Is it possible to make a drain to the bath from the supply line at home?

Good afternoon, Eugene. Yes you can.

It is only necessary to consider two factors:

1. The bath will be the main pressure. If not enough, a booster pump can be installed. It is placed in a convenient place, the point of entry of the pipeline. Despite the low price, it has three switching modes: automatic, continuous operation or completely disabled. The Oasis model has proven itself, the appearance in the photo 1. The cost is 2000-2500 rubles, the lifting height is 6 meters, the productivity is 40 l / min. I am sure that the information from our article about pumps.
2. At home, the pumping station will operate normally. It is necessary to take into account only new losses, as well as the simultaneous use of water in the house and bathhouse.

Good luck