# toilet drain vertical minimum

Discussion in 'Toilet Forum discussions' started by glebbscout, Nov 23, 2006.

1. ### glebbscoutNew Member

Joined:
Nov 23, 2006
What is the minimum vertical height between the bottom of where the bend starts in the horizontal drain pipe and the flange? Assume the drain pipe is 4" interior dimension and flange is 1/4". The center of the drain pipe is only about 18 inches from vent stack so not a lot of slope to it.

Diagram:
_ (flange sitting on floor)
min. vertical? l
________ (horizontal pipe line)

Thanks.

2. ### MikeyAspiring Old Fart, EE, computer & networking geek

Joined:
Nov 8, 2005
Occupation:
Consumer
Location:
Central Florida
It wouldn't be too hard to lay a closet bend against a flange in any of the big box stores to get a rough idea. I'd guess something like 6-7".

4. ### glebbscoutNew Member

Joined:
Nov 23, 2006
yes, but...

I guess what I mean is: is it acceptable from a plumbing perspective to have such a short distance for the water etc. to flow from the toilet, into the drain before it hits the bend? If the flange measures 2 inches, roughly, top to bottom, plus the 4 inches until the bottom of the pipe, that's not much of a drop before it hits the bend. Does that matter?

5. ### hjModerator & Master PlumberStaff Member

Joined:
Aug 31, 2004
Occupation:
Plumber
Location:
Cave Creek, Arizona
height

The minimum distance is as little as you can cut it and still get the flange to slide over with a good seal. Which usually means the riser has to be as long as the flange is deep.

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