Unique challenge - need suggestions

[CRL]

This has nothing to do with modeling, but I think my problem may may have a modeling related solution. My home suffered a very close lightning strike that apparently came into the house through the rebar in the slab. In addition to taking out several GFCI’s, a bunch of LED lights and some pricy HVAC controls, it blew a section of my concrete slab floor out about the size of my hand. Our floor is acid etched concrete and we need to repair the hole and try to match the color as close as possible. The patch will be partly covered by furniture, but it still needs to be close. Insurance will pay for it, but the only “perfect” solution is to redo the entire downstairs floor. We’d have to move everything out, board the cats, stay somewhere else for a week, etc, etc. Wife ain’t interested in that option.

Here’s a photo of the hole. One thought I had was to use sanded grout in a close match color. Is that stuff hard & tough enough? I’m wide open to suggestions.

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[ednadolski]

Perhaps some kind of concrete epoxy?   I'd think grout perhaps would chip away over time, esp in the thin areas and/or with normal floor traffic.

I don't think an exact color match is possible, tho you could probably get it reasonably unobtrusive.  Possibly a countertop repair person could have some ideas.  It seems to me that re-doing the entire floor just for this would be a big-time overkill  (tho I suppose you could put down some LVP or such).

Hopefully your house has a lightning/grounding system installed?  Good thing no one was using any electrical appliances when the strike occurred.

HTH,
Ed

[Mike C]

  If you could get a color chip off of the floor you should be able to get a paint match . Get it in gloss and it shouldn't stick out too much .     Mike

[nickelplate759]

First thought - I see a floor outlet (clearly so did the lightning) - put a coffee-table train layout there!

Slightly less flippant thought - Did your insurance company put you in contact with a damage restoration company?  I've never dealt with damaged concrete, but at least some furniture restoration businesses employee craftsman that can do an amazing job of matching colors, etc.

[CRL]

Thanks. Those are some good suggestions. Maybe some epoxy product leveled, then painted & sealed to match the surrounding floor area. Ironically, the lightning appears to have entered the house through the slab rebar… you can see the ends of a rebar wire tie at the bottom of the hole. As far as color chips…. Got a baggie with the concrete shrapnel blasted from the hole.

*****! If it ain’t one thing, it’s another.

[Lemosteam]

First turn off the power to that receptacle and remove the cover to see if the concrete carried all the way to the box or not. If you try to do this yourself, you will need to open up that hole a lot more, and back taper the sides, else the patch will just flake off the base material. You could fill it with self leveling hydraulic cement, but the surface texture will not be the same as the original floor.

If you want to add some more attachment structure, you could drill an add some Tapcon screws into the holes with the head raised for the fill material to flow around.

If you use concrete, be sure to dampen the sides of the hole you make so the new concrete will stick and stoke the mix to let it flow and pack into the hole. A drywall trowel should be enough to smooth the surface after filling.

I agree with a good size paint chip to color match.

[CRL]

Another good suggestion about back tapering to key the infill to the floor. But since the insurance company is paying, I’ll be getting a professional involved to actually make the repair.

[Dwight in Toronto]

Maybe search for professionals who repair/refinish marble surfaces/tables/countertops.  These types of services are around, since marble is often chipped, scratched, corroded/stained (eg - red wine spills).  They are really good with epoxy filling, colour & texture matching etc.  Good luck!

[CRL]

Thanks to everyone that responded with some very good ideas. The insurance adjuster wasn’t much help on suggestions.

[nkalanaga]

The adjuster has probably never seen this before!  Coming in through the floor rebar is a new one for me as well.  I've heard of it coming in through pipes, and underground wiring.

[CRL]

The adjuster has probably never seen this before!  Coming in through the floor rebar is a new one for me as well.  I've heard of it coming in through pipes, and underground wiring.

I think my electrical system is grounded to the deep heavy rebar in the slab footings. It’s almost impossible here in the Texas hill country to drive a conventional ground rod deep enough without hitting a big rock that stops you cold. That could explain how the voltage ended up in the slab.

[nkalanaga]

That would make more sense.  Driving ground rods here in Appalachia is also a problem, although I hadn't heard of using the slab rebar as a substitute.  Maybe local codes don't allow it.

We got lucky when we had our new manufactured home installed.  The power company said we had to provide a "6-inch round treated post 8 feet tall" for the electrical connection.  I asked if that was exactly what they wanted, or a minimum, and they said "a minimum".

We'd had a brand-new creosoted utility pole on the hill behind the place, just laying there, still in perfect condition, since we moved in, 17 years before.  When we had the septic tank installed, before the home was moved in, I had the excavator dig a hole for that pole - 8 feet deep.  It was against a bank, and he dug a trench, with a vertical back wall.  Then, after Mom and I had rolled the pole down with cant hooks, he and I tied a rope around the top, with one long end for me to old, standing up the hill.  He picked the pole up with his backhoe, set it in the hole, against the back wall, and, while I held it there with the rope, refilled the hole.

It was very easy to drive  the ground rod, next to the pole, all the way down.  And, with over 20 feet of pole above ground, there's plenty of room for the electric service, telephone, TV cable, and anything else that might come along.

Waste not, want not!