Cracks in the wall of a house
Cracks in the wall of a house
(OP)
Hello all,
My friend’s house has a basement that is smaller than the footprint of the house. Please see attached sketch. The portion of the house beyond the basement could have been an addition added at some time in the past. A crack starts from where the basement wall is and propagates diagonally towards the backyard then horizontally to the other end then diagonally down to the basement wall. The portion of the floor where the crack is has sloped down. I told my friend that it appears there is a differential settlement which could be due to different soil capacities at the two walls or due to the big tree which is about 15 ft. from one corner has sucked the moisture out and reduced the soil bearing capacity under the shallow footing. Well, My friend hired a soil engineer who dug a couple of pits and found that the shallow foundation is a trench filled with concrete. He told my friend that the crack is due to frost action resulting from the rough surfaces of the wall and the shape that widens at the top. The tree has no role in this: he said.
What do you think? is not the sloped floor an indicator of a settlement?
My friend’s house has a basement that is smaller than the footprint of the house. Please see attached sketch. The portion of the house beyond the basement could have been an addition added at some time in the past. A crack starts from where the basement wall is and propagates diagonally towards the backyard then horizontally to the other end then diagonally down to the basement wall. The portion of the floor where the crack is has sloped down. I told my friend that it appears there is a differential settlement which could be due to different soil capacities at the two walls or due to the big tree which is about 15 ft. from one corner has sucked the moisture out and reduced the soil bearing capacity under the shallow footing. Well, My friend hired a soil engineer who dug a couple of pits and found that the shallow foundation is a trench filled with concrete. He told my friend that the crack is due to frost action resulting from the rough surfaces of the wall and the shape that widens at the top. The tree has no role in this: he said.
What do you think? is not the sloped floor an indicator of a settlement?






RE: Cracks in the wall of a house
RE: Cracks in the wall of a house
RE: Cracks in the wall of a house
RE: Cracks in the wall of a house
www.PeirceEngineering.com
RE: Cracks in the wall of a house
RE: Cracks in the wall of a house
I would suggest either underpinning the existing foundation, or using 2" diameter pipe pile driven to refusal, then releveling and re-mortaring. Option C would be to cream the addition and rebuild it the right way. Chances are that the width of the foundation is woo narrow, generating high bearing stresses. Could be real crappy soil too.
As another thought, are the roof drains tightlined or are there slash blocks near the foundation here?
Interesting how brick veneer, a non-structural element, will bridge here.
Mike McCann
MMC Engineering
http://mmcengineering.tripod.com
RE: Cracks in the wall of a house
I knew of a house that had a lot of trees in yard and it rocked and rolled - cracks often formed and/or closed up depending on rainy/dry cycles. The owner got rid of the trees for other reasons and the movement stopped.
RE: Cracks in the wall of a house
RE: Cracks in the wall of a house
RE: Cracks in the wall of a house
it's easy: it's a differential subsidence.
the frost don't it's the cause.
the tree has nothing to do.
the solution i some micropiles along the continous fundation.
they block the subsidence
bye