Preparing attic wiring for foam insulation.

Old 09-21-14, 10:09 AM
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Preparing attic wiring for foam insulation.

I am considering insulation foam for an attic.

Pictures of the attic crawl space wiring.

I have an attic with:

1) 2 conductor , no ground, wire draped over rafters. The wire is not tacked down, it runs over the top of the rafters.

2) Some of the wire is newer wire with a ground. But is still just draped over the rafters.

3) there is a system of smoke detectors with low voltage wire also draped over the rafters.

4) There is no energized knob and tube.

In many places wire collects at the bottom over the attic ceiling. If it were foamed the wire would be completely covered by foam.

Should I replace all the 2 conductor wire with modern grounded wire?

Should I support the existing wires with wooden bridging?

Any other prep for the foam you recommend?
Old 09-21-14, 02:19 PM
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I see a junction box and probably more. Make sure they are not covered, must remain "easily accessible" by code and of course if you have to get to them in the future. Are you just putting foam between the ceiling rafters or above that which in turn would be covering over the wires crossing the raters. Wires going cross rafters should be in a channel so it is protected.
Old 09-21-14, 10:59 PM
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I would replace all the older and non grounded wiring while you have a chance.

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