QUICK ANSWER PLS concrete over type UF direct bury cable


Old 04-05-11, 02:38 PM
Thread Starter
Join Date: Jun 2010
Location: USA
Posts: 5
Received 0 Votes on 0 Posts
QUICK ANSWER PLS concrete over type UF direct bury cable

I'm putting 2 4x4 posts in the ground, set in quickcrete. I'll need to pour the concrete around, next to, and over two pieces of type UF direct buried electrical wire I buried in the same piece of ground last summer. They are 20-amp 12 gauge and a 30-amp 10 gauge cables, two conductors plus a ground, each. Each one is on its own dedicated breaker in my main panel.

I don't know what damage long term contact between concrete and type UF cable insulation would do. Am I risking damaging the circuits sometime in the future? I don't want to do that.

Can I put the concrete right in contact with the cable insulation? I'm willing to immobilize the cables by doing this. Or do I need to move the cables 6-12" to the side to get them out of the way of where the posts need to be (I can, but it'd be a LOT of extra work). Or should I put something in between them and the concrete? If I need to put something in between the concrete and the cables, what should I use? scrap plywood? good ol' duct tape around the cables? saran wrap or tin foil? just kidding...

Sponsored Links
Old 04-05-11, 05:22 PM
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 21,240
Received 266 Votes on 241 Posts
I never like to entomb wiring in concrete. I would relocate the wire or run it through conduit through the concrete. I like using PVC piping for conduit mainly because I always seem to have niblets of it lying around.
Old 04-05-11, 05:47 PM
Join Date: Aug 2009
Location: USA
Posts: 4,947
Received 0 Votes on 0 Posts
Those posts aren't going to last forever in the ground. At some point that concrete will porabably need to be ripped out to replace them. Something to think about.
Old 04-06-11, 06:47 AM
Join Date: Dec 2005
Location: USA
Posts: 3,188
Received 0 Votes on 0 Posts
It might be a good idea to ask over on the electrical forum. An electrician can probably give you the correct guidance.
I would probably try to protect the cable with PVC. Do you have access to slip a slotted length of PVC over the cable?

As for the posts, if you use the right kind of wood they'll last pretty close to forever. If you are using PT wood don't use the off the shelf stuff from one of the home improvement stores. That wood is minimally treated and drooplug is right when he says it won't last long. Look for posts intended for ground contact and try to select posts that are mainly heartwood.

I have PT ties from HD that i used around a flower bed. After 10-12 years they are rotted. I have PT posts imbedded in concrete supporting my deck that are nearly 30 years old with no sign of rot. the difference is in the level of treatment.
Old 04-11-11, 07:11 AM
Join Date: Jan 2011
Location: USA
Posts: 4,491
Received 31 Votes on 27 Posts
2 X 4's are not below ground rated, use a 4 X 4 instead.
That wire was suppost to be a min. of 18" below ground if was then you could pore the concrete over it.
If the wires not 18" below ground then your going to have to pull it and dig deeper or incase it in gray PVC.
Old 04-11-11, 09:11 AM
ray2047's Avatar
Join Date: Mar 2006
Location: USA
Posts: 33,597
Received 13 Votes on 11 Posts
What do the wires go to? Is the 30 amp 240 volts?

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Display Modes
Ask a Question
Question Title: