This is really weird. This problem several months ago and now reoccurs every few weeks. The drain in the tub will go from draining perfectly to barely draining. I keep a hair trap on top of the drain to catch the hair before it goes down the drain. If my husband opens the overflow pipe in the wall and runs the 15ft snake completely out, the drain will start draining again. The first time he snaked the pipe he got yuk out of it but since that initial snake, nothing comes out. The time previous to this back up he even followed up with draino thinking perhaps there was a clog further in. Worked just as well as the straight snaking, which works perfect, but here we are 3 weeks later, same problem this morning, just decided to back up when i showered. He got all the water out, snaked the overflow, again nothing came out but the drainage flow was restored.
This is driving us nuts.
A bit about the house, 1928 4 square,only 1 bathroom and it is upstairs. The drainage problem is only in the bathtub, does not affect the toilet or any of the sinks in the house. I would appreciate any help.