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Foundation efflorescence - question

C

Capo

Registered User
Joined
Jul 28, 2020
Messages
19
Location
USA
Hi All,

Trying to get some points of view on a family member's home. There appears to be what is efflorescence on one side of the foundation slab. For context, the home is nearly 20 years old, clay soil, and on a concrete slab.

One side has always had the white marks on the side of the foundation wall. I walked around the neighborhood and pretty much every single home has the same thing. Is this "normal" in this case or does it imply that every home in the community has a moisture or other problem? =) I went back to old pictures from nearly a decade ago and saw them on this home and neighbors homes as well.

The exterior slab looks to be in pretty good condition all the way around but on the side with the efflorescence there are some hairline vertical cracks every few feet in one section and a small horizontal crack that runs maybe 10 feet or so, right above the dirt line.

Does this sound normal for a home of this age and just cosmetic in nature, or could something else be going on here? Should these small cracks be parged and/or filled in some way or best to just leave it alone?

Thanks!
 
I've included some pictures for reference as well.

One follow up question- as you can see in one pic, there is a section where some of the exterior concrete has fallen off. There appears to be a white screw of some sort in the concrete. What is this for?

OneDrive

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Appreciate your thoughts on if this all just looks like normal shrinkage and settling or if more could be going on here.
 
Is number 3 the screw??

Maybe a couple of still shots.

Does the house have an in ground lawn irrigation system??

Lawn sprinkler system
 
Thanks for your response. Yes, the 3rd one is the white screw.

And no, there is not an irrigation or sprinkler system.
 
Also, are the pics not showing up as still images? I see the option to view the video preview (a setting from my phone camera) but they appear as still images by default for me.
 
They show as stills, do you have a high water table? Is this slab on grade, close to any water sources? Any smell of mold inside? Drywall or plaster interior walls?
 
To your questions, ADAguy:

1) Water table - I don't believe so? I checked online at NWIS but not 100% on what metric I should be looking for.
2) I believe it is slab on grade, but not 100%. It's in the S.E., and I believe those are pretty common here?
3) No smell of mold
4) Interior walls, windows, doors, etc. are all fine and level and operate normally.
​
 
MtnArch said:
The way the cracks are located (and proportioned) it looks like it is a CMU (block) foundation that has been parged with plaster or concrete to me.
Click to expand...

Funny you should say that, I was starting to have the same thought. They didn't own the home when it was constructed, so we didn't know for sure what type of slab it was. If that's the case, by the way these cracks appear, would that just be the parging cracking vs the actual blocks (considering everything on the inside appears fine level wise?

Would that also answer what they white screw is? Potentially something securing the block down?
 
That is a CMU foundation with some type of scratch coat on the exterior face. Seeing grass all the way up to the foundation, it is most likely salts or carbonates that are calcifying and leaving the white and pink staining.
 
Thank you all - regarding the cracks, is it reasonably safe to say these are just cosmetic to the exterior parging vs actual cracking to the blocks?
 
Capo said:
Thank you all - regarding the cracks, is it reasonably safe to say these are just cosmetic to the exterior parging vs actual cracking to the blocks?
Click to expand...
The cracks are at the joints in the CMU. Most likely due to shrinkage/expansion related to what appears to be repeated wetting and drying cycles. Not really a structural issue immediately, but it is evidence that moisture is causing damage, and if left unchecked, will continue to disintegrate the homes foundation.
 
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