Foam insulation on Pole Barn steel... "bulges"?...

[BoxMN]

My buddy built a nice 60x80 pole barn, and is finishing it off ina 30x30 corner for a cabin type living area. He ended up going with spray foam insulation. All went well, but on the outside tin, there is a slight "bulging" right along the perlins/2x6's whatever they are called that run the length of building were tin was screwed on. He is kinda picky, and said some people might not even notice it, but I can see it in the pics. Not real bad... no real way to "fix" it.

I am just wondering if this is common for tin buildings with spray foam insulation sprayed right against the tin? The guys sdaid they applied it properly, but said they haven't really seen that happen before either. Anybody know if this is common in application like this? He is a bit worried that if he ever needs to retin for any reason, that the new piece won't fit on properly. Good thing is it is on the back side from the road so only see it from behind the building. Thanks for any thoughts.

[reddog]

I dont think it should have bowed from the foam, unless it was an encapsulated install, where the foam had nowhere to expand. It shouldve just expanded to the inside, and not caused a problem. Only thing I can think of that may have caused it, was the foam behind the channels in the steel cladding wouldve been an encapsulated application, and depending on the density of the foam used, it may have bulged it slightly.

One other option that could make it bulge, was the screw placement in the steel sheet. if it happened to be screwed in between the ribs, then it may have been able to bow the sheet out also. In hindsight, he probably shouldve installed 1 1/2" extruded foam panels in between the perlins, before the spray foam.

If he ever has to retin the side, for whatever reason, he could simply shave or rasp the foam down before applying the new steel. Its easier than it sounds.

[RoosterR]

Was it open or closed cell foam?

[BoxMN]

Thanks guys.

I am not sure on open or closed, but done the way the company who did it usually does it. I know it was to work as vapor barrier as well, so I would assume closed..?...?

He will be glad to hear that he can shave it down if needed in the future. So the foam won't "Stick" to to the tin as you pull the tin off?

[reddog]

Foam will (and should) stick if you remove the tin. Maybe 1/4- 1/2 inch

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[BoxMN]

FYI - it was closed cell.