Hole Under foundation at 4180 99th


larger view

Hole dug in foundation between basement door and air conditioner. I will add a 20 amp waterproof duplex power outlet to the outside wall, probably 2 feet above the air conditioner power line. A natural gas pipe runs from the driveway to the gas meter, approximately parallel to the back extension of the house, about 18 inches down. A french drain (in gravel) runs somewhat deeper and farther to the right.


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Viewed from back. The spigot to the left runs to another spigot in the middle south side of the yard, but is otherwise disconnected


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Closer view of the hole. The thin black line marks the location of the bottom of the basement slab, determined with a plastic pipe water level. I presume a pipe hole can be drilled through the foundation just below the line, if there is some way to detect and avoid cutting through rebar in the concrete.


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View down into the hole. Mostly dug with a seed drill and the edge of a flat bar, scooped out with a garden trowel.


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view from inside the hole, looking up. Top of the photo faces outside. A large "mushroom" of concrete extends into the middle of the foundation about 9(?) inches. The hole through the foundation will run above this.


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View looking vertically to the top of the hole, under the foundation. Since this photo was taken, the clay dried out and the gravel fell down. The gravel is a mix of pea gravel and inch-sized sharp rocks, and from the volume of gravel that fell, the layer is one to two inches thick below the slab.

I'm still learning to use my borescope, but a video suggests some plastic between the gravel and the slab. Haven't learned how to attach videos to this webpage yet.

4180hole (last edited 2019-08-30 17:23:25 by KeithLofstrom)