National Electrical Installation Standards

Standards as High as Your Own

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Monday, November 27, 2017

Question:

Can nm3-B be out of conduit inside an attic crawl space?

Rich Bolles

A

Answer:

Hey Rich thanks for your question. Nonmettalic-sheathed cable can be installed in attics and if exposed must follow 334.15. If in an accessible attic 334.23 references 320.23 which requires additional protection where run across the top of floor joists or within 7 ft of the floor and installed across the face of framing members. Cable installations must comply with 300.4 and if subject to physical damage additional protection is necessary such as by the use of conduit, guard strips, or other approved means.

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