Home inspection: live knob & tube wiring

[NetWareHead]

Very interesting thread.

I don't think it's legal to put a 3 hole socket and leave the ground unconnected, that's actually dangerous if the ground serves an actual purpose.

My bet: she will wait for someone gullible. Why do the work of hiding the obsoleteness of the house if you're going to be honest about it?

I've unearthed more electrical facts. Our city requires a certificate of occupancy for any properties offered for rent. Even if the owner intends to occupy one unit, the entire structure must carry this certificate. One of the statutes relating to electrical is that if the tenant is to pay his own electrical utility, then the structure must carry a separate feed with meter. And, the structure itself must have its own feed with meter to power devices not related to the individual units. For instance this is a 2 unit house and the city wants 3 meters & feeds. The third meter would be a "landlord" meter and would runs items like hallway lights, smoke detectors, a basement sump pump etc...

This house only has 2 meters and we have raised this issue as part of the upgrades. Waiting on the owner to show us a valid certificate of occupancy.

 

[Paperdoc]

I REALLY doubt you will see a valid Certificate of Occupancy. In order to ensure the electrical services to the house have three separate branches, and the circuits within are run separately to particular places and uses in the building, it would have to be re-wired in a major way. That job would HAVE to be done according to CURRENT code requirements, not old ones, before it could be approved by an inspector. That's the entire re-wiring job you are talking about. Obviously it has NOT been done already. It seems unlikely the current owner is willing to do that. It also seems unlikely that owner has a Certificate.

 

[NetWareHead]

I REALLY doubt you will see a valid Certificate of Occupancy. In order to ensure the electrical services to the house have three separate branches, and the circuits within are run separately to particular places and uses in the building, it would have to be re-wired in a major way. That job would HAVE to be done according to CURRENT code requirements, not old ones, before it could be approved by an inspector. That's the entire re-wiring job you are talking about. Obviously it has NOT been done already. It seems unlikely the current owner is willing to do that. It also seems unlikely that owner has a Certificate.

Well sorry for painting the picture of doubt but we just heard back from the seller's agent. She says she has a valid cert of occupancy and was approved this June. (the upstairs unit is rented and she occupies the downstairs) How they got it approved....I have no frickin idea. But if it is valid then we cannot fight it and cannot ask for a third landlord panel. Of course, I will be receiving a copy of this valid cert while we move forward.

The seller has approved my request for a thorough electrical inspection though and Im trying to make that happen this week. Spoke to an electrician today and he mentioned there are 2 conductor armored or sheathed cable that do not included a ground (think bx or romex but no ground cable) that does not carry the dangers of k&t wiring but is still out of code nontheless. I beleive he said somethign that grounding only started to become code around here in the 1960s. If that is the situation, then a whole house GFCI breaker or GFCI on each circuit will solve this problem. Hearing this has given me a little bit of hope and will be something the seller willl be able to swallow.

He will pull the outlets out of the wall and if it is in fact k&t wiring, he will write an estimate for rewire of the affected circuits. This will be the worst case scenario because the seller may walk away from this deal or I may because of the cost involved.

 

[Paperdoc]

Yes, I've seen three types of BX cable over the years. The early type had only two insulated conductors inside the spiral metal jacket, but the metal jacket itself is Grounded. That is because at the fuse box the main Ground lead out to a solid earth Ground (like a water supply pipe) connects to the chassis of the fuse box, and all BX cables are supposed to be connected to that box by the fitting that grasps its end as it enters the box. Now, IF the BX cable at the other end of the run is fastened to a metal device box, then that box is Grounded. And almost all outlet devices connect their metal mounting bracket to the Ground terminal of the outlet. So it is possible for this older type of BX cable to provide a Ground connection. However, it is not guaranteed, and that's probably why this cable type does not meet code in your area.

The second type of BX I've seen adds inside the spiral jacket a flat galvanized metal strip that is used as a Ground conductor. The current third type has replaced that metal strip with a proper bare copper wire of the same gauge as the Hot and Neutral lines, and this is a good Ground conductor.

