Return to the Electrical Wiring Forum | Post a Follow-Up

 o
Running Electric along Concrete Floor for center floor outlets

Posted by tyjy (My Page) on
Sat, Apr 28, 12 at 17:53

Our room has a concrete floor (no crawlspace or basement underneath for access). I would like to run some electric from an existing wall receptical to the middle of the room. I'd like 1-2 floor sockets spaced a little apart (either side of the couch if possible and not to labor intensive).

How would the experts do it? Use a diamond blade and cut then chisel out a channel for some conduit to run and then imbed the outlets? Would you run it a little deeper and then caulk or mortar over it so to conceal altogether? Is conduit even necessary? We will be carpeting over the entire floor once this electric gets done. My husband can do anything (& he probably already has an idea) but I am hoping for any advice, tips or suggestions so I can "help"! THANKS!! : )


Follow-Up Postings:

 o
RE: Running Electric along Concrete Floor for center floor outlet

Concrete saw to create a deep enough trench for conduit plus at least 2" on top for patchwork to adhere. Run the strands through the conduit, and then use a bonding agent on the existing concrete and fiber reinforced concrete for the patch. Maybe even a bit of drilling into the side for some thin rebar. You don't want the patch to come out, and small chunks tend to not adhere well and come loose. That's a bigger problem for a hard surface floor, but it's not fun to deal with under carpet either.


 o
RE: Running Electric along Concrete Floor for center floor outlet

You can cut into the slab pretty easily as long as it is not post tensioned or has anything else already in the concrete.

for the most part the slabs much stronger than they need to be, so going 2 inches deep is complete overkill, and will actually weaken the slab more then cutting the minimum to conceal the conduit.

You do have to watch they type of conduit, there are different requirements for concrete burial since it is so corrosive.


 o
RE: Running Electric along Concrete Floor for center floor outlet

Wow, thanks so much for the input! Many of the things you guys bring up we didn't consider so appreciate the help. We do NOT want issues in the future that's for sure!
Thank you very much!


 o
RE: Running Electric along Concrete Floor for center floor outlet

We're back on this project & hoping for any final hints, tips or suggestions you can offer?

Is there a recommendation for what type of conduit we should use that's compatible in concrete?

What brand of outlet is recommended?

Would you recommend one 4-plug outlet box or two 2-plug outlet boxes spaced out some? (or is that just personal preference?)

Should we raise the box to consider the depth of the carpet padding & carpet?

Anything else?

Thanks! I'd appreciate any advice!


 o
RE: Running Electric along Concrete Floor for center floor outlet

What else is on the circuit you're extending? Is what you're doing code compliant (likely not)? Are you getting a permit (likely not)?

It doesn't sound like there's enough knowledge or experience addressing this job. Running wiring as you describe isn't like running a garden house through your yard, there are things to screw up and problems that can result.

Unless you want to worry about your house burning down some night while you're sleeping, I suggest hiring an electrician.


 o
RE: Running Electric along Concrete Floor for center floor outlet

My concern would be creating a line for the concrete to crack across.

I don't suppose a thin false floor would be possible? Computer labs and tv stations etc often have a raised floor to allow current and future cabling underneath. Provided it's done right it could be as little as three inches high or so.


 o
RE: Running Electric along Concrete Floor for center floor outlet

alan s: I don't think we could raise the floor but it's an idea I never heard of, thanks!

snidely: What would we screw up and what problems would result? We're hooking into a wall outlet nearby that only has a few other wall outlets on that circuit, and we'd run the wires through a conduit pipe that's won't corrode in concrete (PVC?). We know how to handle the color coded wires. Please tell me what your concerns are.


 o
RE: Running Electric along Concrete Floor for center floor outlet

"Is what you're doing code compliant (likely not)? "

No indications of that.

This is DIY forum, and running a simple circuit (even in concrete in conduit) is not all that complicated.


 o
RE: Running Electric along Concrete Floor for center floor outlet

Thanks for the support!


 o
RE: Running Electric along Concrete Floor for center floor outlet

Brickeye,

Hearing plans from someone who's ready to cut a slab to make two new recepticles from wire run a wall box and then fill it up with caulk, doesn't fill me with confidence that the job is within their ability to do safely and properly. How about you?

