Floor joist moisture control options
This is a two part question. First, we are building a home in East Tennessee on a crawl space foundation. We used 2×10 pressure treated wood for the floor joists. We vented the crawl space and would like to know the best way to insulate the crawl space from the house. We have a slight concern since we used pressure treated wood. We don’t know if we should use spray foam and cover the floor joists or use 1/2″ R max plus insulation board with an R value of 3.2.
Second question, as far as the subfloor our original thought was to use 5/4 pressure treated deck board in 16′ lengths so that the weather would not affect it until we frame the house, but we are concerned that the deck board would shrink causing gaps in the subfloor. Someone recommended using Advantek tongue and groove 3/4″ and the weather would not affect it prior to framing.
What are your thoughts?
Thank you
Replies
what part of e. tn?
pressure treated joist will be ok (not ideal), they will have some movement while they dry out but youll be ok. deck boards as your subfloor is not a good idea.
How long will the subfloor be exposed before the house is dryed in?
Advantech is a great subfloor and can withstand weather very well, but the manufacture guaranty on that is limited.
If you are building, then you should be in a position to pay close attention to the foundation water proofing and moisture barrier.
Spraying (closed cell) on the bottom side of your floor will be your best (and most expensive aside from encapsulating). You will not only gain the r value but you will also create a moisture/vapor barrier which will pretty much eliminate all your moisture transfer to the joist/subloor.
We are north of Chattanooga. Thanks for your feedback!