I live in Houston, worked in residential construction for over 25 Years, learned something new today. Insulation in wall cavities to be placed with vapor retarder (kraft or foil faced) facing outside of wall? Say it isn’t so…. If this is true, I’ve messed up more than just a few times. Also seen alot of others do what I thought was correct and install vapor retarder “to the conditioned” or “warm-in-winter” side. What gives? Insulation Manufacturer says “in my climate….high humidity” kraft out. Building inspector says “kraft out, house fails inspection”. He says must follow instructions on bag which states “kraft in” |
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I've heard that down south, in some areas it's a better idea to face out. But I'm no expert. If insul. co says face out for your climate, and inspector is failing it only because it's contrary to written directions, you can probably get a letter or something from insul co explaining that in your region the directions should be different.
If everything seems to be going well, you've obviously overlooked something.
Definately kraft out for climate where cooling is predominate HVAC factor. Any product rep or building assembly guru will tell you that. The rule is vapor barrier on warm side of insulation period. You will be able to get a letter from some authority to appease the building official, if they are inclined to listen. If you are doing an insulated stucco or EIFS exterior finish all bets are off though.
I'm in Pgh..where's the moisture? Inside......so VB inside the insulation....to "keep 'em seperated."
You're in Hou....I lived there too...I know the moisture is outiside...so VB on the outside of the insulation..same reason..."ya gotta keep them seperated."....
that's a great song by the way.....
Jeff
Buck Construction Pittsburgh,PA
Fine Carpentery.....While U Waite
I was told that if you're not sure, it's best to isolate the insulation from both sides. That would mean kraft out with a plastic barrier in. The idea is not to trap moisture in the insulation and thus not allowing it to lose its effectiveness.
With VB on both sides, I'd think it'd be bad. Should moisture get in, it has no way to get out. But like I said above, no expert.If everything seems to be going well, you've obviously overlooked something.
I hear you on that.
I haven't had the need as where I'm working it's always kraft in.
Check out http://www.buildingscience.com
Lots of information on moisture. And they show details for about 4 or 5 different climates.
If you want to get into it get the books.