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joe15947
k n t and insulation

I would like to insulate my cold 1949 bungalow, but I heard the foam and fiberglass insulation would trap to much heat and possibly be a fire hazard for the old knob & tube electrical. Any suggestions?

jkirk
Re: k n t and insulation

ive never heard of this. it wont keep in so much heat as to create a fire hazard unless you have knob and tube or old faulty wiring

tomn10
Re: k n t and insulation
joe15947 wrote:

I would like to insulate my cold 1949 bungalow, but I heard the foam and fiberglass insulation would trap to much heat and possibly be a fire hazard for the old knob & tube electrical. Any suggestions?

I would suggest to re-wire and get rid of the KnT. KnT is a fire hazard. Then you can insulate anyway you want.

Re: k n t and insulation

Knob & Tube wiring is the oldest wiring method in the US.

Wiring on the cleats is automatically spaced 3 1/2" apart except when run into a box. So it's insulation does not come into play.

If the feed to a box has faulty insulation and becomes overheated it could short the wires together and blow a fuse, breaker, or worse, start a fire.

Also, K&T wiring doesn't have a ground wire. If possible, it should be replaced.

thesemi-retiredelectrician.com

ZZZ
Re: k n t and insulation

The reasoning is that the wire insulation was not very heat resistant, and depended on free air for cooling. Since insulation cover is a code violation, NEC 394.12 (5), it can lead to an expensive correction when a home inspection catches it. I have seen the situation interfere the sale of more than one home. It is much easier to replace the wire before the insulation is added.

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