Ceiling Insulation - Vapor barrier..

[ph1gering]

I know I have seen a lot of discussions on here, but couldn't find on thread that really helped me make the call on it..

I have a 40x40 pole barn, r19 in the walls with vapor barrier. The ceiling is already hung with metal and it over laps 4-6" at the three joints. I am going to do blown insulation up there. I live in Upstate NY cold winters warm summers. I don't plan on keeping the building 70, but i was going to try to keep the building above freezing all winter around 40ish depending on the gas bill after the first month, if its high then i'll only heat when out using it. I have 18" soffits and full ridge vent and i have but haven't installed it yet a attic fan for moisture/temp..

Should I use a vapor barrier for the ceiling? If so why?

I don't want to because I should have done it before the ceiling was hung, but was a ***** and didn't think about it. So to do it now, i would need to roll between each truss and tape etc.. going to be a real MOTHER.. But if its the right way to do it then i will..

Thanks
--Craig

 

[Gerald O]

A metal ceiling makes a great vapor barrier... if you can seal and caulk all openings seams.

 

[2CRUZ]

I have sheet rock on my walls and ceiling but I put a vapor barrier on both wall and ceiling. I don't know if it was the right thing to do or not but so far so good. It's nice and warm in there in the winter time.

 

[ph1gering]

A metal ceiling makes a great vapor barrier... if you can seal and caulk all openings seams.

That would be pretty simple to do, I could do that from above or below pretty easy.....