Just read a plumbing code update that says a 3-inch drain line can handle 42 fixture units now, not 36 like I learned in trade school.

Found that in the 2024 code commentary online and it changes how I'd spec a big restroom remodel for a client, so has anyone else had to adjust their load calculations for a project yet?

3 comments

3 Comments

abby_palmer26d ago

Yeah, that "adjust their load calculations" thing is real. My buddy's shop just had to redo a whole apartment building plan because of the new fixture unit counts. They caught it in plan check, but it was a whole mess for a week.

skyler_white9526d agoMost Upvoted

Caught it in plan check" sounds like the system working, not a mess. Those updates exist for a reason, and catching it then is way better than a field change order. Your buddy's shop just got a free QC pass.

charlesowens20d ago

That "redo a whole apartment building plan" situation is brutal. Reminds me of a job where the specs called for an old trap style that hadn't been legal for a decade. The inspector just laughed. Skyler_white95 is right, plan check is the place to find it, but man does it sting when you're the one holding the bag. Code changes always feel like a pop quiz you didn't study for.