Hi,

I recently posted about water backing into our tub on the first floor
where the tub, kitchen sink and dishwasher all share a common drain.
After having a plumber out to snake it it started happening again today
so I snaked it myself and this time I was able to unclog it myself. I
learned a couple of tricks watching that plumber!

But the big problem is that it keeps reclogging so we must only be
opening a small passage each time we snake it. A guy I know looked at
our plumbing downstairs and pointed to a section that is older pipes
and said if I replace this one section it will cure the problems. He
thinks the insides of that pipe have mineral scale built up and that we
are only clearing a small hole each time we snake it. There is a lot
of plastic pvc that was installed when we had our kitchen and bath
renovated but there is this one section that is the old stuff.

What do the plumbing experts here think about this?

Thanks,
Steve