"david" wrote in message
oups.com...
Hi,
I am remodeling a bathroom in the basement and after removing the
toilet, found the flange was very corroded and old. I tried scraping
what I believed was a wax ring away to see where the flange began and
pieces of the flange itself came apart (metal).
The pipe has an interior diameter of about 3.5 inches. It's hard to
tell what type of metal it is but I know another shower drain project
(right next to it) revealed copper drain pipes.

My question is, how difficult is it to replace this flange? Does the
flange have to be sealed to the original pipe via some type of welding
or can I simply use a plastic flange, fit it inside the original and
screw it into the concrete with anchor bolts?

Thanks

If the toilet is on a concrete floor, from a practical viewpoint, you don't
really even need the flange. Our house was built in the early 70's and the
downstairs bathroom on a concrete slab has the 4" cast iron soil pipe flush
with the fllor with no flange on it. A master plumber told me this was fine
and met code at the time. As long as you anchor the toilet to the floor so
it doesn't move around, you can just use a wax ring w/plastic sleeve and you
should be fine.