You should be aware that a GFCI device is not the same as a Ground conductor system. A GFCI device does NOT provide any Ground connection at all. What it does, in essence, is to compare constantly the currents flowing in the Hot and Neutral lines on the circuit, which should always be equal. If they differ by more than some small amount (I think 5 mA, but I'm not sure), the GFCI shuts off the Hot supply on the basis that there is some leakage of current to an unknown place, possibly a person who is being shocked. Thus this device DOES provide some of the safety features of a Grounded wiring system. So it is commonly used as a substitute in older structures with no Ground wires already installed because it's cheaper than re-wiring completely. And that substitution IS allowed in many electrical codes.

 

[crashtech]

Yeah, the BX that I have been using for certain apps is 3 conductor, in my case what they call 12/3, which is overkill for many things but since they sell it by the 100' it certainly comes in handy for many different purposes. Like Romex on steroids in a way.

 

[Tommy2000GT]

My house has newer main panel and subpanel with breakers. But it is hooked up to the existing knob & tube wiring. The oulets are 3 pronged but have no ground wires. The sticker on the panel says it passed inspection but I don't know how.

So now I'm having my entire house re-wire the correct way.

 

[natto fire]

Couldn't you just rewire it yourself? I think 12/2 w/grd is only $50 or $60 for a 250 foot roll. Probably wouldn't take more than half a dozen rolls, plus outlets can be bought in bulk for well under a dollar each. (Hell, if you want brown outlets, I have a few dozen I got at an auction that I'd just give to you if you were nearby.)

Buying wire and fishing it into walls/ceilings are very different animals. Not to mention the neutral/grounding difference, which is a big mistake I see a lot with handyman repairs.

This scope seems pretty straightforward, but electrical work can turn into a nightmare if not done properly.

 

[NetWareHead]

Update:

The seller made it quite known to us to that knob & tube was a moot point in her mind. In fact she denied it even existing which came to a shock to us given how it is just hanging from the basement ceiling and a simple touch with a electrical contact tester proves it is live. She gave us an entire spiel about not making enough $ on the sale, went as low as she could go on the selling price blah blah blah. The house has both units rented, is in "perfect shape", has a certificate of occupancy and is insured so if it is found, it is on my dime to remove it.

So she grudgingly permitted (and of course let us know it was a stupid idea) the more thorough electrical inspection and the electrician confirmed the existence of k&t in both attic and basement. Coincidentally, the electrican I chose ( who has done considerable work for us) happened to be the seller's electrician as well which he disclosed prior to the inspection upon arriving to the house. He drew up an estimate and found all of the overhead lighting on both floors was connected to k&t wiring and noted which outlets needed to be converted to a true grounded circuit. The house has original tin ornate ceilings (from 1890!) and horsehair plaster lathe walls so the estimate was jacked up a bit to deal with this difficulty. I had asked that the ceiling be preserved at almost whatever cost (since she would be paying I'd rather have the electrician make a hole we can later patch in the walls rather than the irreplaceable ceilings, plus with enough mud + work, the walls can be restored a heck of alot easier). Total cost to replace 2 circuits was $1800 and the rest of the house was using up to date wiring.

We still did not think she was going to pay so my realtor did some digging. Seller purchased the house 3 years ago and in the seller's disclosure she received from previous seller, there was a note about live k&t. In her disclosure to me, she failed to mention it. Using this technicality, we found her disclosure as having serious problems with not telling the entire honest story about the property. Plus we discovered a man living on the first floor who claimed to be a "paying tenant" despite her disclosure listing the first floor as unoccupied. Another ding.

She apologized profusely which was somewhat nice to hear after all of her bullshit responses and claims she "spaced it" (read: totally forgot about it). Her agent was probably pissed about it and advised that she would have to disclose it if she wanted to keep selling the house and it was just best to agree to reduce the price of the house by the amount listed in the estimate. End result is that I get the house for only $200 above my offer price. My appraisal just happened and if all passes by the mortgage company, we close on the 17th.

 

[iamwiz82]

To me the lying was a bigger deal than the K&T. I would have walked because you have to assume she lied about other things on the disclosure.

 

[NutBucket]

But it sounds like he got a good price?

 

[NutBucket]

My house has newer main panel and subpanel with breakers. But it is hooked up to the existing knob & tube wiring. The oulets are 3 pronged but have no ground wires. The sticker on the panel says it passed inspection but I don't know how.

So now I'm having my entire house re-wire the correct way.

The panel upgrade passed inspection. They don't check the rest of the wiring when you pull a permit for a panel.