Updating Electric Service in an Old House

[Sara]

I'm repairing/restoring a 150 year old house that was originally wired sometime around 1910-1920. The kitchen was renovated and rewired in the 1970's; the bathroom was redone in the 1960's. Those rooms are in pretty good shape as far as electric service goes, although I suppose not up to today's standards.

The rest of the house has the original knob & tube wiring. The bedrooms each have a wall sconce as the only source of electricity. The sconces all have adaptors with 2 or 3 taps (sorry, I don't know what they are called) so the sconces provide not just light but have a bunch of extension cords coming out of them.

The other rooms have 1 or 2 old nonpolarized electrical outlets each, and each outlet can receive just one plug. Most of the outlets are in the floor.

The house is constructed of double brick and most of the interior walls are single brick with a layer of plaster. An old family member told me the original electrician dug a groove in the plaster to get the wire up to the bedroom wall sconces. (I have no problem with the idea of running raceway along the baseboards or up the walls as long as I can paint it.)

The house is on a circuit breaker and there is a 220 line to the electric range in the kitchen.

The house is currently unoccupied and I have just a fire insurance policy on it, because I can't get homeowners without moving in. If I move in, my current insurance company wants me to completely replace the knob & tube in order to qualify to get homeowners insurance (and will still charge a fortune after that, but that's another issue).

Ideally, I would have the whole place rewired and bring it up to code. Realistically, I know it's going to cost an arm and a leg to do that.

My question is: under these circumstances, how much rewiring should I have done to make the place safe and have a reasonable amount of electrical service to each room?

Sorry for the long post, I just wanted to explain all the conditions.

Thanks for your opinions! Sara

[Joseph Meehan]

My suggestion is to go for it. Update everything to current code. It may be required, depending on your local code.

It will be expensive, but maybe not as bad as you think. I suggest you get a few estimates from professionals who you have checked out first. You may be surprised to find they know a lot of tricks to get the job done.

In the end it is the only way to go, in my opinion. In fact I did just that about 35 years ago in a home that was about 150 years old then. I had a friend who also happened to be a pro work with me and I did most of the work. It was worth doing it right.

[EJ]

If you change more than 25% of the system you need to bring all of it to code anyway.

[zxcvbob]

The first thing is to start looking for another insurance company. K&T is not as dangerous as they are making it out to be, and they are trying to screw you on the premiums. (My NEC book is a few years old, but it still lists K&T as an acceptable wiring method for extending existing circuits.

I would try to find a way to leave the lighting circuits alone, and add a couple of new branch circuits to provide grounded electrical outlets in the rooms.

How's your service panel? Is it 60A or 100A? I can't tell if you meant that you have an electric range, or just that the service panel has a space for a range circuit. Do you have any major electric appliances? (range, water heater, clothes dryer) Even one of these and if you do a load analysis the 60A will not be adequate. If you have no major electric appliances, 60A is probably OK, and although you'll want to upgrade it there's no hurry.

Are your walls hollow, and do you have a basement to work from? You may can cut holes in the walls and install "old-work" boxes. There are flexible drill bits you can get that are about 5 feet long that are great for running new wires in old walls. You can even use the drill bit to pull the cable back through the wall hollow.

Best regards, Bob

[EJ]

K&T is a reasonably safe and perfectly legal wiring, but it has some annoying limitations. First, it is a low temperature wiring, so you can't have any insulation in the walls with K&T. Otherwise the wires overheat and the insulation degrades. The real limit on amperage is probably around 10A, which limits your window AC to about 8000 BTUs. Many vacuums, microwaves, and vacuums draw more than that. You can figure out the polarization of the wires and replace the outlets with ungrounded polarized, but many appliances require effective ground. Your kitchen and bath do need GFCI. Also, in some homes the two wires (hot and neutral) were not run in parallel, but were run up two different walls. Any upgrade requires a lot of detective work. Outlets are few and far between and (like in my house) wall switches for lights were a rarity. (I actually have hookups for gas lamps, too, but this is another story...).

It is hard to advise OP what to do exactly, but at some point the house has so many problems, that the decision is usually made between three choices:

- sell. In many markets now is the time.

- don't change anything until it breaks. Find another insurance company.

- tear the house down to the studs. Seal, insulate, replace windows, electrical, water, telephone, install cable and Ethernet, install drywall or blueboard/plaster. Get a second job. Or third.

Good luck,

[Joseph Meehan]

zxcvbob wrote: ....

....

While I agree that K&T wiring is good and if used as intended and if it meets the needs it is safe. However considering the changes in the way we live and use power today, few if any K&T systems are up to meeting the needs of a modern household.

I suspect the Insurance company is looking at the likely fact that K&T is often abused by trying to make it fit today's power needs and that it has a disproportionate amount of problems.

I do agree that anytime you are insuring a new home or make a serious change, you should take a look at your insurance and that includes the provider.

[zxcvbob]

The K&T is only supplying wall sconces (no outlets in the rooms), and it is more than adequate for that if OP runs a new modern circuit for some convenience outlets.

bob

[SQLit]

Time to start writing letters to Bob Villa and This Old House. Does the home qualify for historical status? If the electric is this old you may need new plumbing as well. Personally I would add new wiring and leave as much as the old as you can. I like old houses. I agree on finding another insurance company.

[zxcvbob]

Did you catch the part about high premiums even if OP got rid of the K&T? That's what I mean about the insurance company trying to screw her. They use the K&T to justify high rates, but they won't lower the premiums when you fix the "problem".

Bob

[Joseph Meehan]

I could be wrong, but I don't think that is what he meant.

