Have any of you inspected a home with a permanent wood foundation? What are your thoughts on this type of foundation and what are some of the most common defects you have seen associated with this type of foundation?
Biggest problem I find is that they are not designed or built properly for the site and, consequently, are failing in some way…bowed studs and walls, especially evident at the top plate/floor joists connection, leaking moisture, improper backfill, etc.
I’ve seen them where the gable walls were so bowed in that the center beam was sticking out past the previous wall plane.
Definitely find out whose design criteria /instructions they used, was it an engineered plan or did they just do it themselves with out professional help such as an experienced PWF builder. I’ve worked on 20-22 over the years and only one had a bowed wall from the excavation contractor improperly backfilling…happens with concrete/block also.
Oh, I’ve built many, too, Brian but it is usually the home of the do-it-yourselfer that did what his uncle, the plumber, said because he saw one built once. :roll:
One of my concerns is the effect of water on this type of foundation. In my area we have a high water table and the home I am concerned about has a sump pump installed. Obviously the inspection is limited in terms of knowing if gravel, sand and polyethylene were used/installed properly.
Don’t forget that if you have a high water table, poor backfill and poor perimeter and footing drainage, you will have problems with concrete/block foundations also.
If the builder did not use concrete footings on undisturbed/compacted soil, the whole footprint of the house plus 2 feet out should’ve had at least 5-6 inches of crushed stone installed as a base for the wood footing plates and basement floor/slab. This allows for great drainage for the whole foundation/basement…so much so that up here in Canada you do not need foundation perimeter tiles using this technique (had quite a fight with a town inspector about this in 1987…and won!!) but would need the perimeter tiles with a concrete footing. Only tile/piping needed is when taking soil water away to a storm sewer or other approved open drainage.