George wrote:
We have a bathtub that has a drum trap - which appears to be lead, as do
the connecting pipes. (The stack is cast iron.) The trap is leaking.

I'm thinking to cut the lead pipe on the stack side of the trap, use a
rubber coupling to join that end to PVC from there to the tub. Is there
reason NOT to do this? The alternative would be to unsolder the lead
pipe from the stack Y, and connect the PVC there. This looks like it
would take big heat, and might never get clean enough for the new joint
to seal well.

TIA,
George


All lead tub drainage was common from turn of century till 1920's.

I would cut the lead close to the stack entrance and use a
Mission-style coupling:
http://www.fernco.com/plumbing/flexi...tock-couplings
1056 series coupling to adapt to PVC.
If you can get to the stack connection, put the coupling over
the solder thimble where the lead attaches; that will help prevent
distortion of the lead. Sealant applied to the lead before sliding
the coupling on will help avoid leaks.

Use a PVC P-trap, such as #78515:
http://www.dafehr.com/Genova/gentrap...t%20(H%20x%20H)

There is one with a cleanout: #78415,
but the CO may not be accessible.

If there is room, insert a CO TEE: #71315

Jim