Not All Drywall Contractors Are The Same.

I am doing the finish on a office remodel now and wanted to share a couple of pictures of the work the drywall contractor has done.

For a change it is great, and this from guys that are paid by the board not by the hour.

[Linked Image]

I have about 400 devices in this job and 99% of the drywall cut outs look like these ones.

If only it was always like this. [Linked Image]

By the way, this is what it looked like before drywall.

[Linked Image]

Bob

Bob,
I don't do any cable type installations, so I have to ask about the "drip loop" in the right side stud space in the bottom picture.
Don

"Drip Loop" [Linked Image]

The roof is not tight. [Linked Image]

If things go the way we would like, it goes like this.

We arrive on the job before any interior walls go up.

1)Mark on floor with spray paint all electrical circuits and locations, we have a color code that identifies what it is, power, lights, HVAC, FA etc.

2)Install every bit of cable attaching it as high as possible to trusses beams and decks, leaving a coil more than long enough to reach the boxes yet to be installed.

3)Walls get built, we install all boxes.

4)Now all our guys have to do is look up and drop the previously run MC down the wall and cut into the box. The slack is already "waste" no sense of putting it in the dumpster, we use what we need in the box and work the slack back into the ceiling leaving tie wrapped coils of slack almost every where.

These come in very handy when things need to get added, as in slack to cut in a J-box.

However the wall you are looking at has a large air duct right above it, no place to leave slack, resulting in the drip loop, if we need slack it will pull up through the cable supports.

Bob

I also noticed how clean the jobsite is!!
What is the one conduit run for?
Far wall box supports - very nice - how many times do we not see these installed.

Pierre

The GC kept a very clean site and we would help to do that too. [Linked Image]

Along with the obvious safety factor of a clean job site, I believe it helps the attitude (clean, professional, etc) of the workers (myself included) speeding the job along.

The pipe run is for the cabling contractor, it was part of our contract to provide 3/4" raceway up to the ceiling.

We used about 1500 cable supports and every box is a 4" sq deep with a box support.

How many of you do like we do and use 3/4" raised rings for 5/8" Sheetrock.

It makes the ring flush with the drywall and gives great support to the devices. [Linked Image]

By the way, if the walls where not going to be sound insulated with fiberglass batts we would have anti rattle clips on the MCs where they pass through the studs. [Linked Image]

A very neat job!
We also use 3/4" rings on 5/8" drywall.
That extra 1/8" is actually "absorbed" by the head of the 8-32 screw tthat attaches the ring to the box.
Seems kind of costly to use deep boxes throughout, though.
What brand/type of box is that, Bob?
I see the internal cable clamps...S

Bob
How many electricians would be on a job like this/how long are you usually roughing a job like this? Do you ever ask for partial roughs from the inspector?

Pierre

Good Morning Scott, Thank you.

I am just a small part of a large company, the supplies are the "deal of the moment" provided by purchasing.

I ask for stock from purchasing and they shop it out.

As for the expense of deep boxes it is a non issue for us (that may change if steel keeps rising) in our market it is all about speed, the faster the better.

We have standard procedures for doing things and deep boxes are one of those, we always feed the switch so minimum 3 12/2s per switch box add to that a typical wall mount motion sensor and maybe dual switching.

By always using deep boxes the guys do not have to stop and think about box fill, you need to add a cable, go ahead and do so.

I am not saying our way is the only way, just that it works for us, employees can be rotated through different jobs and it is all the same for them.

In some ways this stinks as some guys become no more than assembly line workers, but some are happy not to have to think.

The ones that want to think get better assignments, control work, Fire Alarm running a small crew etc. [Linked Image]

Bob

Pierre This area is on two floors covering about 30,000 sq ft.

I had rough wall inspection on each floor and a rough ceiling inspection on each floor.

The inspector has been out 4 times so far and will be out 2 more times for finish.

This job had 12 guys for 2 weeks to pull (about 40,000 ft MC) and box the majority of the work. During this time all the lighting feeds for the 2 x 4 troffer are also hung from the ceiling and the independent support wires for the fixtures (required in MA) are installed.

The MCs for the lights are stripped, connectors and wires nuts installed.

Bar boxes for exit signs, smoke detectors, occupancy sensors etc are also all hung from the ceiling.

All of this is done long before the grid goes in, if the job drags we will wire and hang the troffer from the support wires before the grid is installed. This is not how to make friends with the ceiling contractor though.

Once all that was done we have cut down to 5 guys to do finish work and work on cleaning up existing conditions.

Bob

Nice, Neat Job Bob!

(hey that rhymes ... [Linked Image]

)

Refreshing to see. I'd like to see more pictures of stuff done right.
[Linked Image]

Bill

Bill,
I couldn't agree more. Lots of Good jobs would be great to see here. I unfortunately don't get to see many jobs before something breaks, or a warranty issue comes up(I'll look for some)

Bob,
The "no thinking" reasoning for the deep boxes has real merit. I'll bet most of the problems we run into were caused by "non thinking" people's thinking.

[This message has been edited by electure (edited 03-28-2004).]

did you use anti-shorts if so you did a good job

Big guy: Anti-short's are not required for MC cable. Only AC cable requires the use of them. See 320.40 and also 330.40 In my opinion, the use of anti-short bushings does not create boundary between a good job and a poor one. Just my opinion.

As the others said, nice looking work Bob. [Linked Image]

Edited to add code references.

[This message has been edited by Ryan_J (edited 03-28-2004).]

Thank you Ryan.

While I would be quick to point out the same thing Ryan did (Red Heads not Required) when out on the job I just can not bring myself to leave the red head out even if it means a walk back to the stock area to get some for just one MC termination.

Always have used them and probably always will.

It seems like very cheap peace of mind to help prevent shorts similar to this.

Friday a 277 volt switch box blew up when energized for the first time with the device installed, the circuit has been locked out.

I have not checked it out for a cause yet, I did see the destroyed wall mount occupancy sensor and the blackened wall paint, I will check into it tomorrow and let you know what I find.

My feeling is that the load side wire from the occupancy sensor got pinched when installed, the circuit had been working before the wall sensor went in.

Bob

yes i do know that but i think all good electrician use them!
If you are on my job you will use them and
that is all there is to it.
But just for the fun of it why do thay come
on the roll?
All yes and what about 110-3b 110-7 110-12
If thay come on the roll just to throw them out (i don't think so)

NEC is the MINIMUM standard. There is a difference between meeting the minimum and going the extra mile for quality.

Nice work iwire.

If we hadn't sold our $750 digital camera at the last garage sale for $30, I'd submit some photos too. hopefully they'd measure up.

Big guy: None of your references apply. 110.3(B) pertains only to the listing requirements. The last time I read the UL white book, they are not required on MC cable. As far as neat and workmanlike goes....come on [Linked Image]

. I'm not saying they are a bad thing, in fact I used to use them myself, but they aren't required.

Nice looking work Bob. Interesting how you pull the cable before the walls are up. Never seen that done on a large scale before.

Could you send those drywallers to Ga? [Linked Image]

iwire your work looks good and you use anti-shorts that is what i think
ryan would you explain 110.7 to me then and why the mc come with anti shorts

Thanks "Big Guy"

I do not see that 110.7 requires Red heads, 110.7 tells us we will not intentional leave any short circuits, at least that is how I read it.

Not using a redhead does not guarantee a short circuit, it does make me wonder if there will be one.

Tradition is why the makers send redheads. [Linked Image]

Here is a NEMA statement on Anti-Short bushings.

You can download it from NEMA here.
NEMA Bulliten 90 Use of Anti-Short Bushings (pdf)

Quote

NEMA ENGINEERING DEPARTMENT BULLETIN No. 90

August 14, 2002

Use of Anti-Short Bushings for Terminating Type MC Cable

There has been much confusion within the Installation and Inspection communities regarding the use of anti-short bushings for terminating Type MC cable. The confusion stems from the fact that some MC cable manufacturers include anti-short bushings with their cable. The inclusion of anti-short bushings with coils or reels of MC cable is based on historical practice relating to the requirements of 320.40 of the NEC, which mandates the use of anti-short bushing or its equivalent protection for Type AC Cable.

Fittings used with Type MC Cable are required to be listed per 330.40 of the NEC. NEMA supports the use of listed fittings for MC Cable. The design of these fittings may or may not include an insulated throat however, they are required to be provided with a smooth, rounded end stop so that the metal sheath of the cable will not pass through and the wires will not be damaged in passing over the end stop. Whether or not an insulated throat is part of the listed product, these listed MC fittings do not require an additional anti-short bushing. Anti-short bushings that may be supplied by MC Cable manufacturers are for optional use by the installer, however they are not required.

ROP #7-116 from the May 2001 Report on Proposals (ROP) for the 2002 NEC was a proposal seeking to require anti-short bushings on all MC Cable termination installations.
The following is an excerpt from the Panel statement rejecting the proposal:

Anti-short bushings are not required for Type MC cable in accordance with the listing for the product. The termination fittings approved for use with Type MC cables are designed such that the wires will not come in contact with the cut edge of the armor; the throat of the fitting is small enough to prevent contact with the armor. Type MC termination fittings perform the same function for Type MC cable as Type AC terminations plus the anti-short bushing do for Type AC cable.

NEMA supports the uniform adoption and enforcement of the NEC and recommends that local Authorities Having Jurisdiction follow the requirements of NEC Section 330.40, Boxes and Fittings for MC Cable. Section 330.40 requires that the fitting be listed, but does not mandate the use of an anti-short bushing.

Distribution List:
Standards and Conformity Assessment Policy Committee
Codes and Standards Committee
NEMA Executive Staff

Iwire, Thanks for the NEMA statement. I have been looking fr something in writing that states that anti-shorts aren't required. BTW, I still use them.
Good looking job. One question. Are you doing a lot of strictly MC commercial jobs in your area? We are still using mostly EMT here.

Darn good job, Bob!!!

As to the clean jobsite, if the place becomes messy and no one from the GC's staff can / will sweep / clean up, I have no problem grabbing brooms / shovels / rolling dumpbins / 1-2 Apprentices for additional help, and cleaning the place up.

Can't stand a messy workplace!

Scott35

110.7 Insulation Integrity.
Completed wiring installations shall be free from short circuits and from grounds other than as required or permitted in Article 250.

ok that is what it says
do you know how many time's i have had to move a 2x4 trofer and BOOM
IF you don't use them it will happen
what do i know I just do this for a living

Bob,

I noticed that you are using the deep boxes for the LV wiring also. When I took a LV course the instructor said to use rings only, so as to leave enough room for all the cables and to maintain the bend radius. He was talking about at least a foot on all the LV cables. Your thoughts?

PS, nice looking job.

Jim

Jim, normally I would use rings.

This one as a matter of fact.

[Linked Image from erico.com]

This one acepts 3/4" EMT.

Job specs called for boxes, the engineer knows best. [Linked Image]

Of course at the office cubicle Data drop locations the plans called for a 2" EMT into a 2 gang box. [Linked Image]

The Data contractor is doing fine with these and they are certifing the work. [Linked Image]

Bob

Looks good Bob. I too like a clean jobsite. Makes life easier for everyone. Unfortunately it seems to be the exception rather than the rule. Big Guy why the hostility?

Bigguy,
Do you move the troffer while it's turned on?
We do this for a living as well, and I think the general consensus has been that although not required, we still use the bushings.
I contacted a couple of manufacturers about this about 2 years ago, and found out that they weren't required. I don't think I've put in 1 piece of cable without them since, tho. [Linked Image]

Quote

One question. Are you doing a lot of strictly MC commercial jobs in your area? We are still using mostly EMT here.

Almost all jobs here go out to bid with EMT specified.

Then the customer gets 'sticker shock' and value engineering starts.

Cables are king here in MA, MC, NM, AC etc.

On jobs with literally miles of MC, what technique do you use for cutting the stuff?

For smaller jobs I just use the rotary cutters, but these leave an ugly sharp point that screams 'fix me'. Cutting this point off with kleins seems to make things worse. The only solution that I find acceptable is to use the red heads.

Knowing that the red heads are not required, I wonder if for UL testing they have some sort of uber-clean cut on the end of the armor...I could imagine a tool which makes a nice, clean, de-burred edge giving vastly different results in terms of safety versus a standard saw cut.....

-Jon

The only acceptable method for cutting the armor of MC/AC cable is the rotary cutter.
At least with Alflex and AFC, it's part of the listing.
I'll try to find substantiation.

Inspectors here even ask electricians what they used to cut the cable when they inspect the jobs.
(This subject came up at a recent IAEI meeting)...S

electure, Thats is a new one on me, how I strip the armor has never been asked of me by an inspector.

I would be interested in anything that says we must use rotary cutters, not being a wise guy, I just have never heard that.

I still use a hack saw if closer that my roto splits, other guys have a fancy pair of dykes they use to kink and cut the armor.

I also run 4/0 - 4 MC, sorry I do not have a 2" pair of roto splits. [Linked Image]

Some of the guys have roto splits that take up to about 1" OD cable.

Bob.

Bob,

Very, very nice looking job! Excellant work. [Linked Image]

Jps1006,

Please give me your home address. I want to come to your next garage sale! [Linked Image]

Big Guy why the hostility?

I did not think i was being that way.I am sorry if i hurt somebody's feelings I DID NOT MEAN TO
Next question about the lights
sometimes i move them with power on
there seems to be more of a problem with
277 volt than 120
I would also like to say that anti shorts
are a big thing to me not just because of fixing old work but on new job's also
If my job gets a call back to fix something
like this it make's me look bad. I can't watch
everybody but something little like putting
anti shorts in twisting wire's make's my life easier and by the way all code articles
that i said was in the defense to use
anti shorts not the general work that you did. just to clear that up ok

BIG GUY

Bob,
I've not found a requirement yet.
Just a manufacturer's suggestion, probably not enforceable. Kinda like the red heads [Linked Image]

Try page 50&51, or screen 27 of 33 at www.afcweb.com/pdfs/afcpocketguide.pdf
(This site has a lot of good reference material, just in case there's something else that we never heard of [Linked Image]

)

It absolutely has been asked by inspectors in more than a couple of jurisdictions around here.
I don't believe that they mean 4/0 MC.

Seems funny that you'd walk all the way to the truck for a red-head, but not 3ft for your RotoSplit. [Linked Image]

I'll keep looking for some requirement...S

Hi Scott,

Quote

Seems funny that you'd walk all the way to the truck for a red-head, but not 3ft for your RotoSplit.

Fair question [Linked Image]

to me it is a non issue, I was brought into the trade using a hacksaw, I was taught to use a hacksaw for this in trade school (1981).

I do not know of anytime I have hit the conductors, (a thumb, the back of my hand [Linked Image]

)I have seen Rotosplits hit copper.

When using Rotos the armor is held straight, when I use a hacksaw I put a good bend in the cable forcing the conductors away from the cut.

Most of the new guys do not even know it can be done with a hack saw and are surprised when I am faster with my saw.

So what I am trying to say is, I like to use Redheads no matter how I strip the armor but I will strip the armor anyway I can and feel good about it. [Linked Image]

Unless they change the rules. [Linked Image]

Bob

Mean Gene,

I don't want you to feel I'm over selling when you finally get a chance to see the merchandise. The camera was expensive because I bought it when they were first coming out. Kind of like trying trying to get more than $100 for my P3 500 mhz Compaq that cost me over $2000.

Still you're more than welcome under one condition..... you bring an empty truck. We're selling by the pound this year. Gotta make room for the new baby in August.

Well Jps, congratulations on the new baby! I have one due myself on April 16th (our 11th).

There was a proposal to the 2005 for the requirement of these bushings on type MC cable. The CMP shot it down by a vote of 12-0.

Mean Gene,

Have you figured out whats causing all these kids yet? Hehe.

Seriously ,congrats and may you get some good helpers from the deal.

That is some pretty work Bob. And it is nice when the GC has clean up guys police the place. I think the dry wall people might be federal undercover agents or something though, I doubt if they're really dry wallers. [Linked Image]

I recently encountered work like this....and with approximately 300 openings in the walls, they only missed six.

This contrasts with another job- where one side of the building was done professionally, while the other side had the boxes packed with mud. Obviously two different guys at work!

Great thread Bob!,
Good to occassionally see the other side of the story.
BTW, nice cable work too, it's a shame to have to hide something that neat in the walls. [Linked Image]

I ran AC by the mile when I lived in CT. Here in central TX it's not allowed, so MC is used. Most everywhere I've seen the bushings used too.

I've never had a short due to moving a troffer, but once had to investigate after the HVAC guy felt a little tingle of current from the troffer. (Seems the snap-fit of those knockout plates doesn't really assure a good ground, and don't even get me started about the guys who just wrap the wire around the screw and don't tighten it down!)

What gets me (AC back in the day had steel armor, and yes, I learned to cut it with a hacksaw, circa 1994), is that MC with the aluminum armor stretches so easily. You install it carefully, and then someone comes along and bashes it. Then the armor uncoils, and all that is left to protect the insulation is that wrap of clear plastic that supposedly obviates the need for bushings. If that's OK, then what is the armor for? I think that's why they outlawed NM in high-rise construction, right?