Vapor Barrier for steel building

[Evan Lentz]

Hello -

I just got a quote from an insulation company to put fiberglass batting into my steel building workshop (in the Pacific Northwest). They suggested putting just the plain fiberglass right up against the steel then putting in the vapor barrier on top of it - facing the inside of the shop.

Does that sound right? I feel like I have read different takes on that online. Will condensation occur on the steel side if done this way?

Also - the ceiling currently has a vapor barrier installed up against the steel and behind the wood purlins. They wanted to slice those out, then stuff the fiberglass in place, then put the vapor barrier on top facing into the shop. Is that a good idea? The guy said that you definitely don't want 2 vapor barriers up there, and it's better to have it shop-facing after the fiberglass.

Anyhow - just looking to see if this is the correct way to install!
Thanks

[Wayne Lomman]

That's the way it is done in steel buildings. The insulation guys know what they are doing. Cheers

[Frank Pratt]

Vapor barrier goes on the warm side, like the insulation guy says.

[Dan Rude]

Or do spray foam, which does both. That is what many do here in WI & MN. Dan

[Evan Lentz]

Or do spray foam, which does both. That is what many do here in WI & MN. Dan

Yes - I haven't gotten a spray foam quote yet. I have a 2,000 sq. ft. open space for the steel building. A fiberglass batt install on all walls and ceiling was quoted $8,000 - I was thinking that's kind of high enough to consider spray foam!

[Jim Becker]

Closed cell spray foam adds substantial rigidity to a structure, so in addition to its excellent insulation and vapor barrier properties, it can really enhance the "quality" of the space. Yes, at a price, but it's a "one shot and done" thing, too.

[Marc Jeske]

https://www.lamtec.com/technical-bul...rder-location/

http://www.greenbuildingadvisor.com/...vapor-retarder

https://www.lamtec.com/technical-bulletins/

https://www.google.com/search?q=vapo...w=1229&bih=608