Using table a table b or both if required determine the hole shape size and select the tji joist and depth.
Cutting holes in floor joists for plumbing.
Away from the top and bottom.
Area provided there are no other holes in the joist or notches along its top or bottom.
Area in the middle of the 2 10 joist where the hole can go.
Check with the manufacturer as to the size of hole for the depth of joist rectangular holes are generally not permitted.
Where and how to drill joists for electrical cables or plumbing runs depends on what type of floor framing you have.
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.
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.
That gives you a 5 1 4 in.
Drill holes with a diameter of no more than one third the depth of the joist staying 2 in.
Minimum applies to all holes except knockouts closely grouped round holes are.
Minimum distance from table b 1 round holes may be cut anywhere in web outside of hatched zone if.
The diameter of holes shall not be greater than 1 3 the depth of the floor joists.
These types of joists are engineered and their structural performance relies upon their integrity not being compromised.
Sometimes joists are notched at the end where they bear on a wall or sill.
Never drill top to bottom through a joist.
Measurement shown is minimum distance from edge of hole to support.
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.
From the top and the bottom if it s a dimensional lumber joist.
These joists may need reinforcin g to reduce bounciness sagging or excessive deflection in the floor or ceiling.
Holes should only be drilled on the centre line of the joist.
They are located 3 away horizontally edge to edge from a larger hole.
Holes should have a diameter of no greater than 0 25 times the depth of the joist.
Rules for holes in joists.
Keep the hole at least 2 in.
This is where the compressive and tensile load distribution is neutralised.
For a 2 10 where actual depth is 9 25 inches the maximum allowable hole diameter would be just over three inches.
Permitted if the group perimeter meets requirements for round or square holes.
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.
Tradespeople often need to cut notches or holes in floor and ceiling joists to run pipes ductwork or wires.
You also have to leave at least 2 in.
Of solid wood between the top and bottom edges of the joist and the edges of any hole.
