Holes in Wood truss floor joist???

What is the maximum size hole that can be put into the web of an engineered wooden truss floor joist?

Truss members and components shall not be cut, notched, or otherwise altered in anyway with out the approval of a registered design profesional.

Found it on a past post…mark I think you were thinking of Roof Trusses


No i was actually quoting the international residental building code chapter 5 (floors) code article R502.11.3


Drilling holes in I-joists. The flanges must never be cut or notched, but fairly large holes can be cut through the webs (the largest holes are permitted at midspan). TruLine Truss staff should be consulted to determine maximum diameters for holes near supports.

Huge Holes are allowable—:smiley:

Exactly…see the manufacturer’s installation info…

Thanks Guys

I ran into this same issue today with huge duct work holes drilled, looked up this post, and wham got my answer. I love InterNachi members!!