I have looked everywere and found many fixture count charts & tables which give me a total. Now that i have that number, what good is it. I am bidding a 5000 sf house w/ 2 kitchens, 1 laundry w/tub, 5 full baths and 1 half bath. I have done a fair bit of plumbing and a licence is not required in my small town, but i do want to do it correct. I am not concrened about the supply, but the waist. I allways use 3″ for drains, and thought the fixture count would help me detirmine the draine size. When do i go to 4″. Is there a chart for this?
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Yes there is a chart. My scanner is having issues so I will type a bit of it.
An easy rule to go by------ 3 toilets =3" 4 toilets = 4"
You can use 4 toilets on a 3" but only vertical once it hits horizontal it has to be 4" or larger.
Vertical horizontal
1.5" 2 1
2" 16 8
2.5" 32 14
3" 48 35
4" 256 216
“A universal peace, it is to be feared, is in the catalogue of events, which will never exist but in the imaginations of visionary philosophers, or in the breasts of benevolent enthusiasts.” —James Madison
Well, things change pretty fast up here. The owner just added another full bath, so it is 3 full on the ground floor, 2 full and 1 half on the second. The 3 on the first are grouped together and one on the second will be "upstream" of the 3 on the 1st, so the 4th in line on the horizontal will increase to 4''. The other 2 on the second will be 3'' to where they tie into the 4'' main, then 4'' to the city. Does this baciclly sound correct? I guess it is time to clean out the office/shop/ tool box/truck and find that code check, or maybe i loaned it to my 2nd cousin-in-law...? I'm sure all of us have one relitive who has a habit like that, borrowing w/o asking and never returning until i have looked everywhere! Or maybe cus has the drill that went missing last summer... I better call him.
Anyway, thanks for the help.
Yup.
Start at the top & work towards the sewer main as soon as you get to 4 toilets then the line needs to be 4".
Like I said there are ways to put 4 toilets on a 3" line, but the simple rule of 3 = 3 & 4 = 4 works great without it being overkill.“A universal peace, it is to be feared, is in the catalogue of events, which will never exist but in the imaginations of visionary philosophers, or in the breasts of benevolent enthusiasts.” —James Madison
The short answer is, yes, there is a chart. What code are you under? I don't have any charts in front of me, but I'm guessing you're going to need to go to 4" at some point in that system. All of my plumbing books are at the house I'm building, and my experience sizing drains is limited to that house. But I was able to count up my fixture units and figure out my drain sizes with a copy of the IRC 2003 book. The Code Check Plumbing from Taunton would probably have that info too. ( http://www.taunton.com/store/pages/070679.asp )
If I remember, I'll bring some books home tomorrow and see if I can help you figure out the answer, if someone else hasn't already.
-Rich
Edit: looks like you got an answer...
Edited 2/18/2007 2:33 am by rfarnham
I do have a code check, someplace... Thanks for the info