It depends on what you have and what you use on those circuits, I'd say. What do you mean by 'lightly redone'?

If the old wiring is in good condition, and you mainly use it for lighting only, then I'd say it can wait...if you plug in every modern entertainment device and use them on the same circuit, then I might replace that circuit...it depends on how you use your devices.

If you have k&t, and it is in good shape, the only problem might be with insurance, but if you have insurance already, then it likely wasn't a factor in getting insured.

I guarantee it wasn't a factor when I got my insurance some twenty years ago in Ohio--in my basement, wiring was replaced and a circuit breaker system installed, but when I've had to replace a fixture or two, I found the old thickly insulated wires of k&t. It was actually in good shape so I left it in place--but then, I don't overload my circuits with power-hungry devices.

Aslong as you want to be takin a chance of a fire,big one..
That was one of the first things we did.

When I used to manage a number of older rental homes, I found the biggest risk with the wiring were the modifications over the years by diyers with barely a clue. Such things as extra circuits run with higher AMP fuses, lamp wire used to run circuits, no junction boxes and my favourite: all the finished basement circuits connected directly to the 60AMP main.

At the least, have your wiring and systems inspected by a licensed electrician.

"Aslong as you want to be takin a chance of a fire,big one..
That was one of the first things we did."

Very unlikely unless the wiring is overused or has been messed with (especially knob & tube).

Even old insulation that has become brittle works just fine as long as it is not disturbed.

The"lightly updated would worry me far more than old undisturbed wiring. Get an electrician in to inspect that pronto. If they did a bunch of join this to that and not in a junction box, I'd replace it immediately by a pro. If you're constantly popping breakers, plan to replace it within the year by a pro. If you have a fuse box instead of a breaker box, and you know you have knob and tube, I'd say to plan on replacing it within 2 years, and you have time to learn how to DIY a good portion of the job to save you some money. If it's just some "cleanup" type small wiring, I'd learn how to DIY that and work on it piecemeal with an experienced friend providing you some beer and pizza assistance.

If you have any other remodeling projects planned, the electrical goes to the top of the list now. Very few older homes can support the electrical demands of today's kitchens.

An inexpensive plug-in tester may reveal some problems immediately.

{{!gwi}}Source: toolsnworkwear.com

Thanks for the advice. By lightly redone, I mean 3 prong plugs were installed over the old 2 prong ones we used to have. Fortunately I'm never blowing breakers or anything along those lines. Heavy load stuff like entertainment systems have all new plugs and runs.

A tester will tell you if the old circuits are grounded. If the load isn't blowing circuits now, then it can wait if the wires looked good.

A concern might be grounded outlets in the kitchen or bath...otherwise from what you say it seems fine.

"By lightly redone, I mean 3 prong plugs were installed over the old 2 prong ones we used to have."

Did they simply replace the outlets or actually run a ground wire?

it is impossible to answer the question without more information.

the first safety hazard will come from wiring modifications - places where new wire was spliced into old, etc. if work to this point has been handled by professionals, this won't be an issue.

the second safety hazard will come from using three-prong devices in ungrounded outlets. the human safety risk can be eliminated by installing GFCI receptacles in these locations. the equipment protection aspect can largely be addressed through a whole-house surge protector.

if it were me, i would determine if the "new wiring" is, in fact new, and not joined with old K&T in haphazard circuits. exceptions would be something like keeping K&T from a light switch to a fixture. that is typically not a big deal. for my purposes, i would consider everything that is NOT K&T as "new."

But as I understand it with K&T, you must be careful not to blow insulation into the walls around it if it is active, right? Worth remembering. My insulation plans ground to a halt when y'all informed me of this.
Lynn

K&T depends on free air to dissipate any heat.

worthy
could you post a bigger pic of the tester?
I couldn't quite see the last one.

And what color is it? Is it orange?
lynn

Your wish is my command:

{{!gwi}}

Way to go, brickeyee--I thought it was hilarious!

