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Electrical additions

Dean Manoogian | Posted in Building Code Questions on

Portland, Maine. In remodeling I have gutted the interior of a 1950 cape cod.The electrical has been removed and new going in. All boxes will be in interior walls only and there will be no ceiling light fixtures. Two questions. Can I run wires in floor beam spaces (just above 1st floor cieling drywall) both perpendicular and horizontal to the bays and meet code without drilling holes in the floor beams? I have to add CO and fire alarms. Can these be put at the top edge of the wall or do they have to be on the ceiling?

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  1. GBA Editor
    Martin Holladay | | #1

    I'm not an electrician, but as far as I know -- yes to installing the CO and smoke alarms on the wall (although check distance requirements in terms of the distance of the detectors from the ceiling, because there is usually a dead pocket of air right in the corner), and no to installing Romex directly under the drywall. Get out the Milwaukee drill with a right-angle attachment.

  2. Nathan Spriegel | | #2

    There are NFPA requirements to keep detectors out of the "dead air" spaces Martin mentioned. The installation instructions should list them. Is this in an area requiring permits? If so remember you need an outlet along every 12 feet of wall per the NEC, unless you are placing them near the wall in the floor (with certain exceptions and assuming your state/county has adopted the NEC without modifications). When you say "just above", do you mean laying ON the drywall or secured to the joist? As long as you maintain a 1.25" clearance from the drywall to your wiring I believe you will be in compliance with the NEC. If you must drill please follow code and manufacturer (if a manufactured joist) guidelines to where and how much you can remove.

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