3" vs. 4"

Old 08-15-01, 09:39 AM
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I'm plumbing a new house. I see 3 inch toilet flanges and 4 inch flanges. What size do I use? What size does a standard toilet use? If I use a 3 inch main waste stack can I use a 4 to 3 inch closet bend with a 4 inch toilet flange?
Also would it be wise to run a 3 to 2 inch reducer above all drains to have a 2 inch vent pipe come out the roof, or is it better to run the 3 inch main waste vent out the roof?
Old 08-15-01, 07:26 PM
Mike Swearingen's Avatar
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Call your Building Inspection Department for your local code (and your permit).
When plumbing a drain/waste/vent system for yourself ...BIGGER is better. Go with 4" from top to bottom.
Never step down a drain line or vent. Always increase the size of the drain pipe as you go out from fixtures.
Look in the "Repair/Fix-It" above under Plumbing for a little guidance (and basic code).
Good luck!

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