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not permitted on the bottom of joists. If notches are necessary elsewhere in the top of a joist, deeper joists must be used so that the net depth at the notch is equal to or greater than the joist depth required for the span and load conditions. The flanges of wood I-joists and truss chords and web members must not be notched or cut.
Drilled Holes in Joists Holes drilled in joists must not be larger than one-quarter the joist depth or closer than 50 mm (2 in.) to either edge (Figure 149). Holes in
engineered wood products must conform to the product manufacturers’ guidelines for size and location.
Notching and Drilling of Studs Load-bearing wall studs that have been notched or drilled to more than one-third of their depth must be reinforced (Figure 150), usually with 38 mm (2 in. nominal) lumber nailed to the side of the studs and extending
149 Maximum size of holes drilled in joists joist pipe maximum diameter of hole 1⁄4 of joist depth 50 mm (2 in.) minimum distance
150 Notching studs for plumbing
40 mm (19⁄16 in.) minimum
In partitions, notched studs need not be reinforced if remaining portion is at least 40 mm (19⁄16 in.).
⁄ stud depth minimum
23
In load-bearing walls, notched studs need not be reinforced if remaining portion is at least 2⁄3 the depth of the studs.