# basement floor cracks, problem?



## joecaption (Nov 30, 2011)

Hard to tell from that close up.
It's normal for some settling cracks to form. That one in the picture is I'd figure on seeing a crack.


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## kree (Nov 11, 2011)

Would another picture help? Was it blurry, not close enough....it's easy enough to go take another picture just let me know what is helpful.

I have about 6 columns in the basement, all with 4 cracks extending out from each other to each other.

Thanks


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## joecaption (Nov 30, 2011)

That would be normal and not need filling.


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## Canarywood1 (May 5, 2012)

Do you know when those column's were put in??


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## kree (Nov 11, 2011)

The home was new construction, 6 years old now.
The concrete guy was awful and made some other goofs on the foundation.


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## stadry (Jun 20, 2009)

they're called re-entry cracks & typically found when no isolation jnt surrounds the column foundation,,, expect your supporting foundation(s) is at the same elevation as the top of footing,,,the floor ( floating slab ) was then install'd,,, in fairness to the conc sub, that may've been as order'd by the bldr,,, if you find finishing issues w/floor's surface, THEN blame the conc sub :yes: many conc subs don't excavate footers but just form, set rebar, place, & finish the conc :yes:

don't see any indication of movement which'd manifest itself by spalls on the crk edges therefore no movement has occurred,,, you'd expect no movement in a bsmt due to temp differentials as the humidity/temp are fairly constant.

IF it were ours ( & we have 'em, too ), smear some acrylic caulk over 'em to keep out rising dampness then finish your floor :thumbsup:

IF a proper jnt pattern had been included along w/isolation jnts, there probably wouldn't have been any random cracking however we typically only see that addl expense w/commercial & industrial work


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## Canarywood1 (May 5, 2012)

"many conc subs don't excavate footers but just form, set rebar, place, & finish the conc "


And that's why those cracks are there,footings should have been excavated,really sloppy way of doing the job.


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## jomama45 (Nov 13, 2008)

As straight as those "cracks" are, I'd bet that they actually used "Zip Strips", which are fairly common and completely acceptable from a non-asthetic standpoint. The likely reason you're not getting any moisture on Saran wrap is because it has plastic sheeting/Visqueen under the floor for a vapor barrier, which is required by code in most, if not all, of the Midwest under baesment floors. I see nothing alarming about anything in the pictures, and don't know of anything you could do to improve the non-issues before moving forward with flooring........:thumbsup:


http://www.brockwhite.com/0p14i4357/zip-strip-contraction-joint-former/


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## stadry (Jun 20, 2009)

good point, jo, & a definite possibility,,, impo, crks are due to reason previously post'd,,, how to proceed was original post & an answer's also post'd above,,, its conjecture to say excavation/footings were sloppy/properly built, postfoundations don't exist, or place blame w/o supporting data,,, it is what it is as ' those guys got paid & they're gone ! ' rule now applies,,, also post'd my solution were that floor mine 

40yrs i've been doing this work & still can't look thru floors OR walls :no: just have to depend on my experiences,,, when all's said & done, more is said than done,,, btw, i like jo's theory better'n mine but still conjecture w/o excavation


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## concretemasonry (Oct 10, 2006)

If the columns/post were on footings a good contractor would make tooled joints toward the columns leading to a classic diamond pattern to eliminate random ugly cracks.

If there is no difference the floor height on the adjacent sides of a crack, it is probably a cosmetic problem since a basement slab does not move much.

Dick


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