Holes in I-Joists too large?

Does anyone know maximum hole sizes in I-joists? This is new construction and I need to know how to report this to my customer.

Depends on the Manufacturer and location of the holes within the joist.
This may help you here;


Awesome! thank you for your help!!

Often those joists come with pre-drilled openings for ductwork and piping, which appears to be the case here. Because of the uniformity of the holes, I would personally would not call this out. At best, I would refer the customer back to the building plans.


I agree Brian, those look to clean-cut for anyone to have done them.


Thank you Brian!!

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