Running Wires Under Floor Joists

Use electrical staples to secure.

Running wires under floor joists. The reason is wire breakage due to deflection of the joists a running board is allowed so that the nm cables are supported by a continous surface and the board helps limit deflection of the joists. After you ve run the wires through the clips you snap a plastic cover over the entire assembly. As jerry and john have said it is typical and acceptable to run the wiring under the joists in a crawl. Boring a hole through the rafters floor joists not only gives the wires a cleaner look but it makes them safer as well.

Keep the hole at least 2 in. If a lot of wires are already hanging from the bottom of the floor joists you can run the wires through raceways that fasten to the bottom of the joists. Drill holes with a diameter of no more than one third the depth of the joist staying 2 in. Away from the top and bottom.

Electrical staples are approximately 1 2. When a wire won t be visible it s fine to run it under the joists from the fixture to the side of the room where it will drop down to meet a wall switch. From the crawl space thread the wire from the outlet box down through the access hole and to the junction box or panel where the wire will eventually connect. The reason the smaller gauge wires cannot be stapled to the bottom of the joists has nothing to do with hanging clothes you could hang clothes on the wires if they are installed thru holes in the joists.

You simply mount a small plastic clip to every other joist. Depending on who and if this will be inspected in western pa you ll need to consult a local electrician or an inspector in your area to see what is the correct install method.