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	Subject - Knob&Tube panel upgrade MONOLITH In the other thread about home inspection liability, I mentioned the scenario about several disconnects all tapped together and 'octopussed' on the basement wall. I am sure you guys have seen this before, an old knob and tube house with one 100Amp fusible disconnect, and from the load side of this disconnect is tapped multiple smaller disconnects from various circuits added throughout the years. There must be at least seven of them, for all sorts of things from an electric range, to furnaces, The owner wants me to make several code corrections and circuit additions to the home, including a new dishwasher circuit, and a new kitchen small appliance (counter outlets) circuit. I am going to tell the homeowner that unless she wants to upgrade to a circuit breaker panel, and get rid of all the tapped disconnects, I will not be able to 'tap' additional disconnects and add to this nightmare in the basement. I'm just wondering if you agree with me. Would you insist on the panel change before doing additional work, or would you be willing to make additional taps and disconnects in the basement for these additional circuits? Thanks. kiwisholland Definately new service, or I wouldn't do anything else to her house. Murphys law. That old wiring is just waitng for the right time to start tp crumble. blackrd I wouldnt touch that job without replacing the panel first. I would insist on it. If you lose the other work because of it, you better off. Let some unskilled bastard risk his livelhood doing a half-*****. At least you wont lay awake at night worrying when that job you just did is going to grenade on you. MONOLITH Yeah. That is the position I took. The proposal is in her hands this afternoon. We'll see what she says tomorrow. Thanks. Romex Racer I tell people that I also do home electrical inspections for realators and that if she sold the house, this electrical wiring would have to be replaced anyway before a sale. John A. Peters And the house would look a lot safer to a potinetal new owner, with a new panel. blackrd and you would feel beter knowing you did a good job and are now $800-$2400 richer MONOLITH Looks like I may be closing the deal first thing in the morning, including the panel change. MONOLITH Talked to her this morning. I'm doing all the work, including the panel upgrade. jdcastle4ttu MONOLITH, In my area, I don't think anyone had electricty before the end of the knob-and-tube era, and if they did, it must have burned down years ago because I have never seen it in use. That said, I was wondering what you would do with the origional wire. Tie it back directly into the new panel, replace it completly, splice it together in a secondary box, etc... Just curious. MONOLITH I think in this particular case, I'm going to end up with a couple of junction boxes where the old disconnects are, and run Romex from the new panel to these Jboxes and splice on. blackrd I think it would be better to remove/replace it, preferably where it is concealed up in the joists and wall cavitys. Not to hide the k&t, just to clean up the clutter around the panel. But this may not be possible for several reasons. I wouldnt fault a guy for splicing near the panel w/jboxes, Ive seen it(and done it). kiwisholland Around here, when you upgrade a service, you have to terminate ALL K&T as soon as it emerges from the walls in a JB and splice to romex back to the new panel. Is K&T slowly becoming the next asbestos/mold? Inspectors? Insurance guys? Alfred I'd make a whole month of it. Get ride of all the knob and tube. It's seen it's better day. I remember working on an old house like that one time, had to use high speed drill bits on every thing. Glad when the job was do. Just a bit of advice. Thanks Alfred Johnson MONOLITH I hadn't really thought about trying to convince the owner she had to have the entire home rewired to the tune of $20,000. It wasn't really something I had considered getting that involved in. Anyone else with any personal experience in that sort of thing? John A. Peters [b]Fuses and knob & tube wiring[\b] are discriminated against by the insurance companies. The presence of fuses usually means that the rest of the building wiring has not been updated. Fire Insurance - Some fire insurance companies offer to reduced rates. You may be able to reduce your annual rates by 50%, if you remove all the wiring that is older than twenty years old. Knob & tube - This wiring method is commonly found in old houses.wiring is nearing the end of it's life expectancy, according to the chief building inspector in San Francisco. I attended a brown-bag-lunch seminar at the building department where the chief said that what he did in his home, was to have all the plug outlets rewired with modern wiring. He let the lighting circuits remain on the knob & tube wiring since lighting is not a heavy load. Heaters and motors use the most power. Knob & Tube defined - The "knob" is a two part porcelain insulator with a nail in the center. The nail secures the knob and clamps the wire firmly, suspending the RH wire at least one inch away from wood and other combustible surfaces. A "tube" is a white porcelain tube about 5/8 inched in diameter. It is used to line a hole in wood where the required one inch of spacing can not be maintained where the passes through wood. "Loom" is a flexible tube made of semi-flexible cloth or fiber. Loom is used where there is a need for a longer run of wire through a hollow wall or through several wood members. Temperature ratings - RH is an older wire type commonly used with know & tube wiring. RH stands for Rubber Heat. RH wires are copper wires that were wrapped in cloth and then impregnated with rubber. RH insulation is not able to withstand a high temperature for very long. It is not any where nearly the equal to the temperature rating of modern wiring The insulation falls off in a fire. After type RH came TW which was rated for 40 degrees centigrade. This insulation is commonly found in raceways and conduits in older houses and buildings. Currently the standard wire is THHN insulation which is rated for up to 90 degrees centigrade. It does not cause much trouble. Fixture temperatures - Some modern fixtures require building wire suitable for 90 degrees centigrade. You can check this by reading instructions. Typically a fixture that is a pendant or chain hung fixture does not have this requirement. With the lamp holder hanging down below the ceiling the heat is not transferred to thee building wiring. Other fixtures look like an inverted cake pan or bowl, and these fixtures trap the heat against the ceiling. These fixtures usually require 90 degree building wire. Some of these have a blanket of insulation between the fixture pan and the ceiling to keep the heat away from the building wires. Be sure to read the label and or instructions which will have a maximum wattage for the lamps. Exceeding this wattage will make the lamp holder and wired degrade and eventually disintegrate. This means that in an old house you need to have your wires upgraded or at least properly converted at the fixture.