Does anyone know what causes all four corners of a concrete foundation to crack in triangular pieces? I am looking at buying a Cape Cod that was built in the 50s and this is the case with the foundation. The corners have been patched, but each one is cracked with the base of the triangle near the top of the foundation and the crack coming to a point at the corner. The house is in a cold climate.
Thank you,
Carissa
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Replies
Walkout basement or crawlspace?
PAHS Designer/Builder- Bury it!
The house has a full basement with outdoor access.
The house has a full basement with outdoor access.
With one wall completely buried and the opposing wall exposed? Cracks are on the side walls?
That's very common here and I was excited when a structural engineer clued me in. Insufficient footings and/or wall-footing connection. Both walls lean a little to the exposed area. The side walls try to keep them plumb but aren't able. That parallel cracking is normal. Houses aren't generally falling over, but it sure doesn't make one feel good. I've seen 5-6 repair lines on occasion, meaning it was continuing to lean.
I live in a house, similar to your basement, with one exposed wall, opposing buried wall has 15' of dirt against it. No cracking on the side walls, but you wouldn't believe my footing under the buried wall. The engineer knew what he was talking about.PAHS Designer/Builder- Bury it!
Yep. My house has that condition, as do most houses in this area. House was built in 1993, concrete slab on grade with wood framing and brick veneer. It came with a HO warranty (which has proven to be pretty worthless), so we filed a claim when we found the problem. They sent an engineer out to loook at the problem and write a report that vindicated the builder and the warrantee company. He said its a normal condition caused by the foundation and the brick shifting slightly, and the pressure from the brick causes the corner to spall off. Perfectly normal, he said. All cosmetic, not structural issue. Could have been prevented by adding a slip sheet under the brick at the corner. We are saving the 'official' letter to show the buyer if we ever have to sell.
Whenever you are asked if you can do a job, tell'em "Certainly, I can!" Then get busy and find out how to do it. T. Roosevelt
This house has a full basement. It doesn't look fatal. I think it probably is normal because it's happening at my parent's house too. Good idea to save the letter though.
Thanks for the info.
Some foundation cracks are not terribly significant, others can be your first clue to an expensive repair.
How wide are the cracks?
Is there any indication that they are still getting wider?
What type of soil is the house built on?
Is there a seasonal water table?
Is there any indication of structural problems above the foundation?
What angle is this "triangle" you described?
Generally, how does the concrete look (other than being cracked)?
Are there any horizontal cracks anywhere?
It would be worth every dime to hire a structural engineer to look at this if you are seriously considering this purchase.
DRC
Those are a lot of questions I can't answer. Hopefully, I can give appropriate answers to some. The ones I can are:
There are no horizontal cracks.
All of the other concrete looks good.
I would say that it is an isosceles triangle or pretty close.
The brick above the concrete looks good. There is one very small area at the top of the first level that could use some tuck pointing.
The house is in Illinois, so the soil isn't sandy or rocky.
Thanks for the suggestion.
Hairline cracks in the foundation come from movement, most generally settling but pressure from the backfill can also crack the concrete. If the cracks aren't leaking, don't worry too much. Are there working gutters on the house and drain pipes that dump the water away from the foundation? The rather substantial amount of water that washes off a roof and drains into the ground around the house accumulates. Some soils will collect this water and will expand when frozen, others will wash and undermine areas under the footings. If the cracks leak, you will have to patch them from the outside. Most likely it is just settlement that has occurred over time. Concrete won't bend so, if your long walls settled a bit and the corners stood strong you will get cracks.
Beat it to fit / Paint it to match
Thank you!
A picture might be worth a great deal here.
Where are you at in Illinois?But they that wait upon the Lord shall renew their strength; they shall mount up with wings as EAGLES; they shall run and not be weary; and they shall walk, and not faint. [Isaiah 40:31]
A picture might take me a while.
I am in the Chicago area.
If it's a brick house, Ed Hilton has the right answer. We use 6 mil poly(Texas) between the brick and brickledge to prevent this condition. The heat/cold cycle causes expansion of the brick. If the brick wall is mortared to the corner, the corner moves with the mass of the brick wall. So Engineers say.
Something like this?
Whenever you are asked if you can do a job, tell'em "Certainly, I can!" Then get busy and find out how to do it. T. Roosevelt