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My elderly parents live in a 46-year-old house in southern Illinois. I am very concerned about the condition of the wiring in the house. When my husband replaced a kitchen ceiling light a short time ago, he said the insulation around the wiring was crumbling and brittle.
Do I have reason for concern?
I live a thousand miles from them. What can I do from long distance to seek help with this problem?
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Replies
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Have you thought of having an electrician take a look and maybe give you an estimate to rewire the home as he see's necessary?...
That's what I would do along with make sure a couple of smoke alarms are in place and functioning....
near the stream,
aj
*The old knob and tube wiring is basically stable until someone touches it. The wires are probably fine inisde the walls, because no one is manhandling it. They are generally 10 guage, thicker than what is usually placed in new homes today, and generally separated by about 16" with each line (hot and neutral) on separate joists or studs, so they will not overheat.The problem is when one has to deal with them, by changing out lighting fixtures or working in a box, the old cloth insulation just crumbles.Suggestions:'b ' Leave it AloneI have re-habbed a number of houses, and when I come upon it, I just leave it alone. It is perfectly good wiring, unless you start messing with.'b ' If You Must Mess With It, Be CarefullThe stuff does not like linesman's pliers, and one simply can not use the same techniques when working with it. I always shut off the power, use my hands, not pliers, and often find myself using heatshrink insulation or lotsa tape for damaged sections. Use wire nuts, cinch them down well, and tape over the wire nut. Rather than cram an old section into a new splice, I also use pig tails to make connections to new splices, where I can break out the pliers without fear.'b ' There is No Ground, So Consider Using Cold Water Pipes.Because there is no ground on old knob and tube, I use cold water pipes and a manual ground pipe at the box and Romex into the dwelling to create one for future use'b ' Avoid the Tendancy to Replace It, Unless You Can Do So in Distinct SectionsI was doing a room last month and ran accross a room full of the stuff. While the temptation was to replace it all since I had all the walls and celings open, one problem was "Where in the Heck to Stop", because the lines continued into the next room. I would have to make a splice and place the splice in a box which is illegal here in SoCal. You can only replace sections that are distinct, and you must go all the way to the box.Bottom line? Unless you want to re-wire the whole house, I would leave well enough alone. I don't mean offense, but your husband was probably not experienced enough to be working on the stuff. But now that you have my thoughts, maybe he could give it a try.
*MJ,Jack is right on the money.Is the wiring knob and tube? Two separate wires that run through insulators? Or perhaps old style romex? Not that it makes a difference because brittle insulation on any wiring is a cause for concern. Are your folks ok dealing with an electrician, or would you feel better handling that job for them. Over the phone dealings can many times be bogus for both the customer and the contractor. Try to find someone you can trust there to make contact with a reputable tradesman and submit maybe to them some references of yourself. But if you can make it, take care of it yourself.Best of luck, wish I was from S. Illinois.And don't forget the 110 v./ battery backup smoke alarms.
*Hi Maryjo - The guys forgot to mention that the usual reason insulation is dry and crumbling above light fixtures is because of its exposure to heat from the bulbs all those years. There are methods for dealing with the few inches of bad insulation at fixtures.Smoke detectors in the house are always a good idea, as was mentioned.Lee
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Thanks! mj
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Knob and tube in 1954?
Didn't think they still used it then.
MD
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great information--thanks! I don't know if it's knob and tubing or old romex--I wasn't sure anyone would see my message or care, so I didn't go into much detail about my concerns other than the ceiling fixture. I think the house is under serviced. Sometimes when I've been there and my mother is baking, washing clothes, drying clothes, running the air conditioning (central system), the lights flicker in the house--to me that spells trouble, and I keep thinking there could be a fire inside the walls. What do you think?
mj
*yes, I suspect it's old romex, not knob and tubing but I know it's not metal conduit, and that's what scare me.mj
*great information--thanks! I don't know if it's knob and tubing or old romex--I wasn't sure anyone would see my message or care, so I didn't go into much detail about my concerns other than the ceiling fixture. I think the house is under serviced. Sometimes when I've been there and my mother is baking, washing clothes, drying clothes, running the air conditioning (central system), the lights flicker in the house--to me that spells trouble, and I keep thinking there could be a fire inside the walls. What do you think?mj
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Ed Lee beat me to it. I've seen this a lot- the insulation on the fixture wire doesn't hold up. Yes it could be serious, but easily fixed.
*What I want to know is:Why did the guy who installed this bother hooking up the white wire ?
