DWV has to be Sched 40
I'm having a disagreement with a friend of what pipe is proper for drainage from sink, tub and toilet. He says he has a friend who is a licensed plumber that says you can use sched 30 pipe. And truthfully, I don't really see why not. However a few things make me question it. Why have all the houses I have built, when I was a foreman for a construction company, have sched 40, I know the builders I worked for are so penny pinching, that if they could've gotten away with saving money by using sched 30, they would have. Also, an even better reason why I think it has to be sched 40 is that when I did septic tanks and fields, when the sewage enters the tank, it has to be sched 40, also when it leaves the tank is sched40 and the lead pipe and header has to be sched40, but then all the runs for the actual seepage is perforated sched 30. So it doesn't make any sense that the drainage from each fixture can be sched 30, but has to switch to sched 40 to leave the house and enter the tank, then to leave the tank to the septic field, then after that switch back to sched 30. I am in Michigan, if the codes vary that much. Any help will be greatly appreciated.
I'm sorry, I'm sure I know, but for whatever reason I cannot remember, as I do not do much plumbing...what is DMV?
It's DWV, drain, waste, vent...
Important note - I'm not a pro
Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014
The p traps can be thinner here, but nothing else. Some of the cheap tub overflows are thinner too, but I don't like them, many codes say no on the thinner traps and overflows too. Inside the house sch 40.
Last edited by construct30; 07-11-2008 at 02:16 PM.