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covering wood foundation below siding

jcev's picture

Our new home has a wood foundation.  The siding (fiber cement) will be going on soon.  What can we use to cover the foundation between the siding and the ground?  It has to look decent, stand up to an occasional scrape by a snow shovel and not cost an arm and a leg.

-plain treated plywood = too plain

-color coated aluminum roll stock = too fragile

-"Groundbreaker", a fiber reinforced roll stock product only comes in shiny light gray-unacceptable look.

Any suggestions?

(post #90826, reply #1 of 17)

Can someone enlighten me as to why homes in America still have wood foundations?

Mike O.

(post #90826, reply #2 of 17)

Because they're cheaper than concrete and the builders will be retired before they rot.

(post #90826, reply #3 of 17)

I could be wrong, but I don't even think they are allowed here in New England/NY.

Mike O.

(post #90826, reply #4 of 17)

Given both proper site conditions and construction a wood foundation can last indefinitely.  One advantage to them is easier finishing of the inner foundation walls...Would help to know exactly what you are trying to cover...



(post #90826, reply #5 of 17)

The foundation is covered with 10 mil plastic from the top plate down.  We need a hard covering to protect the plastic in the area that is above grade and below the siding.   Thanks.

(post #90826, reply #6 of 17)

JCEV:<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

Assuming you have something like 5/8" foundation grade plywood underlying the poly.  The area you are referring to is normally covered by a "grade" or "backfill" board.  This board extends from the bottom of siding to @ 6 inches below grade.  Typical specs are 1”x12”x12 syp. 60 #2. The wood needs to be treated to a minimum concentration of .60 lbs CCA per cubic ft of wood. Hopefully one of the painting pros will be along to assist with best way to stain/paint same so it goes well with your siding.

Hope this helps, and good luck on your new home;



(post #90826, reply #7 of 17)

About the only site I would choose that material for is in desert sand in Pima, AZ where it never, ever rains.

I don't even like block foundations.

Mike O.

(post #90826, reply #9 of 17)


I was just trying to keep in mind how the original posting started: Our new home has a wood foundation... In most cases is a poured foundation superior? probably.  But in this case the foundation's built, it's wood, and it's under their new house...



(post #90826, reply #10 of 17)

I'd rather have a wood foundation, properly done than a block foundation.


Excellence is its own reward!



Oh Well,

We did the best we could...

(post #90826, reply #12 of 17)


I'd rather have a wood foundation, properly done than a block foundation.

Can you elaborate as to why? I'm sure you've just been itching for someone to ask.

(post #90826, reply #13 of 17)


A.) moisture penetration of the envelope depemds on the membrane and methods used for drainage and not on the wall material itself.

B.) in the soils I work with, block walls are renowned for breaking up and failing. two of my first construction jobs involve dbeing the guy on the shovel to dig clean and repair a failed block wall. I've done several since and always wondered why paople would want a bunch of individual CMUs for a wall instead of a wall system. My own opinion is that a well built wood wall will have move strength than block and have less likely hood of failing in a fifty year period.

C.) because it is easier to insulate and run wiring

D.) because I am a carpenter rather than mason and masons are hardeer to find in this locale'.

but if I can get a poured, re-inforced wall on a good footer, that's my first choice.

No, I wasn't etching - I offer my opinion, because it is, not to stir up argument. I'd already forgatten this thread.


Excellence is its own reward!



Oh Well,

We did the best we could...

(post #90826, reply #14 of 17)

Wasn't infering you would look to stir up an argument.  Quite the opposite actually. You are usually so thoughtful and thorough with your posts, I found it surprising to see the one sentence post about a subject that could easily turn into an argumentitive one.

PS  I like the wood foundation idea for most of the reasons you specified, but the huge drawback in my mind would be saleability. It is just not that accepted and proven a practice to sell to the general public. Block foundations, they've seen and dealt with them for a long time now.

(post #90826, reply #15 of 17)

"huge drawback in my mind would be saleability"

It's all a matter of percieved value.


Excellence is its own reward!



Oh Well,

We did the best we could...

(post #90826, reply #8 of 17)

Screw some durock or other ext. rated cement board to the foundation and parge with coat or two of one of those Foundation coatings.

I can't recall any specific names, but your masonry supply house will have them.

Read and FOLLOW the directions!

Substitute Acryl 60 or whatever the manufacturer reccomends for some of the water in the mix.

This will be alot of work, but thats what it takes, so you don't mind do you?

Mr T

Do not try this at home!

I am a trained professional!

. .

(post #90826, reply #11 of 17)

It sounds like this is already backfilled, which is too bad. Planning should always be completed before beginning the project and it's too late to turn back. You have a plastic bag protectinng your foundation for the next ________however long you live there.

I would be for troweling on an elastomeric that looks like concrete but obviously, it won't stick to the plastic bag. That leaves you with the more expensive task of screwing on the cement board and parge coating it, or a foam board and dryvit type material.

If you put coil stock on, how long do you suppose it will be before the bottom edge of it scrapes a tear in the plastic bag and lets water in?


Excellence is its own reward!



Oh Well,

We did the best we could...

What did you end up doing (post #90826, reply #16 of 17)

What did you end up doing with this?  I'm looking to do something similiar as well.  I currently have pressure treated plywood covering between siding and soil currently but it doesn't look the greatest.  It doesn't appear Groundbreaker has changed much in the last 14 years.

help (post #90826, reply #17 of 17)

I know this is old. However, I am looking into buying a house with a wood foundation house.  I wouldn't even be here had I realized it was wood before I agreed to buy it. I still have to have an inspection for it. Anyways, I was wondering what your thoughts on wood foundations were again now that it has been a few years. It is in an area that is in close proximity to a lake. It doesn't sit on the lake but not far from it. It would have lake "access". I am just worried about rot issues with moister. And we don't plan to live here forever and we would like to maintain our (in reality exceed) our current buyer price. It does need work on the inside and out. So we were hoping to do this and try to move shortly after. It's in a good location but the wood foundation.... it just doesn't appeal to me and I don't know that it would appeal to many other buyers.  Which makes me question, is the resale value really there. Is there a way to help extra protect the wood foundation?