That tester will not tell you what you need to know - is the insulation on your antique wiring cracking and in danger of shorting out and causing a fire. It will tell you if someone replaced a two prong (ungrounded) outlet with a 2P&G (two prong and grounded) outlet without actually grounding the outlet. That is dangerous only in that you may forget that it isn't truly grounded and be surprised when your computer turns into a toaster over night. Someone was right that adding one GFCI outlet on each circuit is an effective way of adding more circuit protection - required near water but useful elsewhere - but if you have a dirt crawl space it's not too hard to drive a few spikes into the ground and run ground wires up into the walls to your junction boxes. Or you can borrow a ground from a nearby circuit that is grounded. But get rid of the K & T wiring altogether - it's fine undisturbed but what happens when you go in the attic for some reason and disturb it? Or if you want to add insulation? Or critters come along and disturb it for you? Fix the wiring first. Now. Today.

"That tester will not tell you what you need to know - is the insulation on your antique wiring cracking and in danger of shorting out and causing a fire. "

K&T only depends on the insulation on the wires in the final connection to a JB or outlet.

Plain old air is the real insulation on most f a K&t system.

The insulation on the wires is for personnel protection to prevent contact with a conductor.

The hot and neutral are run many inches from each pother, and only come together at a JB or outlet to a device using power.

'Loom' was used to simply hold the wires together.
An open sort of 'netting.'

We bought a house built in 1957. Haha, it's younger than me. Nothing had been updated, but we thought it was cute. One night, while watching TV, half the rooms in the house went dark. We called in an electrician, who replaced all the wiring in the house. Including a new circuit box. Pretty expensive, around $10,000. But money well spent. The Town we live in required an inspection and issued us a "Certificate of Occupancy". We have done some room remodels since then, and moved an interior wall. But we are pleased our electric is modern. When we put in outdoor lighting and a swimming pool, there were no complications. You are playing with fire if there's 1922 wires anywhere.

"You are playing with fire if there's 1922 wires anywhere."

Old K&T that has not been messed with remains perfectly safe and acceptable under the NEC.

It is almost always the 'modern' attempts at alteration that are NOT done corretly. Ever seen an electrician solder anything in the past 80 years?.

The insurance companies like using it as a scapegoat.

According to the Ontario Electrical Safety Authority

"Myths

* Knob & Tube wiring is unsafe.

* All knob and tube wiring must be disconnected and replaced.

* The Ontario Electrical Safety Code no longer recognizes knob and tube wiring as an acceptable
wiring method.

Facts
* Knob & Tube wiring is safe, provided it is properly maintained by competent licensed people as outlined above.

* The Electrical Safety Authority as well as the Ontario Electrical Safety Code recognize and accept knob and tube wiring methods.

* The Ontario Electrical Safety Code 2002 edition contains rules that govern the installation of open type wiring methods (knob & tube). Rules 12-200 to 12-224 set out the minimum safety standards for the installation of open wiring, which may still be installed to this day."

Nevertheless, the practical reality is that, depending on your jurisdiction, many/most/all insurance companies will not cover you if you have k&t installed. Furthermore, if you check the restrictions on k&t in the linked bulletin, you will see limitations that make its continued use impractical, costly and inconvenient for most families.

An electrician soldered and taped two wires in my kitchen ceiling octagonal box in 1950. I called the electrical inspector and asked him what, if anything, I should do about it. After I told him the tape was not brittle, he told me to leave it alone. I could tell that he regarded soldering as some kind of golden age of electrical craftsmanship.

I soldered all the connections in one basement I renoed just to see if I could do it. (Kind of like Johnny Cash shooting a man in Reno just to watch him die.)

We have a 1920s home. Just a few years ago we had an electrician replace our fuse box with breakers and add a couple grounded outlets. And he looked over the old wiring where he could see it. He said no immediate problems but a good idea to replace eventually. I think very competent people built our house so we are pretty confident.

We couldn't run the toaster oven, coffee pot and microwave all at one time if the kitchen light is on, but hey who cares! Haven't had any problems since the breakers were installed.

We're saving up to redo the electrical once we finish painting and repairing, put on new roof and rebuild garage. Probably at same time as new garage with aptment above will be the time.

Kathy

"We couldn't run the toaster oven, coffee pot and microwave all at one time if the kitchen light is on, but hey who cares! Haven't had any problems since the breakers were installed. "

Now you know why the NEC has required two 20 amp small appliance branch for the kitchen counters.

It's not something you normally think about BUT if your home is in a flood did you know that the electrical panel IF submerged under water during the flood needs to be replaced as well as the wiring in the house?
I'm learning more than I ever cared to know about flooding issues.