In my area, there's no exemption from building code requirements for DIY work. Is there in yours? In fact, it's the opposite, when selling a house, one needs to disclose work not done by licensed contractors and without pulling permits. The result can cost more money than was avoided by going DIY, especially for stuff like electrical work.


 o
RE: Running Electric along Concrete Floor for center floor outlet

"Would you run it a little deeper and then caulk or mortar over it so to conceal altogether? "

The OP is asking how the work should be done.

While caulk would not be great idea, it would also not be prohibited by the NEC.

You must have been born knowing how to do anything ad everything.

The rest of us had to learn, just like the OP.


 o
RE: Running Electric along Concrete Floor for center floor outlet

ahem...

Snidely, maybe you're a poor communicator, but your perception of us is presumptuous. We never said we're "ready" for anything and you have no "confidence" in us because you don't KNOW us or our abilities! (And not that I should feel it a pre-requisite to list our credentials, we actually are in the construction trades so we're NOT as dumb as you imply.)

I really appreciate Brickeyee going to bat for us normal forum posters because it's spot on... we're just making the inquiries and thought this forum was particularly for folks like us. We also may have an alternative objective than you assume! Maybe we, or people like us, won't DIY but, try this, maybe we'll supervise the person we HIRE and we'll know a little bit about what they should be doing rather than being in the dark, oblivious to the procedures. Some people get taken for a ride by assuming every contractor is competent!

So, if we decide that this is beyond our means (which currently we don't) we'll be the first to concede. We also kinda agree w/Brickeyee and consider this "just a simple circuit". What do you know, snidely, that we don't? Why is it more complicated in your view?

(And BTW dear snidely: did YOU know that there actually is a product that can run flat across/on top of the existing concrete floor and under carpet without the need for cutting into the floor at all??? Oh yes, we, the ones you don't have confidence in, already KNOW of a few products, but thought we'd get some DIY ideas as an alternative because this product would cost us $600-700+ for a mere 12' run! Would LOVE to know if you even knew about this, not that I expect a guy like you to confess.)

Here's a few manufacturers Internet links for other folks wondering about this undercarpet product:

http://www.mockett.com/furniture-hardware/technology-into-furniture-integration/power-track
http://www.ampnetconnect.com/documents/ENG/114-6008-Application_Specification-RevD.pdf
http://www.tnb.com/contractor/docs/versatrak_wiremgmt.pdf

Once again THANKS for the support & consideration from those who care to help vs. overreact & criticize. We all appreciate tips & procedures from the PRO's or others who have done this, and don't need the dissing!


 o
RE: Running Electric along Concrete Floor for center floor outlet

Before I get chastised for not mentioning this:

I do not advocate anyone monkeying around with electric if they don't have a clue about it because, yes, it could be dangerous. We all should have "common" sense and I hope we all use it, right?!

that's all : )


 o
RE: Running Electric along Concrete Floor for center floor outlet

If it's a bare concrete floor in a basement, then why NOT raise the floor?

Cutting the concrete is a serious step. A big long line like that will promote cracking and pose a risk of water rising. You also don't know what you'll come across. If a drain pipe is shallow, you may cut into it. You may come across rebar near the surface which you'll have to deal with. Is the basement already more or less finished? Have you ever seen how much dust is generated by cutting concrete? You need to add water to cool the blade and control the dust, so you end up with a concrete powder slurry. If the room's already finished, there'd be a lot of protection to do, and a big cleanup.

What's so all-fired important you need outlets for? Lamps? If it's a suspended ceiling, drop downlight-type shades from the right spot above.

If there's some product that allows you to run stuff under carpet or flooring and meets code, that'd be the thing to go for, IMO.

To fit a conduit in (mandatory) and get sufficient cover over (maybe you'd need less with caulking but that'd be very expensive unless there's a special bulk product) you're going to be going in pretty deep, deeper than you'd think. I'd guess >3" which would be roughly half the depth of the slab. Is there any way at all it could be done run along or through the wall to at least shorten the run?


 o
RE: Running Electric along Concrete Floor for center floor outlet

Thank you for the advice alan s. Yeah, it's for reading/task lamps+ as our seating is in the center of the room but no, it's not a basement (in fact we don't even have a basement!) it's for dabsmack in the middle of our greatroom which is quite large and adjoins other rooms so raising the floor isn't practical.

The entire house is uncommon & most of the rooms are slab on grade. (when we converted this building into a home we actually built a knee wall and raised the floor in the center of the house to accomodate new rooms with plumbing/duct work. Where I want this new electric is in the greatroom which is the slab on grade-if this makes sense).

It's not a suspended ceiling above either and they are a bit high but the ceiling fans do have down lights but not real bright.

Thought now is a good opportunity to try for electric before I finally get my new carpet. I read about the type of cord cover that's flat and covers a cord strung over to the center of the room but I'm trying to avoid that look (even though it'd only be about $17). If I have to I have to but I'd bet most people are sad if that's the final solution : /

We're familiar with how to cut concrete & realize if we do it it won't be the funnest but won't be out of our realm. From the construction we've already accomplished I think the slab is really thick so my DH isn't too concerned about cutting a line in, don't think we're using caulk though, probably mortar, quickset or something like that.

I guess I'm realizing, like everything in this house, we're lone rangers & not in the norm, so spose I've received all the tips I could hope for, for which I am grateful. Thanks so much again for everyone's help.


 o
RE: Running Electric along Concrete Floor for center floor outlet

I have seen those things before, because I've tripped over them. They put a mostly invisible ridge into your carpet that can be quite troublesome. Unless you're putting it in an area where people don't walk, you may do better with simply running an extension cord and putting one of those ugly "v" shaped vinyl things over it, on top of the carpet. At least that way it will be visible. One of the products you linked to can't be used over a slab. And the wiring for one of them needs to be run directly back to electrical panel, hope you noticed that.

If you're going in the direction of these products, what's up with the questions about cutting into a slab? Sorry, the additional information makes me more worried for you, not less.

I wish you well and hope you can avoid a problem down the road. I wouldn't hire a electrician to do plumbing, nor a plumber to do roofing, etc. I'm glad you're "in the building trades", but unless it's you're an electrical and/or foundation contractor, you may be making a mistake by doing it yourself. Do what your customers do, hire someone who has the training and knowledge to do the specific task safely and correctly.


 o
RE: Running Electric along Concrete Floor for center floor outlet

snidely: those links were the three suggestions we were given by an electrician friend. I think DH thought the Versatrak would work the best in our case (I didn't really look at any of it real close myself).

We were inquiring about the alternative of running the conduit in concrete just to compare processes/prices cuz the Versatrak idea seemed so expensive. We've never used Versatrak or experienced it so the thing about tripping over it is exactly what I DON'T want. I was assuming the ridge would be hidden in the carpet pad somehow, hmmm, so maybe that's not a good idea after all?

The ugly v-shaped vinyl thingys to cover a cord across the carpet aisle is what I hoped to avoid the most and assumed those would be even more of a trip hazard.

Ugh, doesn't seem like there's a very good answer for us : / but thanks for taking my response to you well and thanks for the advice!


 o
RE: Running Electric along Concrete Floor for center floor outlet

On the first page after the cover, the Versatrak brochure says it is not recommended for installation on any slab on-grade floor. That was your first choice?


 o
Under Carpet Power System

Had to consult w/DH and I may have misunderstood something... glad you responded as I don't want future readers to get the wrong information!

What I found out ... for OUR application ... is apparently the Versatrak type we initially selected is no longer available so we switched to the "Tyco Products-AMP Under Carpet Power System" (for which the above mentioned $600-$700 quote was for; price range based installing one receptical or two recepticals).

Re: concrete slabs and the way it works: there's a tape type product that can be laid over the concrete floor for moisture barrier...then the under carpet power strip (AMP)is laid over that ... then a top shield is laid over the power strip .... and lastly a hold down tape for it all.

snidely: Does this sound appropriate to you? Or, do you know of another product/brand that would work the same that may cost less but be just as applicable? Thanks


 o
RE: Running Electric along Concrete Floor for center floor outlet

Ok, so much for the under carpet power system idea:

After reading the technical specs it appears the system that we were considering is only recommended for removeable CARPET SQUARES and not roll carpet (wall to wall) & the reasons are fair. Unless we find another company, looks like we're back to cutting the concrete slab idea or use an over carpet wiremold product.

