what is the most home runs you have encounterend in a residential home. i ran 26 last week not including the low volt tv and phone lines. keep in mind i'm still learning!!!!! that was the most for me in a 200 amp service so far. just curious, is there a code for that sevice? i know your limited by the amout of breakers in the panel, but idiots can easily get around that.

There are not codes about the absolute number of circuits in a house, but you can't have more than 42 in any single panel. There is a code about the total load vs. the size of the service, the service conductor size and main breaker size. Seeing as you said you are "green", maybe you should learn some more basic codes from the NEC before doing more house wiring.

Doing a large house now with well over 100 homeruns.

2 x 200A 42 circuit panels
150A sub for AC units
100A sub for general circuits
100A sub for pool equipment
50A sub for communication/automation equipment.

And we are still running out of space...

26 HR Does sound like a lot for 1 residential panel if you are using EMT.


A 3000sf home with the normal extras (2 central A/Cs, jacuzzi, pumps, DW, disp, microwave) we might have 10 or 12 HRs most are 3/4".
Something like this:
Ground
A/Cs
Basement
Kitchen GFIs/appliances
Kitchen lights + other
Foyer + other
Living room + other
Luundry + other
Master BR + Master Bath
2nd Fl BR + Bath
Smoke Detectors (deicated 1/2")

Other might be 1st fl BR, Bath, Garage, Dining Room, Study, mud room, Eating Area, Pantry, Laundry room.

The HR are oversized to make pulling easier and for future. I could use less HR but it dose make it a bit easier when there are just a few networks. I like to write on the pipes where they go to make pulling and identifing circuits easier. It might make it easier on the next guy too.

Tom

I've never done an entire home in EMT. Must look real nice when your done. Alot more planning must go with a job like that. Man, a whole house in EMT. I would imagine the price would be much more than just Romex.

The NM vs EMT cost was studied in an area near me a few years ago. It is an area where the local code requires EMT for single family dwellings. It was found that for the typical 2000 square foot tract house the EMT installation costs a about $500 less than the NM installation. Given the house cost of $140,000 to $160,000, you don't even notice the cost of the EMT.
Don

SJT,

Follow this link and use the arrows at the bottom to go through the photos like a slide show.
http://www.electricalmatters.com/gallery/members/EMT_Ruff_001

thanks for the slide show. very interesting. I've never seen a house done in emt.

You will still have to pry the romex from my cold dead fingers before I do a house in emt though.

Sandro.

I worked for a contractor that did a medium sized home with 60 circuits, but at least 20 of them were unnecessary IMO. (A 15 amp circuit with 4 recessed cans and 2 small sconces on it, 8 circuits in the kitchen for instance.)

Don, you said "a few years ago", so do you think with with the current copper and steel prices that comparison would be invalid? (not that it matters much since EMT is required )

Peter

[This message has been edited by CTwireman (edited 03-22-2004).]

No lie. i've done 20,000 sq. ft. houses with light touch systems with well over 300-400 home runs including the lighting circuits.

I did some work in an ancient multifamily house with a live-in landlord who was an old eccentric electrical engineer. He had somehow convinced passed electricians to wire every single duplex receptacle and appliance on it's own dedicated circuit. The basement ceiling was covered in huge bundles of MC/AC/BX wrapped together with zip-ties. There must've been the better part of a hundred home runs with nothing properly labeled. And because all the cable assemblies couldn't be terminated into one panel, they brought them into big troughs to switch over to conduit and THHN, none of that labeled either.

I ended up walking off that job.

-John

[This message has been edited by BigJohn (edited 03-22-2004).]

I'm with Sandro here. I'd quit the business if I had to wire a house in EMT. Our typical house is 4500-6500 sq ft and has 75 home runs. I can assure you it would cost much more than $500 additional to do it. Our average home is $16000 for romex, in EMT I think another $10k would be needed. But we don't do much with EMT, so I may be way off.

Wow Mean Gene! That looks like a nice job they did with the EMT there. ( I would hate to have to drill all those perfect holes ) I have yet to see that on a job I thought the EMT was more for the commercial aspect of this trade.

I just learned something new today. Thanks.

WOW,....That is truly a work of art,...my hat comes off for that guy,..it would take me a real long time to rough a house in EMT,as I don't do much piping,..just here and there...
Russ

If I'm not mistaken, it's required by code in some places believe it or not. Chicago seems to stick in my mind for some reason.

Are there any members out there where EMT is required for residential/dwelling units? Am I right about Chicago??

Chicago and suburbs homes are all EMT. We don't do anything but conduit. We do a lot of nice bending. It does take a bit more time. There is a difference between making pipe bent enough to connect and making a piece fit so well like art. A number of EC save time by having no offsets, crocked pipes, etc.. A few will even connect and strap one side of a stick then then bend by hand where the other side goes. It turnes out like a ark.

I knew guys that tried doing a home it the stix with NM cable. It took them way longer than piping because they are not skilled it that area.

I read EMT homes are done for about $10 more per opening. When new homes it the cheapest towns start at $250K it does not change the price much but it is a better system.

Tom

I am just finishing up a 5500sq.ft. single story home where I used a combination of NM and 3/4" EMT. I kept close track of costs so I could compare with using all NM. I did it this way because this GC wants most of the wiring in the crawl, not in the attic. It was a nice 5 block crawl and the thought of 4000' of NM and all the stapling in there made me tired all over. The house had a 320A service with (2) 40 circuit ML panels. Out of one panel I ran (7) 3/4" EMT runs to (7) locations spread out in the crawl and terminated in 12"x12"x4" pull boxes. I wired the receptacles and switches in NM through the walls and dropped the home runs into the crawl and terminated in the pull boxes. Each pull box has a EG bar and a laminated card identifying each set of conductors. There isn't more than 10' of NM exposed in the crawl anywhere. Just for kicks I ran all of the crawl lighting in 1/2" EMT. This GC wants a 100W lamp for every 500 sq.ft. of crawl space. Out of the second ML panel I did the same for the workshop and all 240V circuits (A/C, range, dryer)keeping the large loads and motor loads in the separate loadcenter should help avoid flicker-up. This GC is extremely picky. If you do run NM home runs in his crawl he expects you to snap a chalkline and keep all the runs parrallel. He loved the EMT! The network, phones and CATV aren't in EMT but I used bridle rings and it looks sharp. With the cost of 12-2 NM around here @ $155.00 per 1000 and 12 THHN @$56.00 per 1000 plus pulling 1 #10 green in each pipe and using multiwire branch circuits, I came up with a materials savings of just under $750.00. I don't know but I would guess that I saved on labor hours too since I didn't have to spend the time stapling hundreds of feet of NM. I have another home to do for this GC coming up and he wants the same system used on it. I bought several 500' rolls of THHN @ $22.75 before it went through the roof in anticipation of this next house. This was a custom home and it was fun to do. It may be a different story in tract homes where time and money are stretched thin.

I recently did a house in emt at the owners request. Mine didn't look as good as the pictures here,but it wasn't bad.

I can appreciate the versatility of an emt system after doing a house like that.

Homeowner wanted to add some recessed lighting. It was pretty simple,no fishing wires in the panel,just add a couple of ckts by pulling more wires.

Russell

Fred that sounds like a really nice job.

I am a little curious about the number of current carrying conductors in each conduit.

The only reason I ask is with 3/4" conduit you can easily get into derating issues.

Bob

There is one house that I am inspecting right now and the house was under construction for 3 years now and it is still not ready for a final inspection. The house has 600 amp service, 7-9 sub panels, (I can't remeber how many, I haven't been there for a while. Indoor swimming pool, indoor waterfall, which will empty into an indoor fish pond. Stand by generator, 6-9 HVAC units, inculding 3 for the pool area. It has it's own elevator, beauty salon, 6 car garage. Plus a few more items that I can't remember, like a hidden room behind a book case. (I think)

IWIRE, the typical 3/4" EMT has 2 #12 MW branch circuits(4 hots, 2 neuts)2 hots with dedicated neuts(for AFCI circuits) and a #10 EGC. That's 10 #12 and 1 #10. With 7 3/4" conduits, there isn't any excuse for over filling any of them when leaving a 40 circuit panel.

Fred if these circuits are 20 amps you just made it.

In the pipe you describe you have 8 current carrying conductors of 12 AWG.

Apply the 70% adjustment required and you end up with a 21 amp rated conductor.

If you had not used MW circuits you would have had a problem, once you get to 10 current carrying conductors it would be a 50% adjustment resulting in 15 amp rated 12 AWG.

I asked because I see these derating rules forgotten about often.

Bob

iwire, derating was figured in. In the pipes where there isn't an AFCI circuit needed there is another MW circuit instead making 6 current carrying conductors. All circuits are protected @20A.

Derating ... its a pain. Turns out here in California temps can get up to the low teens above a 100 so add an additional 87 percent derating to the 70 percent derating and the arguement for conduit gets tough! It still makes for a much cleaner appearance if you have to pipe out to panels in the case of a service change where the panel site is changed as well. Piping romex for that last 3 feet verses thhn makes for a lot more pipes. In one recent case I was able to reduce the number of conduits from 7 to 4 -- much nicer looking!!

Hello all new here. The most home runs I have ever seen, out of place .

About 5 years I got a service call to go terminate a panel for a gentleman that had wired a very large basement all by himself with no clue.

The man had gone and pulled a home run to each and every recep. in the basemant. It was all I could do to keep from laughing. I told him I had some good news and some bad news. Bad news was he was going to need some re-wiring. Good news he already had plenty of wire.

Neil

I see a lot of conduits in those pictures not secured properly. Do you guys get away with this. We would be bending offsets to get the pipes to the stud so we can strap them, or adding blocking in to strap them..............Brian

We would have the same issue here ZR, depending on the Township.

Just a thought on the pipe securing.

I would think a lot of inspectors might lighten up a little on the support rules in areas that will be covered with Sheetrock.

Exactly what outside force will be pushing and pulling on the concealed raceways?

I know the code does not say supports unless concealed, but I think some inspectors use commonsense.

We used to get away with not fastening. Then the AHJ starting using the NEC by the book. Hey, if I have to strap more in exchange for an inspector that submits to the code just like we do, I'll take it any day. No more "his way because he likes it that way".

But for (what used to be before steel prices $.22 each) just smack a couple of these http://www.erico.com/products/CADDYcfcCS812ScrwOnConSuppt.asp on there and your good to go.