Pole Barn...............vapor barrier?

[Maxcustody]

Talking with the builder and for condensation they recommend putting up a vapor barrier on the roof 40x60 shop. I read a previous post on here someone was going to spray foam the roof and they have to remove the vapor barrier. So my question is they want over $3000 for vapor barrier on the roof, will spray foam on the roof do the same thing? Can I get it at a reasonable cost? Thanks

 

[Hobby_Man22]

Are you heating it? I had this issue in the winter where water would drip from the cold steel purlins. I added a dehumidifier and that seemed to fix the problem. Haven't gotten to putting a vapor barrier up yet.

 

[KevinL]

I had Dripstop on my roof panels and for my 36x56 barn it added $1000 to the build. Sure has worked good so far. Guess time will tell. I do have a ceiling, and blew in a R60 of the Atticat. Can't believe how much water is running into the rain gutters every day.

 

[Maxcustody]

Are you heating it? I had this issue in the winter where water would drip from the cold steel purlins. I added a dehumidifier and that seemed to fix the problem. Haven't gotten to putting a vapor barrier up yet.

I do not plan on heating it. I have talked to a Spray foam guy and for $1000 more than the cost of vapor barrier I can get 2 inches of spray foam with an r13 value on the ceiling. Seems like a no brainer to me.................

 

[Maxcustody]

I had Dripstop on my roof panels and for my 36x56 barn it added $1000 to the build. Sure has worked good so far. Guess time will tell. I do have a ceiling, and blew in a R60 of the Atticat. Can't believe how much water is running into the rain gutters every day.

On my quote for a 40x60 they want $4300 for vapor barrier alone. Seems like an awful lot of money for some plastic..............

 

[KevinL]

On my quote for a 40x60 they want $4300 for vapor ba along rrier alone. Seems like an awful lot of money for some plastic..............

For my barn, it was $5000 more for the ceiling install and they did put 6mil plastic down (or up) as well as a combination or house wrap/vent baffles. Glad I had them put the ceiling in as I would still be trying to do it by myself.

 

[Maxcustody]

For my barn, it was $5000 more for the ceiling install and they did put 6mil plastic down (or up) as well as a combination or house wrap/vent baffles. Glad I had them put the ceiling in as I would still be trying to do it by myself.

The cost they quoted me is just the vapor barrier under the roof metal. I think in the long run I am better off with spray foam and really it is a minimal cost increase in regards to the entire project.