Here is the situation:
Minnesota state: UPC
Question is about the size of the main sewer line exiting the building.
Existing main sewer/drain line is 4".
Have to rough-in 32 bathrooms in a building.
Each bathroom has a Toilet (3dfu's) , Shower (2dfu's), Lavatory (1dfu).
6dfu's per bathroom total.
Have 32 bathrooms. i.e, 32x6= 192 dfu's Total.
According to table 703.2, Minnesota plumbing code, Max DFU's for a 4" Horizontal pipe sloped at 1/4" per foot is 216 DFU's.
So far so good.
Here's the kicker, there are 2 existing public restrooms in the building, that ARE going to remain in place. Another 24 DFU's.
And there is going to be a large commercial kitchen. No final plans yet, but expect atleast another 10 DFU's.
New total is 226 DFU's.
Very close. Do we need to upgrade to a 6" main drain line, after all the branches converge?
I think (correct me if I'm wrong), that the table 703.2 already is sized taking into consideration intermittent waste flow.
(Personally too, I think the 4" might be able to handle all the load, based on intermittent usage.)
How do I show the JHA (Jurisdiction having authority) on my permit application plans that the 4" is adequate (if it is).
Or should we get plan to upgrade to a 6" line to be conservative?
Just want to hear your experiences and suggestions on sizing pipes on large jobs. When did you work with, or upgraded to a 6"?
DWV will be done with PVC.
Minnesota state: UPC
Question is about the size of the main sewer line exiting the building.
Existing main sewer/drain line is 4".
Have to rough-in 32 bathrooms in a building.
Each bathroom has a Toilet (3dfu's) , Shower (2dfu's), Lavatory (1dfu).
6dfu's per bathroom total.
Have 32 bathrooms. i.e, 32x6= 192 dfu's Total.
According to table 703.2, Minnesota plumbing code, Max DFU's for a 4" Horizontal pipe sloped at 1/4" per foot is 216 DFU's.
So far so good.
Here's the kicker, there are 2 existing public restrooms in the building, that ARE going to remain in place. Another 24 DFU's.
And there is going to be a large commercial kitchen. No final plans yet, but expect atleast another 10 DFU's.
New total is 226 DFU's.
Very close. Do we need to upgrade to a 6" main drain line, after all the branches converge?
I think (correct me if I'm wrong), that the table 703.2 already is sized taking into consideration intermittent waste flow.
(Personally too, I think the 4" might be able to handle all the load, based on intermittent usage.)
How do I show the JHA (Jurisdiction having authority) on my permit application plans that the 4" is adequate (if it is).
Or should we get plan to upgrade to a 6" line to be conservative?
Just want to hear your experiences and suggestions on sizing pipes on large jobs. When did you work with, or upgraded to a 6"?
DWV will be done with PVC.
