How is a home's foundation inspected to be safe?

I have a property under contract that was flooded a year ago:

It’s an expanded ranch built on existing foundation; basement is small and doesn’t cover the perimeter of the house.

The entire basement was flooded with water, the water reached almost exactly up to the first floor but did not rise above the first floor, meaning, there are no water lines or marks on the first floor walls.

The expanded parts of this home were built on a slab. Within the homes, there are sections of the ranch that show cracks on the wall>ceiling>wall. Almost as if that entire section is “cracked”.

It’s not THAT bad, but it’s there and very noticeable. However, I’m not sure if it’s a foundation issue. The previous owner said she had it’s been like that for the past 10 years and she has it touched up every 2 years or so when it cracks.

I would like to do a more thorough inspection/structural scan. However, every engineering company I called said they don’t do an “x-ray scan” for residential homes.

So I’m left wondering: HOW does a person verify that the foundation of a home is 100% stable? Especially considering this is an expanded ranch and the foundation is not visible from the basement.

Any input would be great…

In general, vertical cracks are “settlement cracks” that do not affect structural integrity. Horizontal cracks are generally considered structural cracks when the foundation is bulged out more than 1/4". I had a flip a few years ago that had foam insulation glued to the basement walls that hid horizontal cracks. A potential buyer’s home inspector picked up on a minute crack in a pillistar not covered by foam and the short story is I pulled the foam down and uncovered a number of horizontal cracks. I had it inspected by an engineer who used a plumb bob and ruler to measure a maximum bulge of 3/8" in this case and recommended a rod and grout repair every 2 feet along the wall. More severe bulging would require more drastic repairs.

Without access to the foundation for inspection, I don’t think there is anything an engineer can do for you. I’d be very careful about buying if there were indications of foundation failure but I was unable to inspect the foundation.

Great points.

Since this property was built on an existing foundation, and the expanded ranch was built on a slab, would you personally be concerned about vertical cracks in the house?

I’m sure the house has settled, hence the cracks, but what I don’t know is if it’s a reason to be alarmed. You mentioned ‘settlement cracks’ don’t affect structural integrity, but what’s the solution? Repair and fix the cracks every 2 years or so? What protection/piece of mind would a prospective buyer have in this situation?

Vertical cracks in the walls and ceilings of the house (NOT the foundation) could be caused by so many different things it is nearly impossible to give advise without inspecting it. Could be previous renovations that eliminated a load bearing wall incorrectly, could be termite damage causing parts of the construction to sag, could be water damage, could be undersized framing lumber, could be poor construction technique could be … settlement cracks. You’ll need to get a better idea of why it is cracking and why the previous repairs are not effective. Simply spackling over cracks rarely results in a permanent fix.

You need to hire a structural engineer. The last time I did the report cost me $175. I met him there and we chatted and have gave me a written report, which by the way saved $1500 on the price of the house.