Drilling Holes In Floor Joists For Electrical Wiring

I need to run about 8 x 14 2 wires 12 wire water heater 10 dryer wire and 2 x 12x2 wires through a set of 10 floor joists 2x10.

Drilling holes in floor joists for electrical wiring. I m in bc canada and need to figure out how many holes i need to bore in the dimensional floor joist lumber and the number of wires i can run in each hole as a run across the room to a main panel. For a 2 10 where actual depth is 9 25 inches the maximum allowable hole diameter would be just over three inches. From the top and the bottom if it s a dimensional lumber joist. As part of any new installation work or a re wire a cable trunking or cable tray sometimes has to pass through an element of building construction such as a floor wall or beam necessitating the formation of a notch or opening in the element.

Sometimes joists are notched at the end where they bear on a wall or sill. Holes cannot be closer than 2 to. Where and how to drill joists for electrical cables or plumbing runs depends on what type of floor framing you have. Cutting notches and drilling holes in joists.

If you have manufactured floor joists you will want to consult the particular manufacturer s literature. If the cut outs are too large or in the wrong location the joist can be weakened and unable to support the load it was designed for. The hole cannot be larger than one third the depth of the joist so the maximum hole size for a 2 12 joist actual size 1 1 2 x 11 1. The diameter of holes shall not be greater than 1 3 the depth of the floor joists.

In a perfect world floor joists are left whole to provide the greatest support. Tradespeople often need to cut notches or holes in floor and ceiling joists to run pipes ductwork or wires.