Can anyone speak from experience about cracks in a slab foundation? I may purchase a distressed home in Southern California, the price is below market and it has not come out in the MLS listing service. The house has a long crack in the concrete slab, in the living room. It is 15 feet long, about 1/4" wide, and runs the length of the room, a foot away from the wall. Should I hire an electrical engineer to look at it before I pull the trigger? Is this common in earthquake country? Can it be remedied?
Thanks for any help on the matter.
I am not an engineer but I think you would want to have a structural, not electrical, engineer look at it. Also, i think cracks in the foundation are most often due to settling of the soil so the crack is most likely indicative of a bigger problem - I could be wrong, again I don’t know so hopefully you’ll get some other responses to help you out.
Good luck!
Thanks for your imput, and catching my silly typo.
There are 3 types of concrete slabs in construction, depending on the year the home was built and who was the builder determines which one was used.
Typically up until the mid to late 1980’s we used a conventional concrete slab with a combination of rebar and wire mesh.
Builders started using pre-tension and post-tension slabs in the mid to late 80’s or early 1990’s as a more common slab as the tensioning keeps the slab generally in one piece and prevents seperating in expansive soils.
Basically this means that in pre-tension slabs there were wires placed in the slab exposed to the concrete and the pour which were tensioned across the slab in both directions and tightened prior to pouring and finishing the concrete.
In a post-tension slab wires are placed in tubes within the concrete forms in both directions, the slab is poured and finished, then typically the slab is tightened during the curing period and the tube is filled with non-shrink grout under pressure holding the tension across the slab.
A 1/4 inch crack is within exceptable range and guidelines for any slab, and can be caused by settling of the building pad after construction.
GR
a crack means something moved.
the problem is finding out what moved, why it moved, will it move again, and what to do about it.
foundation problems are common here in the Dallas area, with clay soils that move up to 12" depending on wet/dry. under-slab water leaks are a common cause. clay dries out and shrinks, slab moves, breaks pipe, water soaks clay, clay expands, house shifts up, etc.
The usual solution here is to install piers to bedrock and set the slab on the piers. If done correctly, the house is returned to flat and level, won’t move again and problem solved (after leaks/floors/walls are fixed). Lifetime warranties are transferrable at sale. Be sure to check for cracked rafters in attic.
I live in a home with piers, and have rehabbed, rented and sold several others. I sell it as “we’ve solved this problem, so you can sleep well knowing that you’ll never have to face the expense of it yourself.”
Thank you for your input, I’m not going to worry about a simple crack-I’ll just fix it and move on…
As an update-a fellow investor who looked at this property said there were huge geological issues w/ this property. The slab crack was actually closer to 1/2" wide and after inspecting the perimeter of the property, found serious signs that the soil was unstable.