Question about electrical wiring in house.

[VeeDubb]

We're looking at buying a house. Because of the age of the house 2 prong receptacles are throughout the house. But there are a bunch of 3 prong receptacles installed at various locations that are not grounded. To change the 3 prong to grounded receptacles an electrician would have to ground the entire house which means re-wiring the entire home.


The seller says they will not re-wire the entire home. The 3 prongs can be used, but they just won’t be grounded. If you have them put the 3 prong back the 2 prong then you won’t be able to use a 3 prong appliance unless you use adapters.

I guess my question is would it be safe to use the 3 prongs without grounding or to put the 3 prongs back to 2 prong?

I'm wondering if we should go ahead with buying this house.

Any advice would be appreciated.

 

[Pablo]

I'm neither a licensed electrician or contractor, but I wouldn't live in a house with electricity and no proper grounds, let alone plug in a device with a ground wire that ends up ungrounded.

Either work a deal with the seller, move on, or bite the bullet. Running wire is not the hard, IMHO it's patching all the drywall and stuff that's the biatch. But there are ways to minimize the damage...

 

[duaneb9729]

if i were in your position i would call a local electrical contractor, and hire him to take a look and see what might be required and how hard or expensive it would be to up grade the house.

then you would have the facts to make good decision for yourself.

Duane

 

[94MaxGXE]

Just make them upgrade the whole system to code before they sell it, or move on......
It's that simple....

 

[JHZR2]

how many stories? knob and tube wiring throughout?

See if the seller will give a concession towards the work, they might not want the hassle, but may provide you a few bucks.

My home is a mix of knob and tube with newer wiring in various spots. Like many older homes, there wasnt necessarily enough electrical service throughout to meet today's needs. In spots where there is know and tube or two-wire service, we either convrted the plugs back to two prong (for use with stuff like lights, vacuum cleaners, etc.), or we added grounds.

Older homes dont have insulation in the walls. Dropping an additional wire down from the box to create a ground isnt terribly hard in many spots. What I did was bought 10 and 12 gauge stranded copper wire with a green plastic sheath, then sent it from a hole in the service box down to the basement. From there, I grounded to the water pipes, which in an older house is common.

Our water pipe is grounded to an earth rod via a heavy copper conductor in multiple spots. Im not sure why they did this...

But you could do that...

JMH

 

[VeeDubb]

Thanks for the responses guys. Good insights.

JMH, the house is a single story ranch, about 3000 sqft with a full basement. Built in the 50s. I should also add that the GFIs don't trigger according to the housing inspector who used a tester.

 

[mrsilv04]

Of course the GFI's don't trigger, there's no ground.

Is the basement finished? A rewire will be cheaper if the basement is unfinished.

Has the service ever been upgraded either? Is it 60 or 100amp? If it is a 60amp, then it will need to go as well.

Where I live, it isn't allowed to put a house with a 60amp service on the market. It must be upgraded first.

Does the electricity come in overhead, or is it underground?

 

[VeeDubb]

Originally Posted By: mrsilv04


Is the basement finished? A rewire will be cheaper if the basement is unfinished.

Has the service ever been upgraded either? Is it 60 or 100amp? If it is a 60amp, then it will need to go as well.

Where I live, it isn't allowed to put a house with a 60amp service on the market. It must be upgraded first.

Does the electricity come in overhead, or is it underground?


Thanks for the thoughts. To answer your questions.

1. The basement is finished.
2. According to the housing inspection report, the service is 50amp with 120/240 rated capacity. There were also some mismatched breakers. Some were 40amp single pull and the one for the air conditioner is 30amp and the wiring installed is is rated 20amps.
3. The electrical service is overhead.

 

[Cory]

The electrical situation doesn't sound good. Some excellent advice has been given.

Consult an electrician for the cost of the upgrade and local codes in regards to the sale of the home.

Get them to fix it at least to code (may have legal advantage here) or get some money at closing.

As commented earlier, many older homes come poorly insulated. I'd consider having this looked into as well. Do they have past electrical bills available? Or you can usually go to the local utilities for that information.

Best of luck in your decision!!

 

[mrsilv04]

Originally Posted By: VeeDubb
According to the housing inspection report, the service is 50amp with 120/240 rated capacity. There were also some mismatched breakers. Some were 40amp single pull and the one for the air conditioner is 30amp and the wiring installed is is rated 20amps.


OK, if you are serious about this place, it is time to pay a qualified electrician for 1-2 hours of his time to inspect it, and to explain what needs to be done both in the short term, and what you're looking at in the long term.

A re-wire, if done properly, will be an investment in this house.

The problem is, there's plenty of people out there who think that they can do electrical work, and will do things that will work, but are dangerous. Whoever the genius was who put in the inoperable GFI's in, is a prime example. That should be a warning sign.

Why did they even bother?

 

[brianl703]

The reason the inspector's tester did not trip the GFCIs is because it tries to create a ground fault between hot and the ground terminal. However, nothing is connected to the ground terminal, so it can't create a ground fault, so nothing happens. This does not mean the GFCI does not work or is installed incorrectly.

A GFCI does not need a ground connected in order to work properly.

In fact, section 210-7(d)(3)(c) of the 1996 National Electrical Code states:

Quote:
A nongrounding-type receptacle(s) shall be permitted to be replaced with a grounding-type receptacle(s) where supplied through a ground-fault circuit interrupter. Grounding-type receptacles supplied through the ground fault circuit interrupter shall be marked "GFCI protected" and "No Equipment Ground." An equipment ground connector shall not be connected between the grounding-type receptacles.


That basically means that you are allowed to replace a non-grounded two-prong outlet with a GFCI outlet (which has a ground prong). In that application, nothing is connected to the ground terminal screw on the GFCI.