[I-zheet M'drurz]

I just love it when "professionals" on here step up and make it look like people in other areas of expertise are idiots, that you can get over on them like country bumpkins.

FYI: Insurance companies aren't run by idiots. You tell them that your home is 150 years old and red flags start popping up all over the place. Well, OK, a moron would write a policy on a 150 year old structure without it having updated electrical and plumbing and a serious roof/structural inspection. You seem to think there are plenty of them out there, huh?

Or are you suggesting that OP just falsify the age of the home and commit insurance fraud? That would fit right in with your "Everybody-except-me-is-an-idiot" mentality.

[Alan]

...

For the sake of convenience and esthetics, more than anything, I would rewire the whole thing. My daughter hired an electrician to do just that in a 100 year old house similar to what you describe. He put light fixtures in the ceiling of every room (and there is no attic) and numerous outlets, always running the wire behind the baseboard or plaster and his fee was very reasonable. It may possibly have been a good idea to tear down exterior walls to enable insulating them as well as making the wiring a bit easier. It can be done. The hard part may be finding the right person. She talked to other electricians who thought it necessary to use wireless switches and run wires on the outside of walls or tear up the floor to get wires to one room..

[Joe Bobst]

Add to this, safety. Also, some pros are so used to doing new house work that they may not know all the neat tricks for old house rewiring. Check references in this respect for any electrical contractor you interview. It makes it easier on you and them as well. Some shops don't like using WireMold products, for example, but it is often a lifesaver in old house situations and works perfectly in conjunction with conventional methods. HTH

Joe

[Sara]

(etc. snipped)

Thanks for all your responses! You'v given me plenty to think about.

Just to clear up a few points which I did not make clear in my original post:

- the house has 100 amp service, and an existing electric range is on a 220 line.

- my current insurance co. will indeed charge me quite a bit ($2000 a year!) after the K&T is updated. Getting rid of the K&T is a prerequisite for being insured with them at all. The insurance co. wants to restore the house to all of its 1850's glory if there is a problem, i.e. use horsehair plaster like the original to repair damaged walls. I think this is overkill.

- the walls are made of brick so running wires up thru the hollow space is not an option. However the house has a basement where the majority of the electrical & plumbing connections are made so we can come up thru the floor and perhaps run wiring behind baseboard.

The house is located in an area with plenty of housing that dates back to the early 20th century and perhaps before, so I am hoping it will not be difficult to find electricians who have experience with this kind of work.

I especially appreciate the encouraging posts from the folks who have been down this road before.

Sara

[zxcvbob]

How about putting shallow outlet boxes horizontally *in* the baseboards? [I'm making the rest of this up as I type, so one sentence will not necessarily follow the next logically] Especially if you can run some kind of flexible conduit or wiremold up from the basement and use stranded wire to wire the outlets. (Because you won't really have enough cubic inches in a shallow box, and the stranded wire is flexible enough to use in the confined space if the electrical inspector will let you get away with it.) Chisel out the plaster behind the baseboard, drill down to the basement to run the wires, and fasten the box to the bricks. Or something like that. You can also buy dark brown surface mount outlets (hard plastic, looks like bakelite) that could be fastened to the baseboards if you could figure out how to protect the wires -- probably behind the baseboards. The surface mount outlets have an old-fashioned look to them that would be appropriate in an old house.

This is not what I was talking about, but they look interesting:

Best regards, Bob

[Chris Lewis]

Having been through an "almost complete" rewire of both halves of a duplex done with K&T, a couple of comments:

1) Electrical inspectors will tell you that K&T in good condition and not abused is _perfectly safe_, and does not need to be mucked with. Most K&T is in good shape, unless it's been interfered with by subsequent DIYers. 2) Modern household requirements require more than you can reasonably expect from K&T. 3) If you upgrade anything electrical, don't use K&T. Avoid adding anything to existing K&T circuits. Indeed, if possible, reduce reliance on K&T circuits. 4) Some insurance companies are unduly nervous about K&T.

The duplex I worked on was getting a full interior tear-down, and since the walls were going to be pulled off, we decided to do a complete rewire. _Except_ for one wonderfully plastered ceiling. No problems whatsoever with leaving the ceiling fixture as K&T. We just had to ask the inspector _how_ to connect the fixture feed to the new romex circuits.

If it were me, and I could find an insurance company with a better attitude towards K&T (ask if having an engineer certify that the existing installation is in good shape _may_ help), I'd:

a) Do all wiring changes/upgrades with current techniques. Leave the K&T behind plaster alone unless it's practical to abandon it (on a branch-by-branch basis).

b) Defeat the electrical outlets on those sconces, and make them light fixtures _only_.

There are various tricks you can play with distribution boxes and armored cable that can make outlet installation a lot easier.

[Chris Lewis]

According to zxcvbob :

Heh ;-)

Here's an example of a technique we used to install outlets in walls that only had 3/4" (lathe thickness) clearance between the back of the plaster and a masonry wall, on the ground floor:

In the basement, we ran a normal romex circuit along the perimeter below the wall, with a J-box underneath each place we wanted to install an outlet. Spliced in an armored cable branch to go up thru the floor, immediately behind the plaster, to a shallow box holding the receptacle.

While in our case, the walls were off making it easier, this will also work even without tearing walls off. Possibly with a little persuasion ;-)

I'm not comfortable installing outlet boxes in baseboard, unless the baseboard is quite tall. "Kicking hazard". You'd probably still need the armor in any event.

[Sara]

Thanks Chris! Those are great ideas. I appreciate your reply.

Sara