New Designer here, not architect or contractor. I just came on board a project where the client wishes to purchase a display kitchen and install into a slab on grade house. My question is- can you score a small channel into a standard concrete slab to lay an electrical supply to an cooktop on an island? I’m not sure what the final floor material will be yet. It seems like you wouldn’t have to go down that far and could epoxy fill it in. Could this in any way affect the integrity of the slab?
Thanks for your expert advice.
Replies
Depends on how deep the slab is, which can vary from about 3 inches upwards to a foot. In general what you suggest can be done, though it's often just as easy to cut all the way through the slab. Whether slab integrity is an issue depends on a number of factors, a major one being simply how long a cut is needed. Worst case some extra reenforcing rods would have to be installed (eg, epoxied into slots) across the cut.
This is not a particularly complex problem, though -- it's done all the time and there are experts who can deal with whatever specific issues your particular case involves.
Keep in mind that any electrical in the slab must be in a conduit (pipe).
happy?
Thanks for the reply. I didn't think this was too complex but I am meeting with the homeowner at the site tomorrow morning and wanted to have an idea to advise about whether the kitchen would work. I feel more confident in making that call.
I don't believe it is post-tensioned. Older-'60s or '70s home, but in California so the earthquakes create pretty strict building codes here. Thanks again for the info.
In general slabs can be cut without any problems.
But you need to be aware that in some areas of the country post tensioned slabs are used. And those you can't cut a cable. So cutting needs care planing and testing.
And if you do find you can cut the slab, be sure to have the conduit inspected by the relevant jurisdiction's electrical inspector(s) before filling it back in. --Ken
A long while ago I saw an electrician run a flat (and I mean FLAT) wire, must have been 10 " wide , on a concret basement floor to a surface maounted floor receptacle.
This wire was then carpeted over. It took a junction box the size of a 100 amp panelboard to make the connection to a standard piece of romex. This juction box was mounted flush in a wall.
Maybe this sort of thing can be installed under kitchen flooring. Ask an electrician.
You'd also want to check with local inspectors. That sort of thing may not be allowed, even if "legal" per NEC code and UL listing.
If ignorance is bliss why aren't more people
happy?
That flat wire is called flat conductor cable (FCC), and you're right, it looks like romex that's been run over by a million ton steamroller. It's 'bout as flat as a piece of paper. Can be used for up to 20 amp branch circuits.
FCC is intended for use in commercial office environments. It can be used only under carpet squares. It's not allowed to be used in residential occupancies (or schools or hospitals) per the NEC.
As far as the original poster's question--I've had to get power to a few islands, and I have someone come in and cut the concrete slab and break it out. Conduit (either intermediate metal conduit or sched 40 PVC) can be run just below the bottom of the slab--zero burial depth is OK under a building.
Cliff