Inspecting concrete foundation

I did an inspection on an octagonal shape home in Ewa Beach, Hawaii and came across aggregate showing through the slab foundation. This house was a project of a local high school building methods class. The students designed the house and had licensed contractors build it. The aggregate showing through was a good example of honeycombing. This is an indication of poor consolidation. Sorry no Pictures. Has anyone else come across this in their inspections?

Maybe it is a decorative concrete floor with Lava rock used as aggregate giving it a decorative look, You are in Hawaii,

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This was located at the outside of the foundation of the house and noticed at two locations around the perimeter. Not decorative.


Did it look something like this?

It typically is not a problem, but of course that depends on severity.

I like this article


The article is okay, but after nearly 30 years of playin with “mud”, I can tell you that some of the info is semi misleading. I don’t have time to get into all of it but I will note, in the last section about patching “honeycombing” (I have always called it popcorn) the article says to wet the area to be patched before applying nonshrink grout, but it doesn’t say what to wet it with. :thinking: Ok that’s sorta correct. Here’s a little tip, if you are going to do this yourself, DON’T USE STRAIGHT WATER. The grout will not bond correctly to the concrete, especially if it’s fully cured, and in time will flake off. Wet the area with what I refer to as “Goats Milk”. It’s an acrylic bonding agent. Brush the product on, allow it to absorb in some. Once it becomes tacky but is still wet, then apply the grout with a margin trowel and firm pressure. For large areas a pointing tool or wooden dowel works good to push it in to all the crevices. Moisture content of the grout and timing can be the difference between a good patch or one that just falls out. … I will save the finishing tips for another day :smirk:.

So @rmelton2 if there’s no exposed rebar, big cracks, or chunks falling off, patch it and be done with it. If done correctly, the patch will outlast the slab.


Good stuff! I think this will help many inspectors.

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