Running wire through block wall?

Question

A neighbor had his furnace replaced and added central air.

To run the wire to the exterior disconnect, the contractor drilled a hole through the block wall. He drilled from the outside, so the interior hole blew out and is roughly 4" in diameter, at least on the surface of the block.

On the exterior of the house, he ran the wire through the back of the disconnect box and attached the box over the hole.

Inside the house, he packed concrete around the wire to seal up the roughly 4" "hole". So basically, you've got a piece of yellow 12 gauge Romex coming out of a patch of concrete.

He may have packed concrete around the wire on the exterior also...I can't see behind the box.

Is this OK or should the wire have been fed through a pipe or sleeve?

gfretwell · Accepted Answer

It might be possible to say the Romex was "embedded" in concrete (the patch) which is a violation but it is legal to fish through the cores of the block. If this was just caulked there would be no question it was OK. I would say the guy was a hack, just because he didn't drill from both sides and have 2 clean holes.

DanG · Answer

It is too bad that the fella doesn't use a dry diamond core bit or learn to drill a very small hole first, then drill the proper size hole from each side.  A cemented in sleeve with a bit of caulk would sure look better.  A top notch installation would caulk the top and sides - not the bottom - of the new disconnect.

alarman · Answer

I hate to be cynical, but...what hasn't been said is that the "neighbor" probably selected the lowest bid. You get what you pay for.

Michael Dobony · Answer

Poor quality at best. He probably used a hammerdrill and pounded out the inside, making the 4" hole. Yes, it is best to run a conduit from the disconnect box and use sealant, not concrete, to seal the hole around the conduit.

Running wire through block wall?

Join the Discussion

Didn't find your answer?