Is it OK to drill through floor joists?

You can drill the holes anywhere along the length of the joist (first photo). If you have manufactured I-joists, you can drill holes up to 1-1/2 in. diameter almost anywhere in the web area (the area between the flanges).

Can you notch a floor joist?





You can cut a notch at the end of the joist to 1/4 of the joist’s depth (maximum). Along the outer third of a joist, you can cut a notch a maximum of 1/6 the joist depth and 1/3 the joist length without compromising its strength.

Can you drill a 4 hole in a floor joist?

Although notches aren’t allowed in the center third of a joist’s length, you can drill holes anywhere along the length of the floor joist in that 5 1⁄4-in. area provided there are no other holes in the joist or notches along its top or bottom. If there are other holes or notches, keep at least 2 in.

How close to the end of a joist Can I drill a hole?

Don’t make any holes with a diameter greater than 1/3 the depth of a joist. ‘ No holes closer than 2 inches to the top or bottom edge. No holes closer than 2 inches to any other hole or notch.

How big a hole can you drill in a floor joist?

You can put holes in floor joists anywhere along the length of the joist, but you can’t put them any closer than 2″ from the top or bottom edge of a joist. The maximum size of a hole is 1/3 the depth of the floor joist.

How much of a joist can be notched?





Should be no deeper than 0.125 times the depth of the joists. Should be no closer to the support than 0.07 times the span and no further away than 0.25 times the span.

Where do you notch a floor joist?

Rules for Notches in Joists

  • Notches should only be made in the top edge of the joist.
  • Notches should be no deeper than 0.125 times the depth of the joist.
  • Notches should be no closer to the structure supporting them than 0.07 times the span of the joist.
  • The notches should be no further away than 0.25 (¼) times the span.


What are the codes for drilling or notching joists?

Holes bored in joists shall not be within 2 inches (51 mm) of the top or bottom of the joist, and the diameter of any such hole shall not exceed one-third the depth of the joist. Notches in the top or bottom of joists shall not exceed one-sixth the depth and shall not be located in the middle third of the span. R502.

How do you reinforce a notched floor joist?



You can reinforce a notched joist that has not cracked by cutting two pieces of 3/4-inch plywood as wide as the joist depth and as long as the plywood sheet. Screwing a piece to the joist on each side offers moderate reinforcement. Stronger reinforcement is in order if the joist is sagging or has cracked.

Can I drill a 3 hole in a 2×10 floor joist?

Simply following building code, you’ll only be allowed to bore a 3-5/64″ hole through a 2×10 joist. A 2×10 is actually only 9-1/4″ deep, and building codes set the maximum hole size to 1/3 the depth of the member (9-1/4″ / 3 = 3.08333″).

Does screwing into a joist weaken it?

When weight is applied to a joist, the top edge goes into compression while the bottom edge goes into tension. Improperly sized or placed holes and notches weaken the joist, make it bouncy and saggy, and provide an easy place for it to crack and fail.

Can you run a drain pipe through a floor joist?



Running drainpipe through joists calls for meticulous work. The holes must follow a straight line across the floor and must ascend or descend so the pipe will be sloped 1/4 inch per foot. (If joists are 16 inches on center and pipes run across them at a right angle, holes should differ in height by about 3/8 inch.)

How do drain pipes run through joists?

Quote from the video:
Quote from Youtube video: The joist bays. And you're going to need a coupling. And if you're going to do this you're going to go farther you're going to need more couplings to get the job done and even for a job like.

Can you run PEX through floor joists?

The Advantages of PEX



PEX, a flexible tubing that comes in long rolls, offers several advantages over traditional piping. First, you can usually make long continuous runs, eliminating most elbows and joints. You can snake long runs through joists and studs.

Can you put 40mm waste pipe through joists?

Running waste pipes through joists should be avoided where possible, as any drilling of joists (also known as notching joists) may weaken them and compromise the structural integrity. When you do need to notch a joist, you should use the following rules: Only insert a notch into the top edge of the joist.