Quote:
Originally Posted by Fuzz
I'd use it anyway to keep the dust out of the insulation and hold the insulation in place. Calgary gets frequent earthquakes, best to keep it secure.  |
Not a good idea. Vapor barriers serve a specific purpose, and putting them on the cold side of insulation or between two heated areas of different temperature can cause moisture to get trapped in the structure.
If you want to insulate under the floor and it's going to stay open, I wouldn't attempt any kind of vapor barrier. Just throw up some batt insulation and retain it somehow. You can do something as simple as zig zagging string or wire across, or you could staple up some kind of mesh or chicken wire, or you can buy things like these:
http://www.homedepot.com/p/Simpson-S...R100/100375163