insulation with no vapor barrier

[Bob Slater]

I have a 12 foot section of wall with drywall and no insulation in my shop. Behind it is a brick wall (Two layers) then an air gap of about 6 inches with the building next to mine. Air doesn't really circulate behind here in terms of wind blowing, but there is no complete seal between the buildings. I was thinking of blowing in loose insulation in this cavity, but wonder if it is worth it? since the wall is not directly exposed to the outside. Putting a vapor barrier in would mean taking down the drywall and I have no appetite left for drywall work.. Can you get away without a vapor barrier or will mold set in? I suppose I can always do nothing. The acoustics of this wall really bugs me too, as it adds to the echo in the room.

[Duane McGuire]

I believe that a vapor barrier is less important in a shop than in a house. Houses produce a lot of moisture from bathing and cooking. Shops generally do not. To make life simple, but still repecting the potential need and problem, I'd go ahead and blow in the insulation, then paint with a vapor barrier paint ... not as effective as sheeting, but ... no drywall work!

Here's some references:
http://www.fpl.fs.fed.us/documnts/fplrp/fplrp319.pdf
http://www.amesresearch.com/app_vb.htm

[Bob Slater]

Excellent slice of information there, thanks. I somehow have a feeling that the paint store guy will give me a blank look when I ask if he has any aluminum paint!

[Jim Becker]

Bob, I think you'll be fine with filling that particular wall with insulation without installing a formal vapor barrier.

[Bob Wingard]

Go to a Glidden store, and ask for .. .. ..

Ultra-Hide Vapor Barrier, product: 1060-1200

Formerly known as InsulAid. I used it in a house mny years ago .. but didn't really have an effective way to measure it's performance.