Floor Drains

plumb.bob.down

Okay, I know an Industrial floor drain (a.k.a. manufactured floor drain) would "dump" into a 4" waste normally on a job because you can't decrease the size of the waste pipe it dumps into, BUT, on the KY Master Plumber's Exam, everything is supposedly sized by fixture unit count.

I know a Water Closet is on a 3" waste regardless of the situation (when only 6 F.U. and the code just requires a 2" waste for 6 FU), and a 3 Compartment Sink w/ flo-control and a grease trap HAS to dump into a 2" waste (when by code, it's only 2 fixture units and SHOULD dump into a 1.5" waste if not dumping into a waste line that's underground).

So what I'm getting at is what else besides the grease trap setup w/ the 3-compartment sink, and the toilet, requires a mandatory size?

The manufactured floor drain require a 4" waste? not a M.F.D. system, just an individual one.


THANKS!

Double-A

Well, don't forget those are minimums.

Is your flush-valve water closet still rated at 6 dfu or is it 8... In Arkansas its 8dfu.

The other thing to consider is trap size. A tub on the second floor with an 1-1/2" trap is considered 2dfu, but if you put a 2" trap on it, its considered 3dfu, and the tub dfu does not change when you have a shower head over it.

There is a difference between drainage fixture units and fixture units. The Lowflo supply valve over your 3 bowl sink is meaningless. The only concern is what size trap and drain will service it. That is driven by dfu when its listed, and by trap size when its not.

The only reduction you're allowed is a 3x4 closet bend, and its technically is not a reduction according to most model codes, even if it physically is a reduction.

Mandatory sizes will be listed in your code. Where they are not you will use trap size to determine drainage size.
Sometimes trap sized are mandated as well, like on tubs. You can't use smaller than 2" underground, so a first floor tub would get a 2" trap, but a tub on a second floor, or over a crawl space can use a 1-1/2" trap.

Got it?

__________________
"My clients’ wishes are the center of my attention." -- David Guido, a contractor in Woodstock, N.Y.
New York Times, July 20, 2006

plumb.bob.down

The kentucky code is a code all it's own a i think, i mean parts of it may come from the IPC and what-not.


All waste and stacks are calculate by fixture units. .

i got everything down, except the floor drain

i know it's mandatory for the grease trap system to dump into a 2" waste and a w/c on a 3" waste.

see, on the ky master's test, everything has to be right on the nailhead. the furthest fixture away on the branch will dump into the smallest waste pipe size, then as fixture units get higher, the waste pipe size increases.

i was just wondering about the floor drains.

Double-A

I truly do not know the 'nail head' answer to that question, but, I would be greatly surprised if it was not listed specifically or listed by trap size.

Your KY code is online and I found this:




Floor drain in a utility room, basement, or toilet room = 3". Industrial Floor drain 4". An MFD for the purposes of the KY code is defined as "see Industrial Floor Drain"

Take care with the basement one however. The code says it must be 'adequately sized to serve its intended purpose' or some such language. So be sure to read the whole question before deciding its 3".

Also
Good Luck!

p.s. The link to your KY code is http://www.ohbc.ky.gov/NR/rdonlyres/...CKYplb2007.pdf

Its a PDF file so you search it.

__________________
"My clients’ wishes are the center of my attention." -- David Guido, a contractor in Woodstock, N.Y.
New York Times, July 20, 2006

plumb.bob.down

I know that man, lol

What I'm getting at is some fixtures, on the isometric drawing on the master's test, REQUIRE a certain size waste.

I'm talking about branch drain size, not FIXTURE ARMS, lol.

Like a toilet requires a 3" (even though it's only 6 F.U.) and a Triple bowl sink (w/ flo-control and a grease trap because it's required on a triple bowl sink) dumps into a 2", branch drain, even though it's only 2 F.U.

Certain fixtures require a certain Branch Drain size.

I guess, I'll just stick with the w/c dumping into a 3" and a 3-bowl sink dumping into a 2" and size the rest of the branch drain by fixture units.

I took this test once before and got an 88 on the code and a 60 on the drawing, and it was due to sizing the branch drains by the fixture arm size from the fixtures. Although, you would do it that way in real life, but they want you to size everything (besides the W/C and 3-bowl sink) by FIXTURE UNITS

Double-A

If you made an 88 on the written portion of the test before, you're gonna do fine this time.

Good luck, but I'm not sure you need it. Sounds like you have it down.

__________________
"My clients’ wishes are the center of my attention." -- David Guido, a contractor in Woodstock, N.Y.
New York Times, July 20, 2006