Percentage of drain pipes - 3 or 4 inch

[NotNewbie]

A question about wax free gaskets in another post got me thinking about drain pipe sizes. Every drain pipe i've ever encountered was 3 inch diameter. i would estimate that probably 80% of the drain pipes in the USA are 3 inch, as compared to 4 inch. would you agree?

only Fluidmaster makes the Universal 3" and 4" diameter wax free gasket. Fernco only makes 3" OR 4" ...

 

[Terry]

Most water closet flanges are 4"x3", sort of like a shallow funnel toward the smaller 3" pipe.
And then there are the 4" flanges.

All of the wax I see is 4" which works with all of the flanges.

 

[Sponsor]

 

[Gusherb94]

A question about wax free gaskets in another post got me thinking about drain pipe sizes. Every drain pipe i've ever encountered was 3 inch diameter. i would estimate that probably 80% of the drain pipes in the USA are 3 inch, as compared to 4 inch. would you agree?

only Fluidmaster makes the Universal 3" and 4" diameter wax free gasket. Fernco only makes 3" OR 4" ...

I think it depends on the area your in and the age of the buildings, in chicago where my parents apartment building/store is which is an early 1900s building three of the four toilets sit on a 4" drain line and i would say a very high percentage of toilets in chicago sit on a 4" drain and not 3", but where we live in the suburbs all the houses are newer and all have 3" drain lines to the toilets.