I just build a new house this summer of 2003. I put R-19 insulation in the I call the rim joice ( the area where the floor joice attached to the outside wall). Everything been fine until our Minnesota winters got into full swing..I noticed that the insulation was stuck to the joice because of frost in spots and others there was moisture and mold delveloping..

We do have and HRV unit for air circulation and run a dehumidfier even..

I never heard of putting vapor barrier in this area but that is the only thing I can think of..

Please give me some input.

I also found moisture on the rim joist as well as the sill plate. The home is about thirty five years old . Could plastic vapor barriers on the inside wall cause this? If they are there and this is the problem what is the fix? The strange thing is the moisture is closer to the corners and not at all in the middle of the walls. Our weather in southwest Missouri has been a roller coaster up and down this year could this be a cause?

Plastic on the inside walls create a moisture chamber. If you have moisture barriers on the outside.

You need to supply more information before we can help.

Is this a conditioned basement or crawlspace?
A vented, unconciditioned crawlspace?
Other?

Generally speaking an R-19 is far below minimum code requirements for sidwalls in Minnesota winters and could be the main reason why you have frost.