Horizontal crack in foundation

Ron Bishop · 04-07-2008, 04:32 PM

This is a 4 year old home, This crack is present at the rear of the structure. Any thoughts as to what might be the cause of this crack? I am not sure if it is a reportable condition.

thanks, Ron

Similar Threads:

James Duffin · 04-07-2008, 04:58 PM

Is this a slab house?

Ron Bishop · 04-07-2008, 05:00 PM

yes this is a slab foundation

**Jim Luttrall** · 04-07-2008, 05:17 PM

I can't tell much from the one photo but the first though that comes to mind is re-bar that is too close to exterior surface and is corroding and expanding.

Ron Bibler · 04-08-2008, 04:43 AM

That looks like water expansion under the slab. if it is a one peace slab and footing? then you have some Soil Hydraulic Conditions from water under the slab.

Look for some cracks on the interior floors. You may want to pull back any flooring or carpeting and check the slab. I did not see any rust from the cracks. but dont rule out rebar problems.

Best

Ron
Excellence Exterminating and Thermal Imaging

**Jerry McCarthy** · 04-08-2008, 08:49 AM

My shot:
We used to go to and by Mt. Shasta at least twice a year (trout fishing in the McCloud River) and there was always plenty of earthquake activity in those northern parts of California. Horizontal cracking in concrete foundations in such seismically active areas usually indicated horizontal movement whereas vertical cracking was usually the result of up-down movement from expansive soils, over-loading, and fill settlement to name a few.

**Markus Keller** · 04-08-2008, 04:37 PM

I see two cracks. The other one being above the first, it looks like it was patched at some point. Looks like a recurring problem to me.
Is that a sidewalk or driveway next to the slab?
Other than that I don't know squat about california soil conditions. Good luck.

Ron Bishop · 04-08-2008, 05:28 PM

It's a back porch next to the slab, and 1 coat stucco above it.

Ron Bishop · 04-09-2008, 05:48 AM

Would this be a reportable condition?

Ron Bibler · 04-09-2008, 09:28 AM

You bet. If only a note: in your report.

Best

Ron

Ron Bishop · 04-09-2008, 03:34 PM

I took a pic of it and put it in the report, with a recommendation to monitor.

James Duffin · 04-11-2008, 07:20 PM

This would be a SE/repair item on my report.

Zane Remenda · 11-15-2011, 07:12 PM

Hi Ron,

Typically a horizontal crack is caused by vibrations, such as the post by Jerry McCarthy is logical. Another probable explanation is that it is from large trucks that drive by carrying building materials. Especially if the cement has not "cured" enough.

I have seen this on a few occasions. This was the explanation given to me by a structural engineer.

Zane