: /

If anyone has an idea please write. Thanks


 o
RE: Running Electric along Concrete Floor for center floor outlet

Have you considered building a decorative column that goes from floor to ceiling, on which to mount your receptacle(s), bringing power from the ceiling?


 o
RE: Running Electric along Concrete Floor for center floor outlet

just cut a trench with a concrete saw 6" wide, 4"deep. Lay in 3/4" pvc conduit and a couple carlon floor box(see link). Pour back concrete and finish off with a couple receptacles and brass covers. You will be done in a day.

Here is a link that might be useful: round floor box for 3/4


 o
RE: Running Electric along Concrete Floor for center floor outlet

This is the cover you might want for the floor box.

Here is a link that might be useful: brass floor box receptacle cover


 o
RE: Running Electric along Concrete Floor for center floor outlet

Do plan on containing the VERY abrasive dust as well as all of the water that a concrete saw will need to keep the blade cool. As I mentioned upthread, you also want to use a bonding agent on the old concrete and use a right angle drill to drill a couple of holes in which to epoxy some rebar "keys" so the new concrete (NOT mortar) will adhere to the old and act as a whole. You need to use individual wire strands, not romex and set the outlets just at the finished floor height. That doesn't include the padding or carpet.

Of course, you want to be 100% sure that your slab is NOT a post tensioned one. If it is, forget cutting into it at all.


 o
RE: Running Electric along Concrete Floor for center floor outlet

Thanks SO much you guys for your suggestions.
The specifics is what I needed. Very much appreciate everyone taking the time to help!

hollysprings: would you make the trench 6"w x 4"deep as btharmy suggested? Or is that overkill as brickeyee said even at 2" deep?


 o
RE: Running Electric along Concrete Floor for center floor outlet

The groove in the concrete needs to be deep enough to make a thick enough patch over the conduit (at thr thinnest spot in the patch) to not crack ad look bad.

That is about it.

You need concrete tight connectors for all conduit and conduit to box joints, and a type of conduit rated for direct use in concrete.

It is a nasty dusty hand job for the most part.

Scoring more than just two grooves can go a long way towards preventing going through the slab all the way when breaking out the groove material.
There are advantages two, three, or more grooves.
You can ten use a chisel driven in a groove to break off a section of concrete with the next groove as clearance.

If the spacing between the grooves is smaller it is more likely to break off near the bottom of the grooves.


 o
RE: Running Electric along Concrete Floor for center floor outlet

Thanks gang! You were all so much help & I greatly appreciate all your time. I will let you know how it goes IF it goes!

(I'll keep watching for any added ideas) but if not
Over & Out


 o
RE: Running Electric along Concrete Floor for center floor outlet

Wild idea. A contractor who does directional boring might be able to bore under the slab from the perimeter of the building to a hole in the slab about a foot square at the desired location . A UF cable could then be pulled from the hole to the outside.


 o
RE: Running Electric along Concrete Floor for center floor outlet

"hollysprings: would you make the trench 6"w x 4"deep as btharmy suggested? Or is that overkill as brickeyee said even at 2" deep?"

Depth all depends on the box you choose. You are going to have a hard time making the transition to the box in a 2" or less trench. I'd have a hard time with finding a box to fit in a trench so shallow. If you do, it will barely be deep enough to accept a device. It is just silly to try. 3/4" conduit is actually 1 1/8" outside diameter. The couplings are approx. 1 3/8". That is only 5/8" of concrete cover, sure to crack and break up. Besides the fact of the radius of a 3/4" PVC 90deg elbow. You don't want the radius sticking out of the wall to floor transition.


 o
RE: Running Electric along Concrete Floor for center floor outlet

bus driver: thanks for that suggestion! I do know we had to do a horizontal boring like you described for a water line from the well...but that was for an existing opening in the utility room floor. I'll ask the DH what he thinks of this.

btharmy: you're right I think, it's the size box that'll determine the depth and/or transition to the box plus I DO NOT want the patch to crack & break up!

I just posted on the Flooring forum hoping for anyone who may know of an alternative Under Carpet Power Supply that can be used under rolled wall to wall carpet vs. carpet squares only. CROSSING my FINGERS someone knows of a source cuz that'd save sooooooooooooo much work ~ that we're dreading but may be unavoidable : /


 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!


Return to the Electrical Wiring Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.


Learn more about in-text links on this page here