Horizontal Crack in Foundation

Question

I was hoping to get some guidance. I recently purchased a home. During the inspection process, the inspectors put in their report that there was a hairline horizontal crack in the foundation. It was mentioned in their report, however, they told me verbally it was nothing to worry about(and I trusted them :( ), as there was no signs of shoving or spreading - so the house passed inspection. On the inside, you are not able to stick a dime in the crack, and there are no signs of water seeping in. However, upon closing, I was working around the house, and noticed that the crack is roughly the same height above the floor, and probably goes all the way around the 3 sides of the foundation(4th side is the walk out), the basement is partially finished, so I am not able to see the entire wall to know for 100% sure. On one side, the slope of the ground shows that the crack is visible from the outside. I took a level to the wall, and it SEEMED level, however I am not a contractor. The house was built in 1956, and has a poured basement(as far as I can tell). I am having an SE come look today, however I am curious if any of you have experienced this? I am worried I may have ruined my life financially by buying this house.

Any info will be appreciated. Thanks!

UPDATE: The SE came today, and didn't seem concerned, as the walls showed no signs of shoving, water, and were level. However, I have attached photos. The third photo shows epoxied cracks, and a smaller crack above. From what I understand, this epoxy would have been done 5+ years ago, and has not shown any movement judging by the epoxy. The smaller crack above does not travel any further than that photo, and I plan to epoxy that. The basement is partially finished, so I am not able to see all the way around. If I absolutely had to, I would unfinish the parts needed to make any fixes...I am considering attaching glass to the wall over the crack. That way, If the glass cracks, I know the wall is showing movement. We have got consistent heavy rain in my area recently, and no sign of water seeping through.

Answer 1

I would not be concerned at all a house built in 56 if there were problems they would have shown up long before now. The reason the crack is horizontal , my guess the foundation walls were pumped and this is the change of trucks. If you look close you may see a slight difference in the aggregate above and below the crack line. Normally we use a vibrator but I used to see contractors only use a dowel and shove down through the layers, then a hammer on the forms, a vibrates is better but things were not as automated back in the 50’s. There is rebar in the wall vertically and horizontally, depending on the soil level outside there could be steel into the foundation every 4” , may not be that much on most homes usually 6” between verticals , I just mentioned 4” because the last below grade job I did was 11’ below grade and it required 4” on center for that wall. So I would not worry, I might seal it with a latex caulking so it will be pliable and not chip out if you have extreme frost heave in the winter. But no worries it looks like a good pour.

Answer 2

No, no, no, a horizontal crack COMPLETELY THROUGH your foundation wall on 3 sides of your house is not normal and is not acceptable...especially if you’re able to stick a dime in the crack...this is not just a “hairline” crack.

I’ve designed hundreds and hundreds of concrete walls, slabs, etc. and NONE have cracked. People who have cracked foundations, slabs, etc. do not understand the difference between reinforcing rebar and temperature steel.

I suspect your problem is one of the following issues

1. lack of vertical rebar for the load
2. lack of temperature steel due to thickness of wall
3. contractor pouring a portion of the foundation wall up a ways (usually about half way) and then when they finish the pour they do not vibrate (consolidate) the two pours together by using a vibrator (contractors call it a stinger). This creates a “cold joint” between the two pours.

This allows a small “hairline” crack that can grow due to movement of the building or water penetration into the joint and then freezing and expanding, etc. (if you live in a cold climate, I suspect this is the cause of your problem.)

If the wall is still level, (smart of you to check,) I doubt if it’s a structural problem (lack of vertical rebar). and I’d definitely seal the cracks to prevent bugs, water penetrating the crack...freezing and continuing to crack the wall further.