Felt on the underside of roof sheathing

Anyone ever heard of doing this? The entire attic of this condo had felt paper on the underneath side of the roof sheathing. Any thoughts would be appreciated.

I have some thoughts on it but I don’t think they are going to helpful. Ive never seen this done before, and my thoughts are not going to be fit for general consumption.

I knocked (############ the underside with a hammer handle, but I didn’t stick holes to probe. No staining on the trusses, or rust on the gussets. No ventilation is an issue here as well, but I can write that up, I’m just locked up on the felt thing… The roof was solid to walk on, nice and smooth. Any suggestions on how to write this up?

Could you tell if there was also felt between sheathing and shingles?

I have seen this in my former line of work. Usually by a DIY trying to compensate for a lack of ventilation and poor insulation. Usually doesn’t end up well. Locks alot of moisture in, but the insulation doesn’t get as wet then, right?

Never seen it, wierd. Curious to the find now.

Marcel :slight_smile:

Yes, there was felt underneath the shingles.
Oh, I wish I could figure out the photo posting thing…

Stu, do this tutorialand let me know if you have any trouble.

what kind of shingle wood, comp, tile…

Please explain.

Comp shingles, Barry.

I have seen this twice. Both times the attic was very poorly vented and had a lot of moisure in it. Both times it was explained to me by the home owner that they were told this would keep the sheathing dry. And if any water did happen to accumulate it would not trickle onto the insulation. That is just what I was given as reason when I saw this. Both had very bad looking shingles on the roof by the way.

Since they installed felt under the sheathing worried about drips, I would be curious to find out how long a nail they used to nail the shingles, especially if it was only 1/2" sheathing.

Sounds like a story that might blow away. ha. ha.

Marcel :slight_smile:

I just want to know how they managed to put felt under the sheeting ???

In both case I saw, it was cut in between the joists and stapled to each one. Just senseless to me. But that’s just my opinion.

A good and accurate one, at that!!