i have had this idea for years, yet never applied it b-4.....
what would you guys think if an electrician wanted to run a raceway into the kitchen of a house properly sized of course for awg and considered derating if neccessary for # of current carrying conductors... this raceway would terminate in a j box(again prop size)behind the stove or fridge. could there be any argument to 314.29? since they took out that horrible word "readily" doesnt this seem permissible since you wont need to remove any building to get to j box, just the stove or fridge?
trying to save money and time and i think with the price of wire it may actually be cost effective now! or maybe i just like my idea from way back when.

thoughts, comments, ridicules wanted....

thanks,
h20

If I am getting this right, you want to run a good enough size conduit from the panel to a big j-box behind the fridge and then splice/branch out home runs from there. I have seen this method before used for rewiring. It meets code ok. It does not always pass inspection however.

I can't think of any NEC problems. But from a practical standpoint, I've found it is usually more cost effective to install multiple runs of 2 or 3 conductor NM cable. I've been down this road and if you're going to be needing a box larger than 4 & 11/16 square, you're going to be paying a premium price for the box.

I am generally opposed to large J-boxes, they can be a pain when troubleshooting (unless the installer has gone beyond the call of duty and carefully marked all conductors) and if there is an arcing fault in the box, you could knockout quite a few circuits.

However, you should try it at least once, you might like it.

Tom

thanks guys....

i might just try it once and twice if i like it.

h20

Guys- I think it makes sense if you are going to be possibly adding a circuit after the fact but the problem is that your derating would probably catch up with you real fast.

We are seeing more of those Sub Zero type friges that look like they are built in with the cabinets. I try to avoid putting any splices in boxes behind big appliances.

We do pipe a box in the cabinet under the sink that works out well.

Tom

Lupe the maid pulls that fridge out to dust behind it. It is "accessible"

Many kitchen items the area behind would not be acessable. Many things like ovens fridges etc are being installed much like dishwashers. Squeezed in, blind screwed into trims, and on occasion floors and countertops done after cabs can make them impossible to remove without damage. The maid aint pulling them out if I can't!

Why not behind a cabint back?
If you want to trick it out, get a matching scrap of cab matrial and velcro it on as a cover. Or epoxy it to the J-box cover. I have done both before for people who get antsy about wall plates. (With glass fronts) Otherwise I just use a 4-6 gang deep masonary box and a blank wall plate behind Lower cab drawers, where it will be least noticed.

As for conduit derating, you would have beef it up a bit for a kitchen IMO. #10's +... you might as well just run 12/3, or 12/2/2's (4 conductor) in regular runs. Either way, I do it often, and like the sort of central J-box idea for kitchens. Except for the single shot appliances like GD/DW...

Of course, one way to avoid the whole de-rating and wire fill issues is to have the kitchen on a separate, local sub-panel.

Acually, since a kitchen can very easily use eight spaces all by itself, I think a separate panel is the way to go.

renosteinke:

Where are you locating this panel? I like the idea, but not around water or behind anything.

You're quite right in noting that locating the panel can be a challenge. I will usually mount it in a hall, or adjoining room, since most kitchen space is already spoken for. Also, after running my wires, I will have a 3/4 piece of empty EMT going from the panel, into my attic (or crawl space) for future additions.

i had to do exactly what you described on a job where the entire kitchen was an island. We brought three 1" pvc conduits up through the slab in the wall behind the ref.It worked out real well.We used an 8"x8" can with a flush cover.The job was engineered, and the plans showed the can behind the fridge and the inspector had no problem with it.

Do the math on the derating:
Conductors in new NM cables are required to have 90 degree insulation by Article 334.112 and Article 334.80 allows me to use this higher ampacity for derating. Table 310.16 gives me an ampacity of 30 amps. I am allowed 9 conductors in a conduit if I derate to 70 percent by Table 310.15(B)(2)(a). 70 percent of 30 amps is 21 amps. Therefore, I can put 6 hots with 3 neutrals in this conduit, more than enough circuits for any kitchen I've ever wired.
I can pull up to 15 #12 THWN conductors in a 3/4 inch Schedule 40 PVC conduit per Table C.10.

Do the math on the box:
If I run three 12-3 NM out of this J-box, that will give me 19 #12 wires in the box. No devices, no internal clamps, all grounds count for one #12. Table 314.16(A) allows 18 #12s in a 4-11/16 x 2-1/8 deep box. I can get the additional 2.25 cu. inches required by using a single gang tile ring 1/2 inch deep (.5 x 2 x 3 = 3).

Put the box where it is hidden, but accessible, or even be more clever:
What if I only ran only 4 hots and two neutrals? (Double the minimum requirement for a kitchen)

Three fewer conductors leaves me room to install a receptacle in this box and use 1/2 inch PVC, which is good for 8 #12 THWNs. Put this one large box centrally located in the kitchen to minimize the length of the #12 NM cables.