Expert: Ted Barnhill (Principal, Design45 LLC) - 1/12/2009

Question
Hi Ted,

We are building a house in MN and spent the weekend insulating the garage.  Everything was going fine until we attempted to staple the vapor barrier up on the ceiling rafters.  Being that the concrete floor isn't yet poured, the ceiling is so high that it became dangerous and pretty much impossible for us to put up the vapor barrier, at least with the ladders we had.  Before we go out and try to find 12-foot stepladders in order to accomplish this, I wanted to write you and ask... do we have any other alternatives?  Is there anything else we could do instead of the traditional vapor barrier above the sheetrock?  

Right now we are contemplating two other options:  
1) Painting BIN on the sheetrock once it is mounted on the ceiling, and  
2) using vapor barrier insulation.  
However, we've heard mixed reviews on whether either of these methods works.  

As far as how we intend to use the garage...  We would never be heating the garage throughout the entire winter, but if we had a project going on we might be heating it through a weekend or week at most.  

If you have any suggestions or feedback for us, it would be greatly appreciated!

Thanks,
Denise

Answer
Denise,

Either of your ideas would work fine.  However, I would recommend that you just put up a few staples to hold the plastic in place until sheetrocking.  If you unroll the plastic carefully, you can staple from above the rafters (or inside the trusses) and avoid awkward ladders.

By the way, there are other vapor retarding paints besides BIN that may have lower VOCs (less stinky).

If you have the budget, using foam-in-place insulation provides remarkable energy efficiency and most will act as your vapor retarder.

I hope this helps.  Good luck, Ted