How bad is too bad with foundation problems?

[Lisa Gunn]

I have been investing in real estate for 1 year and have purchased three rental houses in the Jackson, Mississippi area. I am interested in purchasing at least 3 more.  There are many properties in the area that have foundation issues due to Yazoo clay. Yazoo clay is a type of soil that moves and fluctuates. It runs in veins throughout an area so one neighborhood can have most of it's houses affected and the next neighborhood would not have it (at least so that it affects the foundations). Some realtors and other investors have tried to scare me away from any property with foundation problems saying that you can pay to fix it but it might come back. I realize that getting a structural engineer or some other professional opinion about the costs involved will be valuable information and obviously, there are different degrees of problem but how do you decide that a foundation is too bad to fix?

[Victor Evans]

@Lisa Gunn , in this particular case, the question isn't how bad the foundation is right now, but how much worse will it become due to swelling and shrinkage of the expansive clay. Clay will swell when it gets wet.. and shrink when it dries.. when these cyclical expansion and shrinkage occurs, the cracks in the slab and walls get bigger and bigger...  

If your base mat foundation was properly reinforced (engineered to account for surcharge pressure from expansive soil), the rigidity of the foundation will minimize the displacement of the structure due to vertical and horizontal movement of the clay. If the foundation was reinforced adequately, you'll only find minimal hairline cracks and minor horizontal/vertical displacement.

Pile foundations have been used successfully in the Yazoo Clay area. Pile foundation will transfer the load from the expansive clay on the surface to deeper, less expansive soil. Another advantage of a pile foundation is that the structure can be built so that only the piles are in contact with the soil and the swelling and shrinkage of the clay will not affect the structure.

So to answer your question on when a foundation is too bad to fix... watch out for poorly constructed concrete foundation and CMU walls with excessive vertical and horizontal cracks, doors and windows that do not open or shut... Just because you were able to stabilize the foundation, it doesn't mean that your building is square and plumb. If you have some photos, i'll be glad to take a look :)