American standard bathtub drain leak

[piezomot]

Contractor installed new American standard bathtub in my house (second floor) and probably did not fully tested it. New tiling was already done too.

Yesterday I installed new faucet there and I wanted to use my bath first time. I closed the drain (this drain design has no switch but rotation handle) and started to fill my bathtub with water, immediately water started to leak from my kitchen ceiling to the wall, so I opened the drain and called that contractor. I examined the drain flange shown with the arrow on the picture and it looks solid - no motion or rotation. I am puzzled now what was causing this water leak, when the drain pipe was closed...

Contractor told me that they have to access it via kitchen ceiling to see what is wrong there. I was told that nowadays they produce copper pipes thiner and thiner (walls) so they sometimes break upon installation.

I expect them to fix the flange and kitchen my ceiling at their own expense. Good news is that I paid them only 50% now, as they just completed the job last week and did not collect full amount yet...

 

[piezomot]

Just in addition to above I would like to add that contractor fixed the problem. He found leak between bathtub and drain flange exactly as it is shown on my picture with the arrow. It looks like bathtub bottom surface where gasket is was rough and the gasket itself was very stiff. So he changed that black gasket and applied some plumbing putty to seal the gap. Now everything works fine.

Also I have found an interesting discussion on this topic here: