Owner-builder electrical questions

Specific Inspection Topics Electrical Inspections
1

Building a house with help from two friends who disagree on how to wire things. One worked as an apprentice electrician in the 70s (and is dyslexic) and refuses to do any actual work (or go to the house) but is doing the circuit design, and the other has ‘read the code’ and knows how to wire things but I am not sure he knows what is acceptable to an inspector. It is my house and I am feeding wires, fetching tools, and trying to make sure things are done right.

First question - how would an inspector like the main panel wired?

Square D QO 100A panel, with 10 spaces for breakers on each side and I think it is 8 screws on each side at the bottom and 8 cutouts below those (places to punch holes). Each breaker will accept two wires. The box is installed with the numbers upside down because it is on an enclosed porch rather than a basement, and I labelled breakers ABC… on the left and JKL… on the right from top to bottom. The cables from the house are coming in through the bottom (through crawlspace then through a cellar under the porch). I forget where the main cable comes in - I think also the bottom. I could post a photo. We have one 2-pole breaker on each side and spaces for 8 1-pole breakers.

Friend No. 2 says you can put only one wire through each cutout and if you run out of cutouts on the bottom, you have to use the cutouts on the top. Friend No. 1 says to put two wires through each cutout (most of which are 1/2" but some can be 3/4").

Friend No. 2 has been putting the white (neutral) and bare (ground) wires from one breaker into one ground screw and says you cannot put more wires into one screw.
He was also bringing in the cable on either side of the box and then attaching the black wire to a breaker on either side randomly and the white and bare wires to a grounding screw on either side (which meant long black wires looping over the top or bottom of the area of breakers). I noticed this after he ran out of grounding screws on the right side which had very few breakers in use, and I made him redo everything so the black, white and bare wires ended up on the same side where the cable entered the box (from the bottom). There are now large loops of wires on either side but nothing crossing sides.

Friend No. 1 says you should ground the white wires on one side of the box and the bare wires on the other side. If this is the case, do the white wires go on the left or the right side? (Screws are below breakers since box is upside down). Friend No. 2 says all the panels he has seen have white and bare wires from one breaker combined in the same ground screw, and this is simpler to wire and to understand and if he has to redo it some of the wires may be too short to reach the other side.

Friend No. 2, because he thought there was only one cutout and one ground screw per breaker (though the breakers will take two black wires each), removed the No. 14 wire from the first breaker and attached it to a junction box (to which four other No. 14 wires will be attached for a lighting circuit) and put in a No. 12 jumper from the breaker to the junction box, which I made him replace with a No. 14 jumper so that the next person would have a better idea of what is going on (and which Friend No. 1 said is also code).
We will have five No. 14 cables (for a 15A lighting circuit) coming to the junction box (or we could have one go to the breaker if we can put two cables through one cutout and use one ground screw for both pairs of white and bare wires).

A circuit tester shows that all our outlets are properly wired and everything seems to work, but I would like the box to look more logical and be more predictable for anyone working on it in future, as well as passing inspection.

Where would an inspector like to see the cables, black, white and bare wires relative to the breakers? I may hire a licensed electrician to make it look better.

The cables going through the walls are also twisted - does an inspector care? We eventually rigged up a broom handle over two milk crates on which to unroll the coils of cable and untwist before I fed the cable through the holes.

Second question - have I properly interpreted code regarding outlets?

(1) Tamper-resistant TR 15 and 20A outlets within 5 1/2’ of floor (even GFIC ones)
(2) AFIC TR bedroom outlets (AFIC breaker)
(3) GFIC TR outlets (or first in series) or breakers for all bath and laundry outlets, and in kitchen above counters, but not for kitchen refrigerator (even if within 6’ of stove - we put it at 67" and made it TR anyway). Supposedly older refrigerators do not like GFIC. GFIC outlets in cellar, porches, outside (two outlets required). No outlets required in attic or crawlspace.
(4) Weather-resistant (WR TR) outlets outdoors and on porches, in WR boxes.
Porch outlet boxes must resist weather when nothing is plugged in. Outdoor outlets must resist weather even when something is plugged in.

Third question:

We will be doing some surface wiring in 1/2" conduit with standard metal boxes (THHN wire from a junction box fed with romex), and also to surface boxes on the wall (wired with romex from inside the wall), with cement board walls (hard to cut rectangles, easy to cut holes). You can use 9 No. 12 THHN wires. Can two circuits share one ground in conduit?

Fourth question:

We plan to have two separate lighting circuits (15A) with 11 light fixtures on each circuit, mostly with standard porcelain light sockets into which we can screw LED or other bulbs. Is an inspector likely to object? With 100W bulbs this is only 1100W.
Are 150W incandescent bulbs even made now? I bought a bunch of 12W LED bulbs for $13 each. LED fixtures are at least $55.

Many thanks from a non-electrician DIY-er.

2

This is not a do-it-yourself forum. Hire a qualified, licensed electrician. Nobody here is going to take the potential liability of answering because you misinterpreted what was said.

3

A copy of “Wiring Simplified” may answer many of your questions and should be around $10.

It sounds like your friends could use some help.

4

After reading your entire post, it’s apparent that neither one of your friends are qualified to wire the residence, much less design the wiring diagram.

Jim provided a good reference for getting the basics, but considering the potential ramifications with regard to electrical systems, this is one of those areas where you really should hire a professional.

5

Sindi

As others have already said, this is not a dyi forum.

After reading your post, I fully suggest hiring a licensed electrical contractor. No offense, but it sounds as if neither you nor your friends have a very good understanding of what you/they are doing. Remember, you and perhaps your family will sleep in your home. That should be reason enough to pay a professional.

6

Following everyone’s advice at this forum (which backed up my opinion), we talked with a friend of a friend who is a licensed electrician (commercial) with 40 years’ experience. First one of my friends looked online for how to wire electric panels and saw it done several different ways (white and bare combined, bare with bare, or one wire per screw). Home Depot has instructions online.

He was very helpful. Said to use 14-3 cable to wire the smoke detectors, not 14-2 for power with 18 to interconnect them, and they should be on the lightning circuit so you will know if they lose power. He told us of someone who turned off his smoke detectors and his kids burned to death.

He stopped by to look at the house. We need a light over the kitchen sink with an adjacent switch (not just one in the center of the ceiling). (I got the AFCI, GFCI, WR, TR and outlet spacing over counters correct already). Outlets should be wired with 6" wire from back of box to end of wire so you can pull them out to replace them easily. Copper crimps need an expensive tool and instead of crimping with the wire stripper use wire nuts. Try to untwist the cable before putting it in the wall. Use plastic straps instead of insulated staples if you have a bunch of cables together (at the panel). He seemed to think we were okay working on our own and said he would come back again to look at further work, no charge.

He looked at our electrical panel and said we were missing the bonding screw. My partner said the inspector had him remove it because we have two panels grounded together (second one is time-of-day for hot water and electric heat).

Because of this situation, according to the owner of the city’s best-rated hardware store, we not only need one grounding screw per wire but also the white wires (neutral) need to go on the existing ground buses, and we need to add another strip (20 more screws for our 20 circuits) and move the bare wires to it. Something about neutral and ground being separated because they are not grounded together? $10.49 for any style Square D box. They also come in shorter lengths. He also pointed out that there was another short strip of screws (for white wires) next to one of the two we used, in case we put a second cable into any of the breakers (which would require another 5-screw grounding bus).

In the other panel (with bonding screw) we can put the white and bare wires any place we like, one per grounding screw (such as half on each bus). Since we will only use 10 of the breakers we should not need to add another grounding bus.

Do the inspectors in this forum agree with this interpretation of code?

7

A post at Garden Web about how to wire outbuildings with subpanels explains that the bonding screw should be left out in a subpanel because neutral bus should not be connected to ground or to the metal breaker box case. In a subpanel (which is apparently any panel grounded to another even if you have separate meters), the subpanel is not grounded to metal ground rod or metal piping, only the main panel is.
In the subpanel only the neutral wires should be connected to the neutral bus (two bus bars on one bus with 18 screws total). Our panel has no separate bus bar for equipment ground, which is typical of panels sold with main breakers in them (which we supposedly do not need but do want, since we have two meters and two services and nothing but the grounding is shared), so we should add a bus kit to the case and ground it to the metal box. The licensed electrician who looked at our box missed this and said the bond screw needed to be replaced. The hardware store owner explained how to wire a subpanel with two separate buses.

I will ask further questions at some diy forum or the hardware store.

8

DIY forum moderator said to ground the two panels separately, with bond screw in each, and neutral and ground wires could go on the same bus. Original inspector said to ground them together and remove bond screw from the second. We should probably leave it that way. The panels are touching as well as grounded together, and the other one is grounded to rod and pipe.

Square D and forum moderator said we can have two ground wires (but not two neutrals) per screw. Hardware store owner thinks this is less safe because of potential arc faulting, that inspectors prefer to see one ground wire per screw. Which do inspectors at this forum prefer?

9

Originally Posted by wblackmon http://nachi.cachefly.net/forum/images/2006/buttons/viewpost.gif
Sindi

As others have already said, this is not a dyi forum.

After reading your post, I fully suggest hiring a licensed electrical contractor. No offense, but it sounds as if neither you nor your friends have a very good understanding of what you/they are doing. Remember, you and perhaps your family will sleep in your home. That should be reason enough to pay a professional.

It is advisable to hire a qualified, licensed electrician

Following everyone’s advice at this forum (which backed up my opinion), we talked with a friend of a friend who is a licensed electrician (commercial) with 40 years’ experience. First one of my friends looked online for how to wire electric panels and saw it done several different ways (white and bare combined, bare with bare, or one wire per screw). Home Depot has instructions online.

He was very helpful. Said to use 14-3 cable to wire the smoke detectors, not 14-2 for power with 18 to interconnect them, and they should be on the lightning circuit so you will know if they lose power. He told us of someone who turned off his smoke detectors and his kids burned to death.

He stopped by to look at the house. We need a light over the kitchen sink with an adjacent switch (not just one in the center of the ceiling). (I got the AFCI, GFCI, WR, TR and outlet spacing over counters correct already). Outlets should be wired with 6" wire from back of box to end of wire so you can pull them out to replace them easily. Copper crimps need an expensive tool and instead of crimping with the wire stripper use wire nuts. Try to untwist the cable before putting it in the wall. Use plastic straps instead of insulated staples if you have a bunch of cables together (at the panel). He seemed to think we were okay working on our own and said he would come back again to look at further work, no charge.

It is highly recommended you HIRE a qualified licensed electrician and have them do the work… Is your new home and possibly your life only worth a few hundred measly dollars? If you do your roof, it may leak, do your plumbing, it may leak, but your electric, when it leaks , you lose.

In conclusion, I do not think you will find a profession inspector who will tell you what is acceptable. It is either right or wrong, no in between. No one here is going to that responsibilty IMO

10

The DIY moderator and the Home Depot “guide” are not giving you accurate information. These are not “inspector preferences,” they are code and manufacturer requirements.

No more than one neutral per terminal screw - period.

Neutrals and EGC’s (bare) cannot share a terminal screw - period. EGC’s can be doubled or tripled only if the panel is listed accordingly.

Neutrals are to be bonded to the panel at only the service equipment - period.

Neutrals must be isolated from the panel at every point past the service equipment - period.

EGC’s must be bonded to every panel - period.

Sub panels at “outbuildings” require their own GEC, such as a ground-rod or Ufer.

It sounds like you’re saving a few bucks by doing this yourself. Are those few-dollars really worth the price you might pay as the result of an electrical fire or electrocution? Do you think this unpaid commercial contractor will accept any responsibility if this were to occur?

11

Sindi , let me ask you a simple question. If your car was giving you problems, would you swing by a car lot and ask a salesman how to fix it? I dont think so. You would seek the opinion of a mechanic, someone who is skilled and knowledgeable in actual repair. When you speak to a guy at a hardware store, you are making the same mistake. He sells for a living. Maybe he is knowledgeable, maybe he isnt. You can only assume, whereas a licensed professional has at least met some type of criteria for his license and in almost all cases will be insured for damages that might arise from his work.

