Permanent Wood Foundation
We are adding a one-story addition (22’x30′) onto our existing one-story ranch. The builder has indicated that he will give us a $1,000 discount if we will allow him to install a “Permanent Wood Foundation” instead of a conventional cement foundation with blocks.
We are not putting in a basement and would not appreciate any results such as: lack of dampness and ease of finishing which he indicates are advantages to this type of new foundation. He will, however, allow us the discount in order to promote this type of foundation in the area. The $1,000 discount is very attractive.
Should we opt for this type of foundation? What are the disadvantages? What problems could arrive in the future if we opt for this? Your expertise would be most appreciated.
While all of this may be true, there are, in our estimation, some major drawbacks with the Permanent Wood Foundation. The first is life span. Assuming proper construction, protection and maintenance, a concrete or block foundation will far outlast a wood structure. Although, concrete is susceptible to movement and occasional cracking via hydrostatic pressure, it is not nearly as vulnerable to damage due to water and other structural pests as is wood. Even pressure-treated wood will deteriorate in time and with prolonged exposure to dampness.
Some environmental groups also have trouble with the Permanent Wood Foundations. They fear that the wood-preserving pesticides contained in this material will leach into the soil and hence the groundwater system, tainting both and resulting in potentially serious health hazards.
Where dampness is a problem, a properly installed, waterproofed and ventilated concrete or block foundation will provide the greatest level of ongoing protection. Whereas a wood foundation makes finishing the interior of a basement a bit easier, the same condition can be achieved by installing a 2″x4″ stud wall in front of the interior face of the concrete or block foundation.
This stud wall will make the space easier to finish by allowing you to run electrical and plumbing in the wall. It will also make the space more comfortable by providing a cavity for the installation of some insulation.
While it’s true that for finished basements the stud wall is added expense, we believe that the drawbacks associated with a Permanent Wood Foundation make the traditional concrete or block the preferred choice. Spend the extra $1,000 now, rather than several thousand in repairs later. Remember, a home is only as good as the foundation that it rests upon.