Here’s the dilema:
I am buliding my own home and have a 12″ concrete block foundation. On the interior I have covered the block with 2″ shiplapped Celefort 300 (foamboard). Interior to this I built a 2×4 stud wall for electrical, plumbing and added insulation as it has 3 12″ of pink batt insulation. I am under the impression that the foamboard would serve as a vapour barrier as well but my building inspector feels I should cover the stud wall with a 6 mil. poly vapour barrier before the drywall! Any suggestions?, Thank-you in advance for your replies.
P.S. The outside of the block has a coating of black tar, then 1″ foamboard and covered again by Delta house wrap. ( O.K., so I went overboard, It’s my last house!)
Replies
why stop now...
put up the 6 mil...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Forget the primal scream, just ROAR!!!
it really depends more on where you live, the climate.
Hope you didn't forget the styrofoam inserts for the block cores.
Like Brownbagg said--what is the climate where you live? In other words, are you mainly concerned with heating or is air conditioning more important? If keeping the house cool is more important (and your climate has long, hot, humid summers), then the vapor barrier is best on the outside. If heating is the issue, then VB should be on inside. Are these walls below ground? If so, the outside will always be more humid than the inside and so your VB should be on outside.
You can go to a web site called "buildingsciences.com" and they will tell you all about vapor barriers for different climates and situations.
Your problem, as I see it, is that you already have about three vapor barriers! More than one can help trap moisture, and that's not good. On the other hand, the building inspector kind of holds the trump card--if he doesn't approve, then what? Sometimes you can use facts to back up your argument for your way of doing things, but the inspector may still not change his mind.
Horvath,
For all intents and purposes, climate is irrelevant in this case. If you're talking about a basement wall being insulated on the interior, here are the rules: 1. No fiberglass batts ever. 2. No poly ever. Investigate the http://www.buildingscience.com Web site long enough, and you will find information to support these rules. Convincing your inspector, however, is another story. Good luck.
While I agree that FG can cause problems in basements what is the problem with with a combination that he is using.With the drainage mat, insulation, and damp proofing on the outside I don't see any moisture coming from that direction.And with an additonal R-10 on the inside I don't see where the walls would ever get near the dewpoint.BTW, Celfort 300 is Pink Board.http://www.owenscorning.com/worldwide/admin/tempupload/pdf.3-74495-199_HighDensity_E.pdf#search=%22Celfort%20300%22