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I'm having an electrician wire a lamppost in the backyard. His initial proposal was to do something like this picture shows:

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(The diagram is from this article.) The conduit's rise from the ground and entry to the house would be in a prominent place and would be an eyesore, not to mention difficult to install a paver patio around.

I suggested that since the house is on a crawlspace, the conduit could go straight through a hole in the foundation and into the crawlspace. The hole would of course be sealed somehow to keep moisture and critters out of the crawlspace.

It seems that drilling a hole through the foundation is not to be undertaken lightly. So other than the extra work it requires, are there other disadvantages to taking the conduit straight into the crawlspace below-grade?

Note that the house is clad in brick so a hole through masonry will be required either way.

ArgentoSapiens
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1 Answers1

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My house has the main electrical come in below grade (built in 1967 before they knew better). I would get some small leakage coming in around the conduit where it came through the concrete and later hydro-static pressure pushing water right up into the main breaker box which, though inside, was also below grade.

With a un-floored crawl space, some water leakage is probably not a problem but I'd recommend not taking the risk. You can paint the conduit to match the house and it'll be basically unnoticeable. Or plant a bush in front of it. Or run the wire to the side somewhat and come out of the ground someplace less noticeable.

It's also much easier to run the conduit into the house if you can go through wood framing rather than a concrete foundation.

Brian White
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  • Thanks for sharing your experience. Since conduit wouldn't go all the way to the panel, there is only the chance for water to dribble into the french drain around the crawlspace perimeter. Is that a problem? And the house is brick at the bottom, so I'm not sure it's much easier to go through the sill than through the foundation. Am I wrong? – ArgentoSapiens Oct 05 '12 at 20:07
  • For dealing with any water that enters, it doesn't sound like there is a problem. You will _probably_ be just fine drilling a hole through the foundation as long as you use conduit and seal it properly. I might even choose that path myself in that situation. However, I can't recommend it. (Note that brick is often outside a wood-framed wall and about 1/2 the thickness of the foundation wall.) – Brian White Oct 05 '12 at 20:17
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    Note that brick facing often is built upon the foundation as opposed to just sitting on the dirt. You may find that below grade that you are looking at a full thickness foundation of just concrete. – Michael Karas Oct 06 '12 at 13:23