cable run across insulated wall
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cable run across insulated wall
Hey folks,
When running cable horizontally through studs of an exterior wall that has insulation with a vapor barrier (or when replacing insulation in a wall with an existing cable), should the cable be kept between the barrier and the inside wall or the unfaced side of the insulation and the exterior wall? I’ve seen it both ways and was wondering if there was a code or “unwritten rule” about it. (One time I saw where the installer made a slit in the insulation’s unfaced side so it would “slip over” the cable and keep the insulation flush to the exterior wall which, I would think, could lead to over heating issues.) Would it matter if the cable was NM, AC, or loose wire in EMT raceway?
Thanks in advance.
When running cable horizontally through studs of an exterior wall that has insulation with a vapor barrier (or when replacing insulation in a wall with an existing cable), should the cable be kept between the barrier and the inside wall or the unfaced side of the insulation and the exterior wall? I’ve seen it both ways and was wondering if there was a code or “unwritten rule” about it. (One time I saw where the installer made a slit in the insulation’s unfaced side so it would “slip over” the cable and keep the insulation flush to the exterior wall which, I would think, could lead to over heating issues.) Would it matter if the cable was NM, AC, or loose wire in EMT raceway?
Thanks in advance.
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You can make a slit in the unfaces side of the insulation if you want, or you can just let it bunch around the cable. Do not run the cable between the vapor barrier and the inside wall.