Can I drill 3-1/2" holes through five joists?
This bracket provides a building code approved solution for holes up to 6&quot; through as many joists as you want - Joist Hole Reinforcer. Full disclosure, this is a product that I sell for the exact application in question. There are other ways to reinforce joists with holes, but I believe this is the only one that is code compliant out of the box. Hope this is is useful and helpful to others, not intending to spam.