I once inspected a slab foundation of a residence for a lady who had owned a home for 15 years and was in the process of selling it. The home was about 2 years old when she purchased it from the original owner. It is located in a suburb of Dallas well known for having highly expansive clay soils. (This means that when the clays experience an increase in moisture content, they can expand significantly.)
She told me that she had a contract on the house but the buyer backed out after his general inspection reported that foundation movement had occurred. She did not understand why the inspector would come to that conclusion since, in 15 years, she had not had any sheetrock cracks, brick cracks (except for one minor crack) nor experienced any problem with any of the doors.
My investigation showed that the foundation was over 6” out of level and I concluded that the back of the foundation had heaved upward because of soil expansion. Furthermore, all of this occurred prior to her buying the home.
I suspect that the original owner knew about the problem and made cosmetic repairs and dumped the property. Unfortunately, when she bought the home (15 year ago), her general inspector did not warn her about the condition of the foundation.
The good news was that there had not been any significant foundation movement since she purchased the house; the bad news was that prior to her purchasing the home, it had heaved upwards and was 6” out of level.
If a problem with a foundation is defined as it being significantly out of level because of upheaval, then the logical remedy would be to lower the heaved portion. This can be done, but it is outrageously expensive and is therefore done infrequently. Because of the expense, this was not an option for her.
However, if a foundation problem is defined as having recent foundation instability, then she was in good shape because the home had not moved noticeably for 15 years. However, the big problem was that the foundation was over 6” out of level.
There was no financially reasonable remedy for solving her foundation problem. So, because the seller had covered up defects and she was not properly advised when she purchased the home, she was stuck with a nice home in a nice neighborhood that she could not sell at the going market value.
In a defense of her general inspector, the original seller of this home had the cosmetic damages repaired prior to putting the home on the market. If a seller of a home hires a professional painter and brick mason, they can make most defects in the sheetrock and brick disappear. And if a general inspector does not see cosmetic defects normally associated with foundation movement, they (at least some of them) assume that the foundation is ok.
So, could this have been prevented? Yes. The key is to either hire a very detailed general inspector who can look beyond the obvious (and possibly a structural engineer that will take slab elevations).
When she purchased the home, her general inspector (and her realtor) should have noticed the slab diselevation (I do not know how they missed noticing that the master bath was over 2” out of level). Nor did they notice that the kitchen base cabinets, the hall bathtub, the fireplace hearth and the fireplace mantle were all noticeably out of level.
To repeat, a buyer’s first line of defense against buying a house with a damaged foundation is to hire a competent, detailed-oriented general inspector. If there are indications of unusual foundation movement, he may recommend hiring an engineer to do a more detailed inspection of the foundation.