- Should only be made in the top edge of the joist
- 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.
Maximum notch depth
|Joist depth||Notch depth|
- Should only be drilled on the centre line of the joist.
- Should have a diameter no greater than 0.25 times the depth of the joist.
- Should be no closer together than 3 times the larger diameter.
- Should be no closer to the support than 0.25 times the span and no further away than 0.4 times the span.
- If the above requirements cannot be met within the limitation shown, then increase the joist depth by the depth of notches or diameter of holes.
Last updated: Wednesday, 5 October, 2022.