It is apparent that you still have many questions. It is apparent you will ask anyone for an opinion or direction from the number of questions you have. Let me put this in perspective. How tight should the main lugs be tightened? How tight should the wire nuts be twisted? How much force can the service entrance cables place on the main breaker without potentially damaging it? More importantly, how much force can the main breaker withstand? When you terminated the service entrance conductors, did you “seat” the cables in the lugs? Are you twisting the stripped part of the conductors before you install a wirenut? Maybe you should, maybe you shouldn’t, you need to know and understand BEFORE you install them. How much force can the receptacles stand when you install them into the box that is recessed in the wall? I have replaced 2 in the last 2 weeks that were destroyed when they were installed…and they were installed by a fairly well experienced electrician.

If you struggle to answer these questions, please stop. Hire a licensed professional electrician. I dont attempt to cut my own hair, nor do I perform surgery on myself.

12

Some sound advice!

@Sindi:
Jeff Pope went through the “basics”, the easy stuff to know. William took it a step further and detailed a few more things which should be known by the technician. Every other Inspector on this post recommended the same thing and that was to get a licensed, professional, competent and qualified electrician to do the work.
This part of the house system is not a DIY job, especially when your family’s life is at stake.

13

If you survive long enough to sell this house, you will almost surely spend more money to undo the nightmare you are creating for yourself when your buyer’s inspector gets a look at what has been done.

Hire an electrician to do the system. It will be safer AND save you money in the long run.

14

Thank you all for your advice. I will have a licensed electrician do the final wiring to outlets and switches and junction boxes and light fixtures, or at least redo our work, and redo the panels, after we run the wires through the walls and purchase and place everything. It is a highly custom house and we are planning locations of things as we go and this will make sure everything ends up where we want it. It is not for sale.

Square D said two ground wires per screw are okay (not two neutrals or one of each) if #14 or #12, but we were told the local inspectors do not like this.

The original inspector said to remove the bond screw from one of the two panels, run #8 wire from that panel to plumbing pipe and #6 wire between panels and from the other panel to the ground rod, and he approved of the installation by my friend who worked several years as an electrician (apprentice).

This year the local licensed electrician said to put the bond screw back and to add separate ground bar kits for the ground wires because of code changes and so we would have enough screws. I can ask the new inspector about the bond screw, and whether the #6 and #8 ground wires should be moved from the neutral buses to the new ground buses.

This same electrician checked a few outlets and said they were wired correctly except we needed a special crimping tool for copper crimps and to use wire nuts instead, and be sure to leave 6" wire from the back of the box. His only other comments were the bonding screw and ground buses.

15

Sindi, are these two service panels or a service and and another panel downstream? do you know the difference?

Instead of running all the wires just to have them removed because you didn’t understand code requirements for branch circuits, individual circuits or a variety of other reasons will only cost you money. Tell the electrician your special needs up front and save yourself the headache.

16

Unfortunately it appears you do not under stand that electrical is the single most imporant and most dangerous system in the house. You do not understand CODE and it seems if you are not doing the work that you know nothing about you will not be happy. Good luck to you with your high end electrical project. Your will need it

17

Two service panels each with a 100A breaker, fed from the same 200A service.
#8 ground wire from water pipe to one panel (without the bond screw), #6 ground wire from ground rod to other panel, #6 ground wire connecting the two panels, all these ground wires on the two neutral buses (one of which is lacking the bond screw). I will call the current inspector and ask about bond screw and whether these ground wires go on the new ground buses.

We can have a licensed electrician check that we meet code before the rough inspection, and also do the wiring of outlets, switches, fixtures and panels for final inspection. This lets us put things exactly where we want. They can be moved if they don’t meet code for some reason.

The two people doing the actual planning and work know a lot more than I do about wiring and one was an apprentice electrician for several years. I am the typist. (I work as a translator). Thanks for all the advice.

18

As an electrician and electrical inspector and have been teaching electrical classes for over 12 years.

This being said the one thing I am sure of is that if the three of you were added together there still wouldn’t be a good helper there.

I have read nothing you have posted that would meet the requirements of the NEC.

19

Just a thought, do you or your helpers know the difference between a common and a neutral?

20

That lack of knowledge and understanding in the complexity of these projects will lead to increased costs when someone has to figure out the mess that needs to be dealt with.

Sindi, the contractor works for you, You can tell them where you want the switches and receptacles and they will be installed according to code with your desires in mind. Stop making this harder than it needs to be. Let the contractor do the job and use their knowledge and skills to provide a safe system that will last many years.