Furthermore, you are allowed to replace all two-prong receptacles connected to the "load" side of the GFCI with three-prong receptacles, again with nothing connecter to the ground terminal screw on those three-prong receptacles.

Versions of the NEC since 1996 contain the same wording, although it may not be in the same section. Seems they like to rearrange things between versions.

 

[andyd]

Open an outlet box after killing the circuit. strip back the jacket on the wire to see see the conductors. Even 50s era Romex should have a bare ground. Or if the wiring is metallic sheathed BX , then that can used as a ground. All that is needed in both cases is to provide ground connections at the panel and the outlets. The older wiring in my house had the ground wire wrapped around the outside of the jacket so that the clamp was conducting ground to the box.

 

[Papa Bear]

Originally Posted By: andyd
Open an outlet box after killing the circuit. strip back the jacket on the wire to see see the conductors. Even 50s era Romex should have a bare ground. Or if the wiring is metallic sheathed BX , then that can used as a ground. All that is needed in both cases is to provide ground connections at the panel and the outlets. The older wiring in my house had the ground wire wrapped around the outside of the jacket so that the clamp was conducting ground to the box.


+1

 

[VeeDubb]

Thanks everybody. We're going to bring in a licensed electrician to check this place out and then give us an estimate on both short term and long term electrical costs. This is why I've never liked older homes. My wife loves them, I don't.

 

[eljefino]

Originally Posted By: andyd
Or if the wiring is metallic sheathed BX , then that can used as a ground.


True but if you have a dozen outlets in a row, the last one in line is counting on a positive mechanical connection between every length of sheathing and every box... which could be rusty etc by now.

 

[andyd]

Originally Posted By: eljefino
Originally Posted By: andyd
Or if the wiring is metallic sheathed BX , then that can used as a ground.


True but if you have a dozen outlets in a row, the last one in line is counting on a positive mechanical connection between every length of sheathing and every box... which could be rusty etc by now.
absolutely, but easy to check with a meter. Old houses, lose their charm after awhile. If I had realized the trouble involved in mine, I would have bulldozed it and started fresh. The only thing my house had going for it when I bought it was its location.

 

[ethangsmith]

I've got a mix of modern Romex-type wire and knob and tube in my house. It was built in 1925. From what I have been told and have read multiple places, knob and tube wiring is very safe and reliable as long as it is not disturbed or overloaded. Since your hot and neutral wires run separately inside your walls and all places where they go through a stud or joist have a ceramic insulator, it is safe. You just have no proper ground wire, which isn't really a huge issue from what I have been told. I do someday plan on rewiring, but since it is so expensive and the knob and tube that still does exist is still in good shape, I plan on saving up and then doing it. If the house you are looking at is only rated at 50 amps, that is something that MUST be dealt with.

 

[andyd]

In a code update course I took, knob and tube was mentioned and it is fine as long as you dont touch it. As soon as it needs work, it all has to be replaced and brought up to current code specs.

 

[VeeDubb]

Thanks.
I was told by the realtor's handyman that the wire is bx with some romex.

Also, below is a description of the electrical service from my housing inspection report. I am wondering, if given all that, do I need to rewire to ground and is my service adequate?

*************************
The service wire entered a ITE Pushmatic service panel, located on the basement wall with a 200 amp and 120/240 volt rated capacity. The branch circuits within the panel were copper. These branch circuits and the circuit breaker to which they were attached appeared to be appropriately matched. The visible house wiring consisted primarily of the two and three wire romex type and appeared to be in fair to good condition.

SUB PANEL

The service wire entered a ITE Pushmatic sub panel, located on the interior wall with a 50 amp and 120/240 rated capacity. The branch circuits within the panel were copper. These branch circuits and the circuit breaker to which they were attached appeared to be appropriately matched. The visible house wiring consisted primarily of the Romex type and appeared to be in fair to good condition.

 

[VeeDubb]

And here are a few more excerpts:

**************

There were breakers installed inside the electrical panel that did not match the wires to which they were attached. Breakers are designed to match specific sized wires in order for the breakers to trip when needed. The breakers affected should be changed to match the wires installed in the panel or the wires should be changed to match the breakers depending on the need of service to either the unit, area or room. Breaker # 35 & 36 is a 40-amp single pull the breaker should be double pull. Breakers # 21 & 22 breakers should also be changed to a two pull breaker. The breaker for the # 1 air conditioner is rated at 30-amps the wiring installed is rated for 20-amps.

ABANDONED WIRING:

Abandoned wiring was found in locations or various locations of this home. In the front left basement storage room. All abandoned wiring should be removed if not needed.

A representative number of installed lighting fixtures, switches, and receptacles located throughout the home were inspected and were found to be functional. The grounding and polarity of receptacles within six feet of plumbing fixtures, and those attached to ground fault circuit interrupters(GFCI), if present, were also tested. All GFCI receptacles and GFCI circuit breakers should be tested monthly. There were GFCI protected circuits located in the pink bathroom . The present and tested GFCI's were functional. The non-functional GFCI should be replaced with functional GFCI's.

It is recommended that you install GFCI’s in the outlets that are within six feet of any plumbing device, all exterior receptacles, all bathroom receptacles and at least one receptacle in the garage for safety.

A representative number of the old two-prong receptacles were replaced with three-prong receptacles throughout the home without regard to proper grounding. Any appliance, equipment or other electrical device that has a three-prong plug on the cord must be plugged into a grounded receptacle for safety. It is recommended that you consult a qualified electrician for further evaluation. NOTE: It is recommended that the receptacles be replaced with two-prong receptacles or properly ground the three-prong receptacles.