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Posted: Jun 29, 2009 02:52 PM	Closed Over Fiberglass We just finished a job this past week where we had to cut out old foam that was partially covering the fiberglass insulation that a metal building company put up. Hurricane Gustav blew open their garage doors and the wind pulled the fiberglass insulation from where it was draped over the pearlings. The foam that was sprayed only had adhesion to the existing insulation forcing all of it to come down. In addition to what we had to cut out, the areas that were not affected, the fiberglass insulation was full of mold from the roof cooling off at night and then heating up the next day causing condensation. I think that the only way to do it correctly is to cut out all of the old insulation, pull it down. If there is still dust up there, you can either blow or spray with denatured alcohol and then spray either open or closed cell to the underside of the roofline. I think that you are right to insist to pull down the old fiberglass insulation.
Posted: Jun 29, 2009 02:58 PM	I actually meant the above post to go under your post. Sorry Steve P.S. If I remember right, you are either from SW La or Eastern Texas. Be forewarned that you will run up against a bunch of yahoo's from my neck of the woods that will spray right over the fiberbags and move on.
Corey Degetaire Posted: Jul 08, 2009 02:05 PM	No problem, Yeah i am from South Central La, I was thinking the same thing about the mold and such. I didn't spray over the old fiberglass for that reason.

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Posted: Jun 29, 2009 02:52 PM

Closed Over Fiberglass

We just finished a job this past week where we had to cut out old foam that was partially covering the fiberglass insulation that a metal building company put up.

Hurricane Gustav blew open their garage doors and the wind pulled the fiberglass insulation from where it was draped over the pearlings.

The foam that was sprayed only had adhesion to the existing insulation forcing all of it to come down.

In addition to what we had to cut out, the areas that were not affected, the fiberglass insulation was full of mold from the roof cooling off at night and then heating up the next day causing condensation.

I think that the only way to do it correctly is to cut out all of the old insulation, pull it down. If there is still dust up there, you can either blow or spray with denatured alcohol and then spray either open or closed cell to the underside of the roofline.

I think that you are right to insist to pull down the old fiberglass insulation.

Posted: Jun 29, 2009 02:58 PM

I actually meant the above post to go under your post.

Sorry

Steve

P.S. If I remember right, you are either from SW La or Eastern Texas. Be forewarned that you will run up against a bunch of yahoo's from my neck of the woods that will spray right over the fiberbags and move on.

Corey Degetaire

Posted: Jul 08, 2009 02:05 PM

No problem, Yeah i am from South Central La, I was thinking the same thing about the mold and such. I didn't spray over the old fiberglass for that reason.

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