Insulation, Radiant and Vapor Barriers - Fiberglass R30 over knob & tube? Ok?

I have an older home (built in the 40's), single story with a small attic space. The attic is uninsulated. About 1/4 of the space is knob/tube wired. Is it safe to roll insulation out over the knob/tube? Also, would it do any good to insulate the rafters? If ok, any recommended strategies?

Thanks.

I have an older home (built in the 40's), single story with a small attic space. The attic is uninsulated. About 1/4 of the space is knob/tube wired. Is it safe to roll insulation out over the knob/tube? Also, would it do any good to insulate the rafters? If ok, any recommended strategies?

Thanks.

Knob and tube wiring is highly dangerous and can be a fire hazard.

Get an electrician in today to check ALL your wiring!! Have your wiring checked and redone throughout your house.

Bring your wiring up to code and then insulate.

We're in the process of a remodel so it will be switched out in about 6 months. I'll insulate in the spaces where theres no knob/tube for now.

Thanks.

I think the statement below may be a little alarmist. I'm not an electrician, but the opinions of any that I have consulted, indicate that knob and tube wiring is not necessarily hazardous and does not necessarily need to be replaced. I think it is wise to consult an electrician and have the wiring tested, and I certainly wouldn't insulate over it, but I don't think there is any need for those with knob and tube wiring to panic. Poorly done modern wiring can also be a fire hazard.


Knob and tube wiring is highly dangerous and can be a fire hazard.

Get an electrician in today to check ALL your wiring!! Have your wiring checked and redone throughout your house.

Bring your wiring up to code and then insulate.

Good that you are getting the knob and tube replaced.

I have seen knob and tube blow a house sale more than once.

To make the sale work, the price ends up being reduced in order to close or you end up having it corrected at the wrong time for too high a price because of the timing.

In the case of a sale, it is not a question of being a potential hazard, but the fear the buyer has when there are other houses out there without knob and tube.

Dick

Thanks for the input, after posting I did some research and knob/tube is safe and efficient if well maintained. Ours has been inspected and is in good condition. As a precaution I only insulated cavities where no wiring was placed.

The home sale situation with knob and tube is not a code issue. It is a perception issue. Between an offer and a closing, comfort and satisfaction rather than codes is the critical $$$ issue.

A home inspector should report the existance of the issue. After the inspection, the buyer usually has an option for correction, adjustment in price or could possibly walk away without losing the deposit.

Dick

The home sale situation with knob and tube is not a code issue. It is a perception issue. Between an offer and a closing, comfort and satisfaction rather than codes is the critical $$$ issue.

A home inspector should report the existance of the issue. After the inspection, the buyer usually has an option for correction, adjustment in price or could possibly walk away without losing the deposit.

Dick

You are correct, but I believe it is an electrical code violation to cover knob and tube wiring.

Buzzard - You are correct about covering it.

I was speaking from a selling situation. It is generally OK to have it. A home inspection would probably not discover it if it was covered, since the inspection is limited to readily visual items. The only way a home inspector would notice the knob and tube would be if he saw clues in the service box, at an outlet or switch or if he happened to move enough insulation.

The liability limitations of walking and crawling around in an attic covered with insulation make it hard to happen on.

Unfortunately, home owners frown when an inspector hired by a POSSIBLE purchaser falls through HIS ceiling when a suspected joist is not there. It is always fun working out the liability. Falling through a ceiling is not worth the $250 to $350 inspection fee. Falling off a roof is a bigger liability question.

Dick

It is a code violation to cover K&T wiring with insulation. K&T wiring in good condition presents no safety hazzard but I would certainly get it out of there during any sort of renovation. Any three prong outlets connected to that K&T wiring? That would also be a code violation, and using those little grey *******s doesn't solve the problem either. All that does is create a saftey hazzard.