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Expert Q Ren Molnar Q&A Archive
Top > Insulation > Technique

Question:

Vapour barriers; what is the purpose of them? pros and cons? Code requires the barrier but could it be better without the barrier? Is it a good idea to use caulking to seal the gap where the dry wall meets the concrete floor?

Answer:

Because they're very minimum standards, codes don't mean a whole lot to me and I know very little about them because I depend of 'functionality' that, almost invariably, surpasses codes. The purpose of the VB is to keep cold from coming in direct contact with warm thereby reducing condensation. I wouldn't think of building anything without VB on the warm side of insulation. I would not seal the gap at the bottom of the drywall - in fact I would insist that the drywall be kept at least a half inch above the concrete floor.

Courtesy of Ren Molnar, Construction Consultant at HomeFocus.com. I can also be reached at (613) 748-3003 and Home Focus – The Radio Show is broadcast live 8 to 10 A.M. (Ottawa, Ont. time) on Saturdays on www.cfra.com. In the interests of retaining credibility and in fairness to all, I cannot recommend prices, people nor companies for various projects.

Answered By: Ren Molnar

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