Wood Basement Walls & Floor

[Matt Meiser]

Anyone know anything about them? We looked at a house today that has them. Pros I see is the floor is wood over what's essentially an uncrawlable crawl space and the walls are insulated just like an above grade wall. Cons...well obviously its wood in a hole in the ground.

I've heard of them before--a builder friend of my parents did his own house that way at least 25 years ago and its still standing and they still live there. Plan to ask his wife for his number next time I see her in church.

Really liked the house, including the exterior basement access and 2 basement rooms that could be combined into one for a nice workshop space.

[Andrew Fleck]

Do you mean all the walls are studded without block or poured concrete behind them? I have never seen or heard of this before. I may be learning something new today.

[Matt Meiser]

Yes, exactly. Google tells me they are called Permanent Wood Foundations.

One other thing I should add--this home was built in 2003.

[Brad Adams]

We did the plumbing and heating in a house like that about fifteen years ago. Treated 2x8 wall studs with ground burial rated treated plywood on the outside. As I recall I think they poured concrete footings that the walls sat on.

[Moses Yoder]

What state is this in? If MI, I personally would stay away from it just because when wood is exposed to moisture without an avenue to dry it eventually rots. In a dry desert state out west it might be feasible.

[Chris Damm]

A friend of mine built a house with such a basement here in Michigan back in 1971. He still lives there and has no problems with it. The foundation is compacted pea gravel and allows for drainage. The plywood has a much higher concentration of the chemicals than the stuff you buy at a borg.

[Brian Elfert]

My uncle did this on a house around 1990 or so. Still standing as far as I know since he moved quite a few years ago. As already mentioned, the treatment for the wood is far better than typical borg treated wood.

I was planning to have a house built in 2008 and it was to be built with SIPs. Even the basement walls would be SIPs. One advantage for SIPs in a basement is they are very well insulated.

[tim morris]

Foundation grade treated material is a .60 or 60% chemical saturation. Where as most treated available today is .25 or 25%. I sold a few for a lumber yard I worked for in the early 90's. Some bases were on compacted gravel with a 2 x 10 "footing" some opted to pour a concrete footing. 2 x 8 wall usually on 16" centers with 3/4" plywood exterior and then tiled, waterproofed and pea graveled like a traditional concrete foundation. I have now been in the remodeling business for 20 years and don't understand why builders do crawlspaces that are so tight that you can't get in them. The back hoe is typically already there my rule is minimum 24" from bottom of floor joist to grade so you can get in there and work if necessary. Of course this isn't code required where I'm at so most don't think that way. It's just common sense to me. Somebody has to get in there and run duct work and insulation.

[Matt Meiser]

When I say crawl space, I mean there's gravel, vapor barrier, an air space, then a wood floor. It has a full basement and all the utilities run through that as normal.

[Matt Meiser]

Talked to the wife of the guy we know who did one. She said theirs is now 26 years old and they love it. She said we should come over and check it out and ask him more about it.

[Brian Elfert]

When I say crawl space, I mean there's gravel, vapor barrier, an air space, then a wood floor. It has a full basement and all the utilities run through that as normal.

Does this mean there is a full basement and then they used a wood floor instead of concrete in the basement? I can see some advantages to a wood floor in a basement. You could run duct work for the basement under the floor. Any time I have looked at a wood foundation they planned to use a concrete floor.

[Matt Meiser]

Wood floor too. The people we know have a concrete floor.

They ran the basement ducts in the ceiling. Probably way cheaper since they can branch off the main trunk. He said they really don't even need to open them much.