Wood Basement

I will be putting a house up shortly and I have heard about wood foundations. I have done a little searching on the net and there seems to be a lot of good feedback. I was just curious if anyone has any experience or information about this?

I have never installed one in any of the houses or additions we have done. I have looked at them at various trade shows and did a little research through the lumber yards I use.
Few things of caution:
1. Dew or condensation point.
Even with protective coatings, water will always take a path of least resistance for draining. With the soil being disturbed around the foundation area, more water will tend to drain there. This keeps a higher moisture content in the ground next to the wood. Wood is still porous and the dew point is reached easier on the “thinner” wall.

Treated Lumber
All the lumber used must be rated for below grade. This is very often over looked by many people. Compared to building a deck (which has a much lessor treatment just rated for exterior), most lumber yards don’t carry lumber that has the better rating. Before you get any further on this project, I would look at the rating tags stapled to treated lumber and look them up. Then in your contract with the vendor, be sure to specifficly call out the correct treatment rating ALL the below grade lumber must have. In fact, if the building inspector is doing his/her job correctly, they will want engineering reports on it.

Strength
From the limited amount of reading I have done on the wood foundation panels, I had a couple concerns over the tests done for performance – (Structural). The compression is the force caused from pressure applied in a straight down direction. But pressure from the side will have a huge influence on the deformation of the wall. As soon as the wall is forced sideways, it no longer has the same strength as a wall that is perfectly straight up and down. Different soil types will exert different pressure loads against the wall. Clay types are nearly the worse, but the reports I read didn’t include much (if any) data on the soil types.

I walked along with a home inspector (hired by a bank) to look at a house that had a wood foundation on an addition and an attached garage. I was appalled to see how crooked the walls were, and how that translated to the above grade walls. All within industry standards, so technically, there wasn’t anything wrong. As a builder that looks at every project being my own house, I would never settle with cracked and wavy walls.

Finally, as with any products you are considering, make sure you are reading comments or performance reports that are comparable to where you are living. As an example – Geo-thermal heating and cooling can work awesome in southern WI and have a great rate of returns. However, installing that same system in sandy/rocky soil types in Wyoming could be a huge waste of money.
Hopefully this helps a little

Randy

Might b aright if YOU do not plan on keeping it longer then 20 YEARS

I seen them last longer but like said above moisture could shortin the life

Randy is right on IMHO. Just a couple of other thoughts. We built about 30-40 homes and only 1 we did with a wooden lower level but that level was only in the ground about 3 feet. If we were going with a full basement below grade we would use concrete. We poured the footings and basement slab so that the slab was 3″ higher than the footings. That way when building the wood foundation your bottom plate and 1 1/2″ of your studs would push up against the basement slab eliminating the walls being pushed in over time. One last thing, our excavator was not a big fan of wood basements he has seen too many of them cave in on the sides when back filling because of poor construction. At least that was his story. I am not a fan of them personally. I think your resale and peace of mind is worth something. IMHO

I had a listing of a wood foundation home in Iowa. The things I noticed was the basement was warmer then a concrete wall. The home inspection on the home was also good. The sellers (friends of mine) never had any complaints about it. The home was built in the late 70’s and still doing good. The negative is that a wood foundation is rare for our area affects resale value slightly.

Our family cabin has a wood basement. As was mentioned, it feels warmer and drier than a traditional block or poured basement. The cabin is elevated and in soil that drains very well. I doubt you’d want to build a wood basement in a low area or in clay. Randy’s post is exactly right on according to the research I’ve done.

Unless you are building in very sandy soil I would not consider it.

I would never own or purchase a wood basement simply due to the life of the structure being much shorter than a concrete or block basement.

If one put the same amount of research and money into drainage and insulation of a concrete basement one will have a very dry and warm basement.

Consider that most folk’s problems with moisture in concrete basements come from simply not providing adequate drainage away from the foundation, creating the condition of water sitting against the foundation and finding down along block walls to cracks and finds a path into the block or weeping. Probably the biggest sin that is made is not to provide good drainage around the base of the foundation from the start and to take extra time to seal with tar, wrap in plastic and put foam insulation around the exterior walls of a home to provide a barrier against the moisture and gain insulation value at the same time.

In contrast folks that build and own wood basements know that the same conditions will not work, so put much more pea rock below grade and establish good drainage to protect the basement as well as put in proper landscaping at the surface to divert water. In both cases, to keep the basements moisture level down, one has to create