Dimensional Lumber vs. Wood I-joists Notching

The rules are different on Mfg. I-joists vs. Dimensional Lumber. It is in all my education and InterNACHI education.

But the instructor on the Free NYS decks inspection Webinar says No, the rules are not different when I ask that question.

And so, I Googled it and yes, and most of you already know this…but I don’t know why he disagreed, because all the literature says they are different…

“Engineered joists , also known as I -joists , are lightweight structural members that address many of the issues with traditional joists. They have a top flange and bottom flange with a sheet of plywood in the middle. Engineered joists and solid-lumber joists have different notching and drilling rules .”


And the link is right in the middle of the quoted text from a simple copy and paste on my edit box.

Its just like those tough instructors you had in School. They disagree with you no matter what.

It even says that in the InterNACHI courses and guest speakers we have had. FYI.

And I was suprised when I learned this a few years ago. So, I have to question it to be certain.

Does anyone agree? Notching rules are different for Engineered Wood I-joists vs. Dimensional Lumber. Right? Thanks for Reply. It is plywood in the center of the I-joist.

They are different, but a good example of why inspectors should do their own research.