As discussed previously, foundation sales personnel make some pretty outrageous claims and unfortunately, most are made verbally where they cannot be verified, or held accountable for.
In addition, there is no governing ethics board to keep the conduct of these people accountable. The key tool to hold these people accountable is to always get them in writing. Then you can do your own research to verify them. Today, I would like bring to light another of such outrageous claims.
Claim: If you repair the crack in your stem wall you can eliminate foundation heave or settlement. This is a ridiculous claim that has no backing to it. Repairs to stem wall cracks will have a negligible effect on both foundation settlement and floor slab heave.
Let’s talk about settlement first. Most cracks in stem walls are a result of rusting rebar. Most of them are above the outside soil level…… So let’s assume that that the water level rises up to the level of the crack, a pretty rare occurrence….maybe once or twice per year for a few hours. Not much volume. The overwhelming majority of these cracks do not penetrate all of the way to the back side… again maybe some water might get in…. but not much.
The footings are 2 feet below the stem wall crack. In order for the water to affect the footing, it must get the soil underneath it. The amount of water that gets to those soils from the soil directly on top of it as opposed to entering the crack and then soaking down 2 feet on the inside of the stem wall is comparable to few drops to a bathtub. Repairing the crack with have a negligible effect.
How about heave? Again, the amount penetrating through the crack as opposed to the soil below it is similar to the above paragraph.
95% of the problem we see with slab heave is a dome heave where the center of slab has risen higher than the edges. Any attempt to arrest moisture that is coming in from the edges is good in the long run. It takes 20 years for dome heaves to manifest themselves…… 20 years to accumulate more moisture in the center than there is on the edges. By drying out the edges in the first several years, the differences in moisture from the edge to the middle will increase…. Making the heave problem worse. For many years until it equalizes.
Repairing a crack in stem wall will not stop enough moisture to affect either footing settlement or floor slab heave. Nor will it affect any other way other than rusting and deterioration, as explained in my upcoming blog.
The only cost effective and scientifically documented way to affect the moisture in the middle areas of the slab is to install our patented <p>MoistureLevel Smart Foundation System.</p>