We had to pull a section of drywall in our garage due to water damage, and since everything is exposed at the moment I'm wondering if we can do some work for the future. I'd like to add an electrical box with conduit running up to the attic, as we are planning for our next car in a few years to be electric. I wouldn't put any wiring in now, but have an electrician wire up whatever charging equipment we needed when the time came.

My question is, can we add said box and conduit now and close up the drywall? Or when it comes time to have an electrician add the wiring will the inspector need to see the conduit?


This sounds like a great plan!

If the attic is easily accessible, the inspector should be able to access it to inspect the conduit sticking up there if he's not satisfied with what she can see in the box itself.

Make sure you look at the different vehicles currently available and the in-wall plugs they need, then get conduit big enough for the wiring and a box big enough to hold the largest plug & wiring. I don't know enough about the amps needed and the plugs required to make a suggestion, but they are bigger than your standard 110v outlet.

  • Thanks for the additional thoughts. I was planning on a double gang box for that reason, but I haven't researched the maximum allowed capacity for different types of conduit. – Jon Nov 6 '20 at 19:17
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    @Jon A big pipe may be a few bucks more today, but it's a lot cheaper than ripping it out and replacing it in a year because you saved a few bucks today! 2" is probably significant overkill for anything you'd need to run, but it will make the pull easy and your electrician will thank you by charging you for fewer hours worked on the install! – FreeMan Nov 6 '20 at 19:48
  • 2" is total overkill, and you'll never need it. It can also be a bit big if you have 2x4 studs. Electric cars draw about 30 amps, so you need 240v 40 amp circuit. For 40 amps, this chart says you'll need 8 gauge wire cerrowire.com/products/resources/tables-calculators/… and this calculator says 1 inch conduit is plenty for 4, 8 gauge wires. southwire.com/calculator-conduit. If you really want to go crazy, you could go 1 1/2 conduit. You could also consider putting in a sub-panel, but really only useful if you want to weld, or use other high power. – Steve Sether Nov 7 '20 at 5:08

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