JLatimer

Does anyone have experience with Insurance companies and Knob and Tube wiring? What do they require to make you eligble for insurance? I hear horror stories where they require evidence of every knob and wire removed from inside the walls.

I have a few runs still connected to lighting and the insurance guy is coming tomorrow to assess my house. I figure with my luck, after their visit I will have no fire insurance.

NSXNEXT

iTrader: (2)

Found a few site for you to look at. My opinion is to speak to a licensed electrician who has done the conversion.

I spoke to my Dad about it and his comment was that as long as you don't add new circuits/wiring onto existing K&T wiring, it's ok. Not sure if that's the case with you.

http://www.taunton.com/finehomebuild...ges/h00160.asp

Old wiring and the code
When you upgrade old wiring or remodel your house, you’ll have to meet the latest electrical codes. Here are some important code requirements, based on the National Electrical Code (NEC), pertinent to upgrading old wiring.

Size of the service -- The NEC requires a minimum service size of 100 amps. When I install a new service, 200 amps is the default. Usually only very large houses (4000 sq. ft. or more) require more than 200 amps. I run the service-load calculations to determine this (“Installing an Electrical Service,” Fine Homebuilding #150, pp. 78-85).

Converting nongrounded outlets to grounding -- It’s no longer permissible to ground to the closest metallic water pipe. The NEC allows a separate ground wire to be run to an outlet to provide an equipment ground. The added wire must originate from the panel ground bus, and it must closely follow the current-carrying conductors of the circuit. If you’re going to run a wire all the way back to the panel, you might as well run a new cable with ground.

Boxes -- Old fixtures sometimes are attached to framing with no electrical box to contain the connections between building wire and fixture wire. The boxes that were used later typically are too small by modern standards. Boxes must be part of a new installation. Old boxes usually need to be replaced to meet code. See “Rough Electrical Wiring,” (Fine Homebuilding #144, pp. 76-81).

Specialized circuits -- To meet the demand of modern energy uses, the NEC requires installation of several specialized heavy-duty circuits. For instance, the NEC mandates a minimum of two 20-amp circuits to serve kitchen-countertop outlets, a 20-amp circuit for the laundry, and a 20-amp circuit to serve bathroom receptacles. Requirements like these have to be met when making changes to the wiring in these rooms or areas. They’re smart to make pretty much at any time.

Knob and tube -- The NEC prohibits burying knob-and-tube wiring in thermal insulation for a couple of reasons. First, thermal insulation traps the heat created by current, causing the electrical insulation on the wires to degrade and eventually fail. Second, it increases the chance that someone moving around in an attic will damage the wiring because they can’t see it. In adopting the NEC, the State of California reviewed records for any evidence of fires caused by knob and tube in thermal insulation and found none. California and other jurisdictions across the country consequently have softened this prohibition. The California Electrical Code allows knob-and-tube wiring to be surrounded by thermal insulation if it’s inspected by a state-licensed electrical contractor and found to be in good condition, and if a notice is posted in the attic warning of hidden wiring. If you have knob-and-tube wiring in your house, check with your local building department to see if it can be used in thermal insulation.

System grounding -- System grounding protects your house and its wiring from energy surges like lightning strikes and high-voltage power-line contact with local distribution lines. The NEC’s requirements for system grounding have changed considerably over the years. This is a big safety issues with residential wiring. When upgrading a service, be sure that the system grounding is brought up to meet requirements in your area.



http://www.codecheck.com/q_a_electric.htm
There is no longer an easy way to install an equipment ground with Knob and Tube. Until 96' codes it was okay to ground to water piping at any convenient location. Since 96' you have to take equipment grounds all the way back to within 5ft. of the main grounding electrode. Two pronged wiring is only a problem where you have appliances that require an equipement ground(3 prongs).

2 prong plugs that are located in shock hazard areas(plumbing, concrete floors and soil) can be replaced with ground fault circuit interrupters(they can protect against shock even when an equipment ground is not connected).

Left alone, knob and tube wiring is a safe and reliable system. The problems with knob and tube have to do with later day modifications and additions that were done by unqualified installers.

A further caution about house wired in the twenties: For about 8 years during the twenties it was permitted to fuse and switch neutrals(now strictly forbotten). This makes for some shocking experiences for young electricians who havn't been wisened to this aberration in the code.

Furthermore, because the neutrals might be fused in a 20's house one can easily think there are twice as many circuits as there really are.

A sign that work was "boot-legged" by underqualified installers is if you see knobs installed on the underside of floor joists in a crawl space or on the top of ceiling joists in the attic. This was never to
code and is the sign of amateur work. Knob and Tube wiring is designed to be installed in the concealed spaces between joists. If you peek into a crawl space and see wires running under joists the system probably needs to be rewired.

I havn't "worked with the tools" in a while so can't begin to give you price estimates of such work.

In the late 30's when household appliances started to take hold, systems were often upgraded with a type of cable assembly called Armor Clad Cable(commonly refered to as BX). 2 prong outlets that are fed with BX cabling can usually be ground very easily because the metal sheathing of the cable is an acceptable grounding path.

Scottman111

Let us know how this went JLatimer, I'm curious now And your house is obviously old, do you know exactly how old?

I'm definitely no expert on knob and tube, I've helped my boss a few times and done some of my own work with it. But you say you only have a few runs, why don't you change them out? I know that's easier said than done, but if it's causing you problems it might be worth the time Let us know what happens...


Oh and nice post NSXNEXT, there was a lot of stuff in there I didn't know.

JLatimer

I will keep you updated. The inspection is later today and I figure I will have to wait for the insurance company to give me the results.

Most of the cast iron fixtures in the house are stamped with 1914 or 1915 so though the exact age is unknown I figure it is around 90 years.

I am planning on selling soon and moving to a smaller, lower maintenance home so I will probably just replace the runs anyway to help resale. I just wanted to avoid poking holes in the walls everywhere.

Scottman111

Ahh I see. Good luck, and good idea on replacing it. People have a lot of misconceptions about knob and tube so I'd say your better off just upgrading.

Again, good luck and I hope the inspection goes good.

JLatimer

Well that was the worst inspector I have ever seen.

Most inspectors are equipped with a tool belt. This guy only had a flashlight and a pad of paper. This guy was inches away from the knob and tube wiring and never saw it - I honestly did not hide it it was in plain sight - I did everything except say "look at the knob and tube"! When he is done he says we have no knob and tube on his report.

I am still replacing it, but now I am off-the-hook from the insurance co.

I am missing a railing on my deck that they have a problem with though. :duh:

JLatimer

Almost done replacing the knob and tube. I am at about 20 holes in the walls, with half of them being just large enough to get a fist in, and a few smaller ones. It has gone well, and was able to make a few improvements along the way - a 3-way light circuit, additional outlets, and a light switch in a room that didnt have a switch. Of any home reno work, I like electical the best.

No tickles either

But an update on the insurance thing - I dodged the k&t bullet, but apparently double brick homes are very expensive to insure - they doubled my premiums. The basis is that replacement coverage says that they have to rebuild with double brick - and not just any bricklayer will do double brick. My 220k house will supposedly cost 345k to rebuild.

Scottman111

Sounds like your making good progress You know your doing good when you haven't been tickled yet

How much more time do you have to go? And did you plan your new switches and outlets before hand, or did you just decide to add them after you started the re-wire?

And that sucks about your insurance premiums :shakehead I guess there is not way to get around it?