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I have a 2 story garage with the rear being cinder/concrete block walls.

I just noticed this crack. Havnt lived here that long so not sure how long its been there

Is this something to be concerned about?

enter image description here

isherwood
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Sjpson
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2 Answers2

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Yes, you should be concerned. Cracking like this is caused by movement (the structure has moved, such as settled) and this type of cracking is unusual. This needs to be reviewed in person by a structural engineer who can look at the particulars of your situation. This is not something that you can get a good answer for here on this or other sites.

FWIW, I'm a structural engineer. I'd be interested in what they have to say about it

Ack
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    As a structural engineer, what do you make of the apparent fact that the crack neither extends downwards or upwards through additional courses of block? – J D Aug 10 '20 at 14:33
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    That is an interesting observation. I wonder if a vehicle in the garage drove into the wall and caused the cracks? – Steve Wellens Aug 10 '20 at 14:41
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    This is a comment not really an answer. – DMoore Aug 10 '20 at 15:06
  • @JD In simple terms, it hasn't 'needed' or 'wanted' to. Being a little more detailed, it's more of a localized situation and it cracked where the CMU (cider block) could no longer carry the load – Ack Aug 10 '20 at 17:36
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    @Ack I understand it's a localized stress manifesting in the CMUs, but I was wondering as an engineer, if there were common causes. For instance, let's say the footing was poured w/o rebar and the whole foundation was cracked, and that ran up vertically, then it's an obvious cause. I thought it might be common if rebar between courses was omitted, or the joists were anchored in the walls, let's say the cell was filled w/o vertical rebar. My thought might be compression from the roofing transfering down the corner given a lack of reinforcement. – J D Aug 10 '20 at 18:16
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    @JD not common to the point that I myself will be interested in the answer. I have educated guesses based on my knowledge and experience but I would need to be onsite to tweak out the particulars. More directly to your questions: this crack is likely more related to a horizontal force than a vertical one. If it's related to the foundation, then I would expect the issue to be located more at the far corner which cases the wood wall to rotate and want to pull away. It's possible that the CMU is reinforced and the anchor only placed in the face, though unlikely to cause multicourse cracking – Ack Aug 10 '20 at 20:59
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Being a corner and a mid block crack I would say yes there is an issue here. It could be the attached building footing sinking but mid block cracks are really bad I have only seen them in walls that were not properly filled, or some that were not filled at all. But a mid block fracture over this many layers or courses needs a engineering review and proactive repair before major structural failure.

StayOnTarget
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Ed Beal
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  • Would a foundation specialist be the kind of person I should be contacting? – Sjpson Aug 09 '20 at 18:59
  • I would want a foundation pro on this one , if you are in earthquake country it could be from a tremor but most the mid block fractures I have worked with were more involved than a general contractor could handle. I have used and recommend ram jack if you have them in your area. they do stop and reverse some damage but the cause needs to be evaluated if it is compaction, or erosion, or from an earthquake. – Ed Beal Aug 10 '20 at 01:12
  • Southern Minnesota here, no earthquakes. Have read it could be drought related, thoughts ? – Sjpson Aug 10 '20 at 02:25
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    @Sjpson droughts won't cause cracking directly, but dry weather could cause ground shrinkage/sinkage. If part of your building moves and the other part doesn't, something's going to give. – Criggie Aug 10 '20 at 03:46
  • Drought can play havoc with ground water and cause movement but I live in an area with a shallow water table and earthquakes. I don’t see any attempts of repair how old is the building? And additions or modifications recently? – Ed Beal Aug 10 '20 at 04:40
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    As far as I am aware it is original to the property, so 70s would be original build. Have not built onto it at all – Sjpson Aug 10 '20 at 11:54
  • With this being a newer issue I would want a review by a foundation pro. Minnesota may not have the issues we see on the west coast. A drought could end up being the cause, since you live in a stable region your blocks may not be backfilled or only every other or a case like that and that could explain the mid block cracking. – Ed Beal Aug 10 '20 at 13:23
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    This could very well not be a foundation/settlement issue. The force that is causing the cracking is perpendicular to the block and right where the roof is attached. Wood moves a lot more than CMU (cinder block) and my guess is that the issue is lack of accounting for differential movement at the connection. Get a local structural engineer to look at it please – Ack Aug 10 '20 at 17:39
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    Yes it could be stress from that structure but my guess the block is not filled or reenforced so any settling from water table changes could be the root issue. – Ed Beal Aug 10 '20 at 19:40
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    CMU doesn't need to be fully filled and reinforced. While the CMU is showing failure it might not be the problem rather just a symptom. You suggest that it's the foundation and further suggest that the root cause changes in the water table (very bold of you, I'm curious how close you are). No matter the cause, if it's the foundation, it's the foundation. Don't blame the poor CMU without just cause! – Ack Aug 10 '20 at 21:07
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    40 years of construction experience block just don’t start breaking unless improper footings or a wall that is not reenforced and I was following up on a comment the op made I would expect an engineer to weigh all the facts and variables. – Ed Beal Aug 10 '20 at 21:20
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    Not an engineer, but I spent a few years breaking things under the direction of one. That crack doesn't look like a foundation-settling crack, or at least not directly. It looks like something's pulling that section of the wall sideways. – Mark Aug 11 '20 at 00:02