Cutting Holes In Floor Joists For Plumbing

Holes should be no closer together than 3 times the.

Cutting holes in floor joists for plumbing. Holes should have a diameter of no greater than 0 25 times the depth of the joist. This is where the compressive and tensile load distribution is neutralised. Using table a table b or both if required determine the hole shape size and select the tji joist and depth. 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.

Scan horizontally until you intersect the cor rect hole size column. Running wires or water supply lines through floor joists is a bit tricky but there is a way to cut the necessary openings through the joists safely. That gives you a 5 1 4 in. You also have to leave at least 2 in.

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. Sometimes joists are notched at the end where they bear on a wall or sill. Permitted if the group perimeter meets requirements for round or square holes. Tradespeople often need to cut notches or holes in floor and ceiling joists to run pipes ductwork or wires.

Drill holes with a diameter of no more than one third the depth of the joist staying 2 in. Rules for holes in joists. Measurement shown is minimum distance from edge of hole to support. Area provided there are no other holes in the joist or notches along its top or bottom.

Minimum distance from table b 1 round holes may be cut anywhere in web outside of hatched zone if. Away from the top and bottom. Never drill top to bottom through a joist. The diameter of holes shall not be greater than 1 3 the depth of the floor joists.

Minimum applies to all holes except knockouts closely grouped round holes are. Keep the hole at least 2 in. Check with the manufacturer as to the size of hole for the depth of joist rectangular holes are generally not permitted. These types of joists are engineered and their structural performance relies upon their integrity not being compromised.

Holes cannot be closer than 2 to the bottom or top of a joist or to another hole or notch in the joist drilling floor joists. Where and how to drill joists for electrical cables or plumbing runs depends on what type of floor framing you have. From the top and the bottom if it s a dimensional lumber joist. Of solid wood between the top and bottom edges of the joist and the edges of any hole.

Area in the middle of the 2 10 joist where the hole can go. Where the property contains metal web joists as shown in fig 2 no notching drilling or cutting in either the timber flanges or the steel webs is permitted. For a 2 10 where actual depth is 9 25 inches the maximum allowable hole diameter would be just over three inches.