Anyone have experience with wood foundations? Problems, success, good details? Seems like a good idea.

Wood foundations are a great idea and are easy to install. Of course it depends on the complexity of the foundation layout. I have done my last two houses with wood foundations. .60 treated wood is what you have to use, stainless or double dipped galvanized nails, 50 year sealant, 6 mil plastic and good drainage! What part of the country do you line in? Codes for installation should be in your states code book.
Wood foundations have been around for many years without any issues if installed correctly.

We know from European buildings that wood structures can last for many hundreds of years. Except for the short term cost savings, I have never been able to fathom the idea of putting a long term building on a short term foundation. Even if it doesn't have to be replaced for 50 - 100 years, it will be a major and normally unnecessary expense. If cost savings are that critical use cheap carpets or cabinets - they can be replaced easily. Or am I missing something here?

greentree;

I sold wood foundations in the mid 70's ........... never heard of any problems

My concern would be the poly used on the exterior as spc recommends (their has to be something better) and then the poly they advise over fiberglass batts on the inside, it seems like a double vapor barrier on an above grade wall. So does being underground negate the double vapor barrier or what?

Bob, I think you meant European stone lasting hundreds of years? Otherwise your post doesnt make any sense.

I'm not from termite country so I dont worry about that; no cracking; if 100 years down the road a remodel occured they might have to excavate a side and replace the sheathing, so what? And they might not, if properly built the sheathing should be isolated from the ground with a good drainage layer, it only needs to deal with indoor air and seasonal temp swings.

I like the idea of a wood foundation because a contractor could add the foundation to his realm of control in the building process, it would be faster in the building time and your ready to finish inside, no additional perimeter wall building and you can easily get a good wall r-value. You maximize your basement square footage, you can run wire through it, you can add windows easily. My concerns are the possible vapor issues and the use of that much treated lumber within a homes envelope.

My other concern which I cant do much about is the percieved inferiority of the system and loss of value when it comes time to sell.

"Bob, I think you meant European stone lasting hundreds of years? Otherwise your post doesnt make any sense. "
No, I meant above ground wood structures in Great Britain. Why doesn't this make sense? I certainly don't think these fifteenth and sixteenth century buildings sit on wood foundations.

I'm not a big fan of wood basements because eventually all wood can rot... especially wood that is in the ground surrounded by moisture. Sure you can have visqueen over the wood sheathing, back fill with stone or sand and have drains tiles, etc.. Also with the chemicals in the treated lumber, what kind of health risks are there? I sure wouldn't want my family breathing that air.

Have you looked into Superior Walls www.superiorwalls.com precast insulated concrete foundations? That is what I have in my house and love it. The entire foundation (basement walls, garage panels, and porch panels) was installed in 1 day and my rough carpenter was framing the next! The basement has 1" of rigid foam (which acts as a thermal break and gives you a R-5 insulation) between the outer concrete shell and the inner concrete studs (concrete studs are 24" o.c.). After you get your certificate of occupancy, and you want to finish your basement, you can add additional insulation between the concrete studs and hang your drywall on the wood strips that are already on the concrete studs.

Bob, it doesnt make sense because you're saying wood is long term and it is short term in the same statement and ignoring all other details.

You manage it in the same regard as you would manage it above ground, just under different conditions, and the wood is different, made for this application.

"Bob, it doesnt make sense because you're saying wood is long term and it is short term in the same statement and ignoring all other details." Wood is a long term material when kept dry and protected, short term when in contact with moisture - which is the condition any underground wood may eventually encounter. Sorry for the confusion - I thought that was obvious.

Jere is right. Wood, even pressure treated wood is not "designed" to last hundreds of years in contact with the ground. Thats why it has 15, 25, or 40 year warranties. Expecting polyethylene sheeting to last anywhere near that long and protect the wood is unrealistic. Thats also why the resale value is less - because the foundation will need to be replaced at some point.

I am not a wood advocate but, health concerns aside, the warranty is 75 years.

Even untreated wood in the northern states last much longer in direct contact with the earth due to cold winters and lack of termites

Chris
Really? Please supply the link. I was able to find warranties varying from 1 year to "limited lifetime" which lasts as long as the homeowner who did the work owns the house. Most of the warranties I saw - including "Wolmanized" which is used by some of the companies selling lumber treated to .6 levels - specifically void the warranty if used for wood foundations.

