Tips for EMT in dwelling unit

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crossman said:
I think my statement stands that EMT strapping serves two purposes. One for support, the other to help maintain continuity by preventing the EMT system from wiggling arouns and transmitting this movement to fittings, thereby loosening them.
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I agree, that is definitely the deal. When I run raceways that are where they are exposed I usually exceed NEC minimum support requirements by a long shot. The work will only stay looking good years from now if it is well supported from the start.

But I also know it's a rare thing for one or two flexes of EMT to make locknut's loosen up. But hey, I have been know to use the hammer drill on hammer only to tighten lock nuts. :cool:
 
Generally an EGC is not required and not pulled. At least in the communities I work in. The EMT is the grounding means.

It is obviously very important that all connectors and couplings are made tight. The scary thing is when you work on a job where indenter type fittings have been used (1980's jobs that I've seen). I've had the pipe pull right out of the fittings. One time I was trying to pull in a switch leg for a split receptacle in an existing installation which used indenter type fittings and couldn't get the tape through. Upon opening the wall we found the pipe had pulled out of the coupling probably right after the initial installation. The outlets probably had no ground the whole time.
 
Chicago Code does not require a egc in e.m.t.. We do however follow the support rules. 3' from any box and no farther apart than 7'apart. CEC 18-27-348.13.
 
i did a bank remodel once that was a wood-framed building w/ EMT. they notched all the studs to install; looked just fine, but there is a limit as to how much you can notch out.

as for the code violations in the pics, specifically the recessed lights, i thought you couldn't run conduit to those unless the junction box was listed as a pull box. every recessed light i've installed has a label saying its not suitable as a pull box. am i understanding that correctly?
 
brantmacga said:
but there is a limit as to how much you can notch out.
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Yes, smart $ posted this in another thread.

drillingjoists1.gif
 
This may be an obvious point, but I don't do much conduit
and recently had an job with EMT in wood studs, so it was
news to me.

The 1-1/8" bit through the center was small enough to
meet the framing requirements as posted, and large enough
to get the curve of either 1/2 or 3/4 thinwall through
the top and bottom plates without wasting a lot of time.

You asked for tips, this may be mundane and obvious,
but I hope it helps.
 
I noticed that they are using standard depth boxes also, don't know how many wires they were pulling in, but with all of those connectors in some of those boxes, they are pushing box fill to the limit also.
 
lordofpi said:
I know Scott hasn't posted in a while, but my hat is off to some nice work. As is mentioned in the thread by some of the responders, there is definitely a lack of securing and support for the raceway -- at least at the time the photos were taken.

While making offsets is not a problem per se, offsetting to studs will add to installation time and I probably will run out of room in a lot of locations, e.g. large switch boxes. Also, I suppose that -- as some one else said -- I will be using a lot of couplings. Normally a lack of such is a mark of pride since it means that everything was laid out perfectly, but in this case I think it will just add to the work I have by me trying to figure out out to snake long distances of bent steel tubing into studs.

By the way, I like the concept of spidering out from the ceiling, though I am never crazy about lots of holes in joists (as opposed to studs). Probably (at least for receptacles), I will have one branch for each wall coming from the ceiling, and the rest running horizontally (at 24" AFF) to supply each receptacle.

I was just looking through this:
Caddy Stud Fasteners
and some of these items might really come in handy here.
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This is the one you want to use for speed and adaptability http://www.erico.com/products/CADDYcfcScrwGnBxBrckt.asp they mount the box and or strap the pipe quick and easy to use I sujjest the sms8 screws to fasten the boxes and straps.
 
hillbilly1 said:
I noticed that they are using standard depth boxes also, don't know how many wires they were pulling in, but with all of those connectors in some of those boxes, they are pushing box fill to the limit also.
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I think those pictures are fairly typical of how things are done in the Chicago area - shallow bracket boxes, mud rings turned sideways, no EGC run as some of the posters have said, etc.
 
peter d said:
I think those pictures are fairly typical of how things are done in the Chicago area - shallow bracket boxes, mud rings turned sideways, no EGC run as some of the posters have said, etc.
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We have piped in hundereds of hi rise condos. No egc required in the specs. All of the work was either in the slab or metal studs. Tie wire for all supports with very rare exception. You can get very fast installing EMT. Knowing the length of the 90s by just looking and eventually not needing to measure anything or even marking the pipe for bends.
Pulling branch circuits is very easy, all of the wire is nice and color coded. It might be harder to do a freestanding house with wood studs.
In the Hi Rise Condos, for me anyway, EMT was the way to go.
 
lordofpi said:
Forgive me, but what is the point of turning mud-rings sideways? Is it that much easier to pull?
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It is just how receptacles are placed there, I bet if they put them vertical the customers would ask why.
 
Another trick you can do is (if there are no regulations against it) drill into the building from the outside. This comes in handy at corners so that minimum couplings are burned up, and you might have to drill an extra stud or two, but save on time in the long run.

Additional note, I see someone mentioned counting connectors in regard to wirefill? Connectors not counted when running pipe. Boxes are covered on table 314.16(A).

Good luck with your project.

Old chinese proverb - "A ton of work gets you a pound of luck."
 
I've done a bit of EMT in commercial.
Notching is fairly fast. EMT laid and a 90 down to boxes with a kick, or drill holes and push in from a outside corner.
In Washington State a residential electrician can not wire a house in EMT, but a home owner can. A residential electrician is a restricted to NM with some allowance for RMC and PVC for physical protection.
 
Rockyd said:
Additional note, I see someone mentioned counting connectors in regard to wirefill? Connectors not counted when running pipe. Boxes are covered on table 314.16(A).
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Most likely the reference was to the number of wires. Each pipe/connector entering the box will have at least 2 wires.
 
And 75% fill on a box is the exact number of wires you can put in a box with the the rubber end of a hammer without damaging the conductors? Seen one or two FULL ones.
 
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