to spray foam insulation. You still have access to the attic, but air does not circulate up through the soffits and out through gable vents, ridge vents, turbines, and the like.

By sealed off means no ventilation, obviously there was access to the attic. If you look at all the photos you will see the last one is a picture of the spray foam. For foam to be properly installed the attic has to be completely sealed from the exterior. The attic space will become conditioned space.

In my part of the world, this statement includes all access points which are sealed also (which, btw, is now required in new home builds for all openings into the attic space from the living spaces)(that may be a Northern climate thing via DOE).

Yes…I agree. In your neck of the woods I can see an improperly sealed access allowing warm air to enter the attic and cause all kinds of problems in the winter.

May be hail damage

The manufacturers I’ve talked to don’t have a problem with foaming the underside of the sheathing, even though most of them state that it should be ventilated.
Nothing you’ve described sounds like hail damage.
If you suspect manufacturer’s defect, recommend the owner contact a rep BEFORE the sale takes place. warranties don’t always transfer at the time of sale.

How was this determined?

I will try and address some of the comments made…

The 8+ " of insulation is just a guess based the drawings that were present and the way the attic was layed out. This was a very unique custom built home. The designer/builder actually lived it for a couple years after it was built. There may have been less insulation but probably not much less. Anyway, the amount insulation was not in the report. It was merely stated to say that I felt the insulation was more than adequate.

I would say it is definitely not hail damage. I have seen plenty of hail damage and this is not. Besides from on top of this 2nd floor roof I had a very good look at the neighboring houses roof( houses were only about 8’ apart ). One was a standard 3 tab and much older than this roof and had no damage of any kind. So unless hail only hit this house it is very unlikely hail is the culprit.

I kept the comment about manufacture defect out of the report and have heard a roofer went to look it over and thought it was a manufacture defect anyway. Right now the agents are working on contacting the manufacture to see what can be done.

After some more research it does not appear that spray foam will void the warranty, however if the statement that the warranty will not transfer then it is game over anyway, the current sellers are the 2nd owners and my client would be the 3rd owners.

I would like to thank all you responded to this.

I believe it’s called blistering, caused by excessive heat. I was a roof inspector in California and saw this often. Usually caused by improper ventilation.

I have trouble opening some of those photos, but was able to get a close up view today.

In areas where granules are missing you can see indentations in the asphalt indicating that the failure is granule adhesion, not bonding failure along a plane in the asphalt layer. So sections of asphalt are not coming loose, but there are scattered areas across the roof where different sized groups of granules failed to adhere to the asphalt. Very different from uniform granule loss, which is fairly common.

This condition may or may not be functional damage (shorten the service life of the shingle or reduce its ability to shed water) but it sure looks like a manufacturing problem to me, and if I were the seller, I’d be contacting the manufacturer hoping for a full roof replacement.