• It is preferable for the notch depth to match the beam depth so that beam does not need to be notched as well.
• Bearing width is controlled by perpendicular-to-grain bearing. Reasonable minimum bearing width of 1″.
• NDS allows notching glulams with limitations outlined in section 5.4.5 while considering requirements for shear capacity in 2018 NDS 3.4.3.2 (or 2024 NDS 3.4.3.1) and 5.3.10. Bending capacity at notches should consider the net section per NDS 3.1.2. Refer to AITC Technical Note 19 and APA S560 for more guidance.
• Notches in wood elements including glulam may be strengthened by fully-threaded screws reinforcing the potential crack location. One design method of screw reinforcement is provided in MTC Solutions’ Timber Reinforcement Guide.
• Bearing on a notched glulam introduces tension perpendicular to grain. Review NDS sections 3.8.2, 11.1.3, and Commentary section C12.5. For perpendicular to grain connections, the member is required to be checked for shear in accordance with 3.4.3.3 and 5.3.10 using the reduced depth.
• The mid-span notches in the girders as shown are outside the scope of notches permitted in the NDS and should only be used after careful consideration and justification through alternative means.
• Deck not shown for clarity. Beam may require bracing for lateral-torsional buckling.

Other Applications:

• Table 9: Mass Timber Beam Support at Mass Timber Column
• Table 10: Mass Timber Beam Support at Mass Timber Wall Panel