Attic insulation on old wiring

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Posted by: from Regina
9/7/2012 at 1:07:58 PM

I bought an old house and thought that it had upgraded wiring, but the electrician discovered knob & tube wiring in the attic. I will not be able to afford to replace this, but would like the attic to be insulated, preferably with spray foam insulation.

Can this be applied on top of the knob & tube wiring, or would this cuase a hazard or other issues?

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Date/Time9/8/2012 at 2:43:23 PM

Hello, I am not sure how the house inspector missed Knob and Tube when you were under the impresion it had new wirring?........DO NOT SPRAY FOAM OVER KNOB AND TUBE WIRING.

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Date/Time9/10/2012 at 9:58:55 PM

I agree. The original design of K&T wiring was that it was in "free air" for the cooling effect.

I am sure there will be some people that will say it is OK and there are hundreds (if not thousands) of homes with K&T wire in insulated attics.

I would make the effort to replace the wiring before spending the money on insulating. If you must insulate, I would use blown or batts so they can be moved to access the wire when you can get an opportunity to rewire the place.



John Kuehnl-Cadwell

Master Electrician

Datawise Solutions Inc

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