How to attach subpanel to Concrete

[Todd.Brock]

As part of the kitchen remodel, I am moving aN oven. I have a circuit running through the basement that fed the original range. It is 6 gauge copper wire, and a ground that looks to be about 10ga. It is breakered at 60 amps.

I intend to repurpose this circuit for a subpanel. It will power the new kitchen oven that only requires 30 amps. I will use the remaining capacity for a small woodshop in the bsmt

What is the best way to do attach a panel to a concrete foundation wall? Tapcons? Piece of plywood held on by tapcons, then screw board to it? Sleeve anchors?

My original intent was going to cut 2x4s the size of the panel, attach with tapcons and then screw panel to 2x4. But that was just my plan and is subject to correction!

 

[G_P]

I would put up a piece of plywood and then attach the panel to that.

 

[TommyK]

Tapcons? Piece of plywood held on by tapcons, then screw board to it?

^^^This^^^

 

[ishiboo]

Avoid attaching it directly to the concrete or using pressure treated wood. If the wall is dry and nothing will need to be mounted/stapled near the panel, I would use threaded inserts in the concrete with washers to space the panel out from the wall.

Otherwise, plywood works wonders. Don't use OSB, and don't use treated.

 

[Todd.Brock]

Thanks for the info. I think I have some 5/8 plywood. I should double up so there is enough to bite

 

[teamextreme]

I would use lag bolts and lag shields directly into the concrete. What is the advantage to using the plywood?

 

[Stuart in MN]

A basement wall is typically considered a damp area (or at least, an area that may become damp.) As a result, an electrical panel needs to be spaced away from the wall. It's normally done by bolting a piece of plywood to the wall with spacers behind it, and then bolting the panel to the plywood.

Having the panel on a piece of plywood can be handy, as it provides a good place to fasten down wires or to install other things such as telephone panels, cable TV connections, etc.

 

[Wirepuller]

on new and significant resi work I use tap cons to fasten 2x4s to the foundation wall I then mount plywood to that. It spaces the panel board off the concrete wall and gives me room for wood screw to bite. The plywood also lets me mount the panel gfi and any future pieces of equipment. looks more thought out and professional, its quick to do and doesn't cost much.

 

[teamextreme]

A basement wall is typically considered a damp area (or at least, an area that may become damp.) As a result, an electrical panel needs to be spaced away from the wall.

Sounds reasonable, but can you cite a code reference for this? I've never heard of this requirement in NEC.

 

[Charles (in GA)]

Is the old stove wire you are repurposing, a four wire (two hots, a neutral, and a ground) or a three wire (two hots and a ground)?? If it is three wire, you won't be able to reuse it, as you cannot make any 120v circuits with a three wire.

 

[Todd.Brock]

Charles, I was very surprised that it was. 3 six gauge conductors -red,white,black and one bare ground which looks to be 10 ga. The conductors are stranded, all wrapped in black sheathing. I forgot to look and see what "type" wire it's listed as. I know that affects the allowable amps b/c it has to be derated if nm-b or uf-b

 

[Stuart in MN]

Sounds reasonable, but can you cite a code reference for this? I've never heard of this requirement in NEC.

Articles 408.37 and 312.2 in the 2014 edition. The question is what do you consider a damp area; I'm not sure if a concrete wall in a basement is always considered a damp area, but it's likely to be one because of condensation so as a matter of course a panelboard on a basement wall is normally installed with spacers or on a piece of plywood. As mentioned above, there are other advantages to using plywood anyway.

 

[Todd.Brock]

Thanks guys... I love this place!

 

[zmaxmotorsports]

Articles 408.37 and 312.2 in the 2014 edition. The question is what do you consider a damp area; I'm not sure if a concrete wall in a basement is always considered a damp area, but it's likely to be one because of condensation so as a matter of course a panelboard on a basement wall is normally installed with spacers or on a piece of plywood. As mentioned above, there are other advantages to using plywood anyway.

Panels get mounted directly to concrete/block walls all the time.

 

[JohnX14]

I would mount 2, 2x4's to the concrete with a ramset or tapcons then mount a piece of plywood to the 2x's and mount the panel to that. I've done about 3000 that way.

 

[Beemer533]

Whether it is code or not, if I am putting a panel up on bare concrete walls I like to use a good size piece of plywood to give me space to easily and neatly secure the romex coming out of the panel.

When I redid the main panel in my house last year, I used 3 vertical 2x4 flat on the concrete (older house with fairly uneven walls)I shimmed them all to be flat to each other and used hilti anchors to secure them to the concrete. Then I just screwed the 3/4" plywood onto them. It came out very well so I did the same thing for my new pex manifold and all my network/alarm gear.

Here is the panel I used for my pex install; I don't have a picture of the panel on my phone, but I did the same install there..

This post has been edited by the NSA

 

[alfredeneuman]

The embossed "dimples" around the mounting holes of most panels space the panels out enough to get some airspace back behind them. It's all the Code requires.

Washers aren't needed ...... and they are a pain in the neck to install behind the panel.

 

[toplessHO]

The embossed "dimples" around the mounting holes of most panels space the panels out enough to get some airspace back behind them. It's all the Code requires.

Washers aren't needed ...... and they are a pain in the neck to install behind the panel.

agree if it has dimples on the back that are part of the mounting holes then youre good to go. But the plywood makes a nice job too.