Spray foam in the crawlspace?

[DustynF]

I am getting ready to put a vapor barrier down in the crawlspace this weekend and so it will be totally sealed from moisture. I have rigid foam board on the concrete walls and then I will be covering the floor and the walls with a 12 mil vapor barrier. I was wondering what everyone’s opinion is on insulating between the floor joists. The options that I was thinking about is un faced fiberglass or closed cell spray foam. I have been told that spray foam doesn't allow for termite inspections and sometimes moisture can build up behind it. Not sure what to believe. I would like to go spray foam because it will be easy to totally seal the floor joists. Thoughts?

 

[Highbeam]

Supposedly, you don't need to insulate the floor since your crawlspace is of the non-ventilated and insulated type.

 

[DustynF]

I should have explained myself a little better. I wanted to insulate above the sill plate on the exterior walls between the joists. I have read some people say its bad and others say its good.

 

[WVBrady]

I bought a house that had experienced one winter. The crawl space was not insulated. The block walls extend about 12 inches above the ground on the outside. The exterior 2x12's had water stains from condensation. The interior runs about 60 F in the winter with exterior temps from the teens to the thirties. I tucked fiberglass batts against them with the vapor barrier to the inside. They have since dried out and remain that way. I also insulated the walls with fiberglass batts encapsulated in plastic.

There was also a small utility room that had a connection to the crawl space that I was not a aware of. When I built a garage adjoining the house 5 or 6 years later, I found that the exterior 2x12 was completely rotten.