*Yes, you ought to be concerned, and it's terrific that you are asking.Be careful hiring an electrician: I bet you'll get widely varying quotes, some insisting a complete rewire is the only sane solution, others (competent or not) bidding much smaller jobs. Then there are the vermin who deliberately prey on older folks. If he doesn't do a real inspection of the premises first, give him the boot. Is there anyone out there who's knowledgeable and trustworthy to sit in on the bids? At least, someone scary-looking?I would bet the insulation is cloth in BX armored cable -- your experience sounds exactly like mine in a 1940 house. Nothing inherently wrong with it if not damaged.Wasn't Romex a 60's thing, the age of plastics (see The Graduate)? Crumbling at the touch sounds like overlamping, putting a big bulb in there and cooking the insulation. If so, the damage is very local. Pretty irritating when I could not get enough good cable to rewire, and had to fish a new run. Plug outlets may also show similar deterioration -- our neighbor plugged in a laptop and got a small fire.Cold water pipe is not good, nor legal, for grounding. It's too likely there is corrosion or a dielectric union or whatever somewhere. Use a GFCI or, best for appliances like the fridge, new cable instead (GFCI's can "nuisance trip"). Running new Romex may not be too hard for many locations ... I've replaced circuits as it became convenient, focusing on high-current ones.Don't forget to check for aluminum branch circuits that may have been installed in remodels, they need special care to prevent fire.Smoke detectors, great! Few people, esp. the vulnerable elderly, have properly working ones, and I like them in the bedrooms too. Consider CO detectors too if they have combustion appliances.
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It most likely is the bx cable, and all of the posts are right on the money, ie overlamping the fixture, smoke detectors(batteries 2x a year), loose connections (flickering lights)and the like. However it is possible that itcould be knob and tube, check the attic to confirm. If it is bx (looks like romex but with a fabric wrapper instead of plastic)it is fairly easy to solve problems, but I recommend a competent electrician. If it is knob and tube, check to see that no lines are covered with insulation (retrofit) as these lines must be allowed to disapate heat without interference from the insulation, if covered they are a severe fire hazard. Wish you luck.
*It most likly is the bx cable, and all of the posts are right on the money, ie overlamping the fixture, smoke detectors(batteries 2x a year), loose connections (flickering lights)and the like. However it is possible that it is knob and tube, check the attic to confirm. If it is bx (looks like romex but with a fabric wrapper instead of plastic)it is fairly easy to solve problems, but I reccommend a competent electrician. If it is knob and tube, check to see that no lines are covered with insulation (retrofit) as these lines must be allowed to disapate heat without interference from the insulation, if covered they are a severe fire hazard. Wish you luck.
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B Rozett,
I believe you may have incorrectly described BX cable. It's a a metal shielded cable, as andrew d notes above, with the metal sheathing in spiraled strips for flexibility.
*The wiring described can't be knob-and-tube - it had gone out of use in most areas by the 1920's. Unless it runs in flexible metal cable (like M/C cable) it is probably what most electricans around here refer to as 'braid' - ie braided cloth cover over fairly heavily-jacketed rubber (or plastic) insulation. Frequently had a green-jacketed ground wire of smaller gauge than hot and neutral.In our 1932 Dutch Colonial we've had the same problem with wiring at ceiling fixtures. The wire type is braided cloth over rubber (or plastic) insulation within flexible metal cable.If it's the same wire type, remember one thing the cloth can be a mess but it's the rubber (or plastic) that does the insulating, so don't panic, a pro needs to look closely at it to see how bad it really is.I've fixed all of these conditions easily and inexpensively in our house by purchasing heat-shrink tubing (Radio Shack), slipping it over the questionable exposed ends and shrinking it with a hair dryer. In a few worse cases, I've stripped the old plastic, slipped modern Romex insulation (or better yet, THHN from individual cables) over the stripped area and then the heat-shrink tubing.Professional electricians in our area do the same.Good luck! - Jeff Clarke
*Another good product for insulating old wires was mentioned in the "Old Electrical Wiring" book recently reviewed in FHB which is a silicone impregnated fiberglass woven tubing which can give higher temperature rating to even new wires which is needed for installation above some fixtures. The stuff is available in electronics supply stores and is not expensive. You might ask your electrician about using it as extra protection especially if the fixtures installed require 90 degree capability wire insulation. Good luck. Rich.
*Effective but not necessarily beautiful, one could also install a splice box at some easy fishing distance from the fixture box, running 90°C wire to the fixture and dicarding the damaged wire. I don't like the idea of trying to salvage roasted wire, maybe I'm too conservative. I think you have to pretty much assume people will overlamp the fixture in the future, too. My theory is that 100-watt bulbs should be banned until they cool them down. :) The flush ceiling fixture is one area in which CFL & circular fluorescent bulbs esp. excel.The splice box has to be left accessible for "maintenance," not buried in the wall or ceiling. Note that it doesn't neccessarily have to be in the same room -- it could be on the other side of a wall stud bay, for example.A whole new run to the switchbox is nice if possible, and it's a great mental exercise to achieve one with a minimum of damage! (Once you get past the swearing, that is.)
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Every time I read the new messages, I think of something else. I lived in that house from 1954-1970, and the ceiling fixture was circular flourescent tubing (very '50s).
*I stand (actually sitting at computer screen) corrected. What was I thinking? Oh well, another typical day. Thanks for pointing it out, more proof that it's not only what you say, but how you say it.
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My elderly parents live in a 46-year-old house in southern Illinois. I am very concerned about the condition of the wiring in the house. When my husband replaced a kitchen ceiling light a short time ago, he said the insulation around the wiring was crumbling and brittle.
Do I have reason for concern?
I live a thousand miles from them. What can I do from long distance to seek help with this problem?