Nominal = Approximate
Actual = Reality
A 6in nominal pipe in a 6″ light gauge metal frame (LGMF) wall. Sounds like it’ll fit, right?
Wrong. Why?
Pipe material, service type, function, and the supports (hangers) all impact how much space different piping systems need. It’s important to understand this to plan for the correct size wall.
Material: Is it cast iron? Plastic?Type and use case: For cast iron, is it service weight? Extra heavy? No-hub?
Hangers and supports: Where can these be mounted? How big are they?
How do you learn how much space you need? Look through the specs. What are some of the basis-of-design (BoD) manufacturers? Charlotte Pipe is a good one. Take a look at their website. The catalogs show how large everything is.
“But it’s only a little bit different! Why are you making such a big deal out of this?”
Because bulging cracked drywall is never a good look.