How dangerous is knob and tube wiring?
By the standards of the day it was adequate and worked quite well. I have run into quite a bit of it during renovations and never saw an installation that was truly dangerous. The biggest problem it presents today is that the rubber insulation has typically become brittle.
Do I have knob and tube wiring?
If this house definitely appeals to you, I'd check it out further. You can write a clause into your offer that says you won't buy unless you can obtain insurance for the house at a reasonable rate, so that gives you an out. Try checking at city hall for any permits that might have been issued for work on the house. If a new panel was installed, there should have been a permit for that work in most municipalities, and the permit should give some detail about what work was done. My guess, since there is only one outlet per room, is that there's a new panel but no new wiring except around the panel, that there is still the original knob and tube through most of the house. Many houses have such a combination, where people updated part of the wiring or added on without redoing the whole house. 100 amp service is barely adequate for most houses these days, and one outlet per room doesn't cut it at all, from a safety or a convenience standpoint. Unless the homeowner has a memory problem or is one of those people who's completely oblivious to home maintenance issues, they should remember what work was done, or have the bill for it. If this house is otherwise suitable and is on your short list, I'd have an inspection done, by a home inspector and ALSO by a licenced electrician, who should be able to give you an estimate of what it would cost to bring the wiring up to modern codes. This gives you a negotiating tool for buying the house at a price that reflects what needs fixing. Re-wiring will be expensive, but the price you pay should reflect that, and it will be cheaper in the long run than paying exorbitant premiums for years because of the knob and tube, if you can insure it at all.
Do houses built in the 50s have knob and tube wiring?
Seriously interested in a house that was built in 1951. Its an estate sale and a lot of stuff is outdated, and my concern is there may be knob and tube. But did they use knob and tube still in 1951? Everywhere I look says that they stopped using it in the 30s but I have recently viewed houses built in 1946 and they had knob and tube.
How do you know if you have knob and tube wiring?
Knob and tube is used within West Virginia and in many places with elderly homes. I replace all the time to it. I'm an electrician and also a residential construction contractor. It IS a truly fire hazard. The wire is aluminum and is undersized for the amount of current that passes through it. I have actually been burnt by it after it had been away for one minute. The most peculiar problem with it's that people replace their previous service panels using models and don't upgrade the cable. The insulation on the wire falls leaving bared cables. They're aluminum wires and as the days go on by, and so the corresponding metals pose problems, the majority of the new outlets are made to be used with aluminum wires.Replace knob and tube wiring
I have knob and tube wiring how do you ground it?
Old knob and tube wiring is safe as long as you dont mess with it or try to connect additional circuits to it. If you need additional circuits in your home, consider a total rewire with new romex wiring, new electrical panel with breakers and a new grounding system. All of the new panels, wiring and grounding will be covered in the price of a new electrical service. However, if you are just replacing outlets, this is very easy to do.Do not ground the neutral wire as it is the path the electricity takes back to the source. Electricity has to have a path to the device and a path back to the source from the device. We call the device a load. if you interrupt this path from the load back to the source, you have a short circuit. This will cause a fire.You may replce your outlets with the nongrounding type, which will have only two openings in the outlet, compared to the grounding type which has three opening, the third opening, being a ground. If you need a grounding type outlet, you are permitted to install a feed through GFI outlet in the first outlet on the circuit. Say for instance, your front room has one circuit running to all the outlets in that room from your knob and tube in your attic.Find where the power comes from the attic to the first outlet and install the GFT outlet. From that outlet, you may install romex from there to all other outlets on the same circuit. That may be a problem pulling romex to all other outlets. To hook up the GFI outlet, install the knob and tube in the holes that are labeled line. The romex will be installed in the holes that say load. the ground wire from the romex will be installed on the GFI outlet under the green ground screw. A GFI works on the principal of electrical difference between the hot wire and the neutral wire. When there is about 4 milliamps difference between these two wire, the outlet trips, saving someone from getting shocked.If you need any more information, i would be glad to help, just email me. Good luck
What are the concerns about Knob and Tube wiring?
Knob-and tube wiring is very common in older homes, and so is somewhat controversial. However, having knob-and-tube wiring in your house isn't necessarily a problem and in actuality, it is not poor to modern wiring in various ways, since many believe. Understanding knob-and-tube wiring and its problems can help you determine whether or not it needs to be replaced.One of the main differences between modern wiring and knob-and-tube is that the black and white cables are conducted separately and so are spaced several inches apart in knob-and-tube wiring. Yet another distinction is the wire insulation. Modern wiring is coated with plastic while knob-and-tube uses rubber. The breakdown of the insulating material over time around knob-and-tube wiring is often the main reason it's replaced. It is vital to note that this is the consequence of overheating or mechanical abuse.The fact that the copper wire used in knob and tube is larger diameter compared to that in the modern cable is an advantage for both knob and tube. Bigger cables stay cooler as electricity flows through them. The simple fact that the wire is older and it has been in service for several years is still actually a disadvantage of knob-and-tube, naturally. Yet another is not having a ground cable, which creates an emergency path for power that can help avoid shocks. Modern cable comes with a ground wire, knob-and-tube does not.knob and tube electric
How safe is the old knob and tube wiring?
