I spent all of last week at the Utah chapter annual business meeting, and had a great oppritunity to discuss things with different vendors that helped sponsor it for us. Among those was Boise Cascade, who gave me a great booklet on their glulam beams, including some information about drilling them. I hope this can be of some use to somebody.
Could you please post the same info for a regular 2x dimension lumber joist?
From the 2000 International Residential Code, Section R502.8.1
Sawn Lumber. Notches in soliod lumber joists, rafters and beams shall not exceed one-sixth if the depth of the member, shall not be longer than one-third of the depth of the member and shall not be located in the middle one-third of the span. Notches at the ends of the member shall not exceed one-fourth the depth of the member. The tension side of members 4 inches or greater in nominal thickness shall not be notched except at the ends of the members. The diameter of holes bored or cut into members shall not exceed one-third the depth of the member. Holes shall not be closer than 2 inches to the top or bottom of the member, or to any other hole located in the member. Where the member is also notched, the hole shall not be closer than 2 inches to the notch.