Question: What are the limitations for notches in floor joists? Bored holes?
Answer:
Notches on the top or bottom edges of solid lumber floor joists cannot exceed one-sixth of the total depth of the member, are completely prohibited in the middle third of the span, and cannot exceed one-fourth of the depth when located at the ends. For bored holes, the diameter is limited to a maximum of one-third of the joist depth, and they must be positioned at least 2 inches away from both the top and bottom edges as well as from any adjacent holes or notches.