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Cracked foundation five days after pour

Weatherlite

Registered User
Joined
May 14, 2018
Messages
13
Location
Mountain Home Idaho
I'm having a home built by a very reputable builder. I'm one of those people who continually checks the job site...both to make sure things are done pee the plan, and just to get pictures to share with family and friends Saturday, I was taking a look and found two cracks.

One crack on the garage outer wall side and the other on the opposite side of the house. Both go completely through the foundation wall and footer, mostly in a straightish line. Not diagonal or horizontal. Each crack about 1/8" wide. I reported it to my realtor, who brought it up to the builder this morning. Waiting for them to inspect and tell me what's going on. Today after work, I went to get more pictures and video and I found a third crack which definitely wasn't there Saturday! This one is in the inner garage wall. All three cracks are within four feet of each other distance wise from the front of the house, almost as if a great weight was pushing down on the front of the foundation and it broke right across the center.

Other than the fill for the garage floor there is nothing else done. No wood attached yet. Nothing. To me, this seems SEVERELY messed up!! I could see a crack appearing years after, but not before the house is even built. I'm praying the builder tears it out and starts over, but I'm not holding out hope for that either.

So, what's the concensus? Would it be wrong to build on a known cracked foundation? Is it common? Any insight is appreciated.
 
A general rule is "all concrete cracks", I testified to that once and reappeared in front of the same judge many years later, when she saw me she stated "The one thing I've always remembered that you taught me was that all concrete cracks".

That being said, attach some pictures of the cracks and we can probably tell you whether they look like a problem or not. At least two pictures, a macro of a crack, and an overall picture of the area, settlement cracks are a problem, drying cracks are generally not a problem.
 
Since you are paying a little money for this

Hire a structural engineer to look at the design and pour
 
Cracks didn't appear until after the garage was filled and packed Dump truck tracks show it backed up onto the front wall of the garage. Could that have done it?

Also, these are the best pics for now. Do you need really close close-ups?
 
Cracks didn't appear until after the garage was filled and packed Dump truck tracks show it backed up onto the front wall of the garage. Could that have done it?

Also, these are the best pics for now. Do you need really close close-ups?

No, it appears that they may be settlement cracks from improper compaction, ask your builder for a copy of the soils report, then call the geotech that performed the soils report and pay him to look at it, yes it does appear that you may have a problem, improper compaction is always a problem.
 
If this was virgin ground I'm going to guess there wasn't any soils report or compaction testing done prior to this pour. Probably wasn't required, either. Residential construction in other parts of the country is not like it is in California..

I'm not there so I can't tell you for sure, but I'd bet decent money they broke it when they backed the truck in - if all the cracks are on one or two walls and within ~4' of each other like you say, either they put too much weight on it too soon or they poured it over a really soft spot that they didn't/couldn't see.

Whatever caused it, if I was paying for it I'd make them fix it.
 
Though not a cause of the cracking, with a all those surface voids you can tell it was not vibrated very well.
 
If this was virgin ground I'm going to guess there wasn't any soils report or compaction testing done prior to this pour. Probably wasn't required, either. Residential construction in other parts of the country is not like it is in California..

I'm not there so I can't tell you for sure, but I'd bet decent money they broke it when they backed the truck in - if all the cracks are on one or two walls and within ~4' of each other like you say, either they put too much weight on it too soon or they poured it over a really soft spot that they didn't/couldn't see.

Whatever caused it, if I was paying for it I'd make them fix it.
I require test borings at all outside corners of a home, code or not is not the issue, minimum building practices require proper compaction, if it was caused by the truck the ground wasn't properly compacted for the foundation to crack.

You do bring up a question though, where is this subdivision located? Since the OP is carefully observing construction maybe he can tell us, was all topsoil stripped and stockpiled and is the foundation built on existing soil under the topsoil or was compactable soil imported? We had a situation about 15 years ago in Texas where there was an organization of homeowners fighting a major builder, there were only two test borings for the entire subdivision and homes they were living in were settling all over the place.
 
I agree it could be compaction due to the crack in the wall and down to the footing. Back filling green concrete for sure can crack the wall. Big rocks or a concentrated bucket or dump truck load of soil dumped in the garage cavity can bump the green concrete causing a vertical crack.

Noticed the foundation guys wet set the anchor bolts (ICE), and that there appears to be no portal hole straps attached to the foundation for the garage opening. Maybe using another way to get the portal hole framing passed. Simpson strong-tie maybe?
 
IMO, sounds and looks to be due to loads imposed on green concrete. The dump truck or piece of equipment they used to back fill most likely done the damage. I would go with the truck since the footing is crack also.

with a all those surface voids you can tell it was not vibrated very well.

I have also seen it look like that when over vibrated.
 
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When I hear "reputable builder" I take it with a grain of salt. It may just mean that the person saying so did not have any problems.

Have an engineer look at the problem. As a minimum this will give you some piece of mind and might send a message to the builder to clean up his act.

I agree that there could be problems associated with lack of a geotechnical report, poor compaction, and truck placing load on relatively green concrete. It would not surprise me if you are seeing some shrinkage cracks that are the result of putting too much water in the concrete. This may include the vertical cracks in the grade beams.

While all concrete ultimately cracks these early cracks may be telling you something. Have an engineer look at the issue
 
I think the concrete truck is supposed to keep track of the water added to the mix?
 
Is there reinforcing bars in the footings and stem wall?

Though not a cause of the cracking, with a all those surface voids you can tell it was not vibrated very well.

I couldn't get a picture because I was at work, but yes. there is rebar in there, not just the bolts.

If this was virgin ground I'm going to guess there wasn't any soils report or compaction testing done prior to this pour. Probably wasn't required, either. Residential construction in other parts of the country is not like it is in California..

You do bring up a question though, where is this subdivision located? Since the OP is carefully observing construction maybe he can tell us, was all topsoil stripped and stockpiled and is the foundation built on existing soil under the topsoil or was compactable soil imported? We had a situation about 15 years ago in Texas where there was an organization of homeowners fighting a major builder, there were only two test borings for the entire subdivision and homes they were living in were settling all over the place.

It's not virgin ground. (assuming you mean something like a plot of land I just bought with no prep for the build) It's in a subdivision which had the entire area leveled, graded, compacted, etc (I don't know the technical terms), and then they threw a few feet of topsoil on. Basically, the whole area was supposedly properly prepped. This was done about 15 years ago. I can't say for sure how they did it, but from the soil I have seen around here, they probably didn't have to bring in much to compact. You dig down 2-3 feet anywhere in this area and you may as well be digging through concrete. It's a fine volcanic soil which has pretty much solidified over the years. Anyway, for my build they stripped the topsoil leaving half on scene and hauling off the other half. The half left is for grading the overall lot after the fact. They compacted the entire area after, just to be sure it had not loosened up since it was originally done. As for test borings and soil samples, I'm having my realtor check into that.
 
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