[sesimmons]

I purchased a home with a crawlspace. First crawlspace I have owned and am not a huge fan. That being said, around some of the ducts where they go into the subflooring, there is staining and now that the AC is running, I see it is condensing around the subfloor.

I have read myself sick on why and crawlspace options. I realize all the debate.

However, my question is, I see that the duct funnel is sweating but the subflooring around it is, no where else. I can feel cool air coming out between the subfloor boards. If I seal this cracks between the boards and stop the cool air from coming through and where the duct goes through the floor, will that fix it?

The duct pipes are insulated well and not sweating, just the flooring around the vent entrances in the crawlspace.

Open to all suggestions. I have a vapor barrier but It needs to be improved. Thanks so much and I love to learn

 

[gregzoll]

Spray insulation would be the best way to seal the living space from the crawl.

 

[jklingel]

Is the crawl space conditioned? Where is the vapor barrier? (on the ground, or the house?)

 

[sesimmons]

The crawlspace is not conditioned. Vapor barrier is over dirt floor. I need to add some up on walls, for its just covering the dirt.

The vent that is sweating and condesing onto the subfloor is in the kithchen. I can feel cold air coming out in between sublfoor boards. Guessing this is why its condensing.

That particular vent comes out underneath kitchen drawer.

Thanks

 

[gregzoll]

You need to insulate the vent underneath for all duct work & piping. It will save you money in the long run, next to getting the flooring insulated also. As for the barrier, there are better ones out there. May have to pay a couple of kids to do the work, which would be cheaper, or get a couple of buddies & pay them in their favorite beverage to help you out.