RE: our "lack of termites": the state university extension service will be relieved to know that we no longer have termites! When did that happen? Until now, we have suffered with both termites and carpenter ants, and, while the termites have been in the southern 1/3 of the state for many years, they have recently been found further north. The scientists think that is caused by climate change; maybe they just like more rural areas & better air. :)

superior walls - interesting, I haven't seen these.  If I can ask, why'd you go that route compared to a poured foundation or ICF?

What's the difference in cost?

There you go......

http://www.archchemicals.com/Fed/WOLW/Docs/Warranties/Wolmanized_PWF_Outdoor_Wood_warranty_6-09.pdf

Having come from PA. I never saw a termite until moving to Florida, I am not saying there are none, but they certainly are not prevelent as in the SE United States. The extreme cold seasonal changes is one reason they cannot be successful as in the south

jerkylips,

I went with Superior Walls (Great Lakes Superior Walls in Michigan) over poured walls and ICF for a few reasons.  The cost was about $500 more than a poured wall. I was fine with paying a little more upfront because I new when the time comes to finish the basement I will save a lot of time and money because I won't have to build 2x4 walls around the perimeter of the basement. The concrete studs have wood furring strips on the ends to nail/screw your drywall to. Superior Walls already has 1" thick rigid foam in it, which acts as a thermal break and has a R-5 insulation. Also the concrete mix is 5000 psi and they mix their own concrete in house, so they can use less water in the mix resulting in much stronger concrete. In a poured wall, you would be lucky to get 2500 psi, when you factor in the amount of time it takes the concrete truck to get from the yard to the site, they add more water to keep the concrete from setting up.  Superior Walls also offers a 15 year warranty on the foundation. No other foundation company would offer me that.

I didn't get actual estimates for ICF basement. The fact that I would have to finish the basement before the building department would issue me the certificate of occupancy was enough to turn me away. I didn't have money in my budget to finish the basement at the sametime... also I didn't want my property taxes to be based on the additional finished square footage.  The same with the poured wall, concrete mix being 2500 psi max, I felt that is where you get a lot of cracks and problems with leaks. To many variables and too many things that could go wrong if the concrete isn't vibrated enough to get air pockets out, etc.

Has anyone experienced any actual failures or done repairs?
I'm not interested in hypothetical babble or opinion.

see following

Jere,

I live about 30 miles from Detroit and my wife and I are planning on building in 12- 24 months time on some land we bought recently. Looked at PWF SIP's, got a price from Enercept, looking into ICF's and just sent a sales inquiry to Great Lakes Superior Walls in Michigan. We are both in Public service(EMS) so our pockets aren't too deep, so looking for best for the buck. You said your job came out only $500 more than poured? Were you happy with Great Lakes Superior Walls work ethic, dealings?

Really interested in Superior, just curious as to how big your basement is, wall length, height. Ours will be 176 lineal feet with 12 corners. Bout 1428 Square feet. Like the idea of the Basement SIP panel, self install however the "wood" part, not sure of. We plan on using one of the Timberframe companies out of Vermont ( a lot cheaper than MI timberframes ) and possibly Thermocore. Mostly DIY for labor. FYI, PWF quote is roughly 34K.

BTW, New to the site but have been patrolling relentlessly for information. Great stuff guys!

I own a 130 year old wooden building with wood foundations. I am sure it was not intended to last this long. We repaired with wood deigned to be buried, wrapped etc, I am sure that will last a lot longer than 130 years.

I'll be honest, it's just to scary for me. I know that I could probably (95% sure) design a wooden foundation that would survive 100+ years by doing a lot of extra work and planning, making sure everything is just perfect, and ensuring proper drainage of water away from my home. I KNOW (100%) that I can build a concrete foundation that will last 150+ years no sweat. When it comes to my house, I know what I will choose. If you are brave enough to use wood, that's great.

With the pansy chemicals they are using to treat wood today, if your waterproofing lets water in anywhere and you don't catch it quickly, you can just kiss your foundation goodbye. With concrete, while it is best to get a good waterproofing seal to prevent problems like mold, you will never have to worry about structural failure. Also you have to use all stainless steel nails and screws, which are a pain to use, because the chemical eats through regular nails. On the last house I did, we hung T-111 siding with 10 guage ring shank stainless nails. Those nails are SOFT! In all seriousness, we bent at least 75% of them, until we started pre-drilling the holes, then we only bent 10% of them. I hope I never see another stainless nail in my whole life.