Knob and tube is the original wiring used in not only homes but theaters and other things back in the late 1800's and early 1900's. It is safe if in good shape and it is separated from hot to neutral so it cannot short out like romex wiring. It does not have a ground system (there was no grounds back then in this type). The adapters you are talking about are not actually grounding anything that needs to be grounded if they are just plugged in to a two prong outlet. There are no ground wires in knob and tube even if it is a metal box which it is. (that is what they used then). Many insurance companies will ask for an inspection of the house wiring if they do know it is knob and tube wiring. It must be on a 15 amp breaker and cannot have kitchen wiring on it, laundry receptacles on it, a furnace on it. any heavy appliances otherwise. They may ask for it to be replaced through out the attics, basements etc. where it is visible This can be a rea tough job and messy as well. I would at some time try to get you some estimates to have a contractor come out and look at it for you and see what they recommend, insurance companies may frown on it but they know it has lasted for over 100 years in many homes and has done its job. So many homes it seems have electrical fires what many people do not know that an extension cord is dangerous if used for long term and yes this is an electrical fire, not necessarily the house wiring but still an electrical fire by insurance reasons and fire Marshall's will tell you the same thing. People who use 100 watt or larger light bulbs in 60 watt rated sockets have fires and it too is an electrical fire, as well as portable heaters etc.. Is it safe, Maybe ? but it should be checked to make sure and it has to be on the proper size fuse or breaker. and nothing that requires a ground that could cause a shock or personal injury is not on it as well.
Was Knob and Tube wiring still used in 1950 in San Mateo county?
Our house in Redwood City had knob & tube wiring, built in 1958. I've torn out and replaced virtually all of it, but it actually was not badly done. Clearly very labor-intensive to install: splices were wrapped, soldered, and taped; ceramic tubes threaded on where wires crossed, and sleeved with some tarred fabric tubing where it needed extra protection; some circuits had the wire hand-painted (!) red after install for identification (?). I trusted the original knob & tube far more than the hackery that the subsequent homeowners installed.However, the old insulation had become very brittle, and what few ground conductors were in place were haphazardly run to the nearest copper plumbing pipe. With steel junction boxes, these two factors raised particular concern for hazard. More importantly, the breaker panel was overstuffed and obsolete.
Is a grounding knob and tube wiring safe?
Safe is a relative term. Knob and tube was used for decades, but it is subject to a variety of faults. Knob and tube wiring strings individual conductors on insulating knobs, usually in attics and then either uses knobs down through cavity walls or places both conductors in looms. Because the wires are substantially seperated, they emit a substantial magnetic field that may cause interference. That is an inconvenience, but not really a safety issue.Knob and tube wiring was phased out in part because it was more labor intensive to install, but also some hazards were introduced when thermal insulation was added. If a roof leaked and the insulation between wires became damp, that could generate leakage and eventually a fire. Also the wire was installed under tension, so stress on the structure from an earthquake and wind and structural failure could result in electrical damage. Anther hazard we think of with knob and tube is that in the era that it was installed, the preferred wire insulation was type "R" which was rubber and cotton. Rubber insulation oxidizes and becomes brittle with age. Rubber insulation is no longer considered appropriate for permanent installations because the useful life of the structure may be much longer than the useful life of the wire. This a strong reason for replacing knob and tube wiring during modern renovations, because the wire insulation may be failed, or near failure.Grounding helps to provide shock protection when electrical insulation fails and could energize a conductive case or other exposed metal. It does not solve any of the other failures above, but only provides a measure of safety if you are using something like a metal based lamp or metal cased appliance and it has a subsequent failure.
How can i tell which lead is hot? (old knob and tube wiring)?
1) The last half of your last statement scares the **** out of me. For you, your family and your house. 2) The only, ONLY place where the ground wire "IS" to be connected to any other wires is in the MAIN panel. Not even in the sub-panel. 3) If you ABSOLUTELY have to do this: go to Lowe's, Home Depot or any store like that near you and purchase a "Hot Stick" http://www.lowes.com/lowes/lkn?action=pr... This will detect voltage and doesn't need a neutral or a ground for SENSING voltage. Please read the directions. Good luck in all you do and may God bless.