[Shop-talk] Running electrical circuit though a foundation

[Mark Watson]

A couple of years ago I ran 100Amp service to the garage and like you I say 
"YAY!"

I agree - don't go through the foundation below grade.  To go through the 
foundation you can use an "LB" fitting.  Also, to make "sharp" right turns 
with PVC pipe, particularly when coming through the wall to go straight down 
into the ground (which is what I did) you need to use an "LB" fitting.  It's 
designed with a gasketed cover so you can pull the wire out into the air and 
then shove it out the exit.  I ran big wire for my 100A service and it was 
"fun" to get it to feed throught the pipes.  Finally managed it though.

Here's a link to an image of an LB fitting: 
http://www.fittings.net/CatalogBySubcategory.asp?CatName=PVC%20Fittings&CatID=8&SubCatName=PVC%20Bodies%20%22LB%22&SubCatID=121

This company sells all sorts of fittings besides the LB:
http://www.fittings.net/CatalogByCategory.asp?CatName=PVC%20Fittings&CatID=8


----- Original Message ----- 
From: "PJ McGarvey" <pj_mcgarvey at hotmail.com>
To: "Shop-Talk Mailing List" <shop-talk at autox.team.net>
Sent: Friday, August 17, 2007 3:40 PM
Subject: Re: [Shop-talk] Running electrical circuit though a foundation


>I just finished running wire for a subpanel to my detached garage in
> conduit... (90 Amps in the shop now - yay!!)
>
> 1. My opinion would be not to drill any holes below grade in the 
> foundation,
> asking for leaks.  Maybe *just* above grade would be better.
>
> 2. plastic conduit is easy to work with, cheap, etc.  I would definitely 
> do
> that.  There are situations where you can use outdoor rated wire
> but I would still go with the conduit - safer and you'll only need 1" or 
> so
> diameter conduit, cheap stuff and you'll already have a trench dug out.
>
> 3. plastic conduit needs to be buried 18".  Metal is 12" if I remember.
>
> 4. Schedule 40 and 80 are your choices - 80 is heavier duty for situations
> where physical contact with the conduit might occur
>
>
> The elbows you'll find for making turns with the conduit or large radius
> elbows, which I assume is because it would be hard to pull wire through a
> tight bend
> so they don't bother.  But it makes for unsightly looking connections.   I
> lucked out by coming through a basement window well frame (wood) 
> underneath my
> deck, so you couldn't see it if you tried.  But at the garage it's more
> obvious, but then I also have it going 4 feet up the wall before it comes
> through the wall directly into my subpanel...
>
> Use the correct cement for electrical conduit, not the type you might use 
> with
> plumbing DWV pvc pipe.
>
> I also purchased a trenching shovel for digging the narrow, deep trenches.
> Alot easier than trying to use any other type of shovel for this purpose.
>
> -PJ