I am remodeling the bathroom and kitchen in a house that my wife and I recently purchased and one of the things we wanted to do was to put in a tile floor and make it about the same level as the existing hardwood flooring.
After removing the multiple layers of underlayment and getting to the subfloor we could see wood rot that needed to be dealt with first.
I have now replaced the rotted joist and am ready to start rebuilding the subfloor but before I do that I want to do whatever is needed to the drain for the bathtub since I have full and easy access to it at this point.
Here is a picture of the bathtub drain pipes (before I replaced the joist).
Since I have easy access to this plumbing now... I'd like to put in whatever should be installed and in the right way so that I end up with no leaks and no problems for a long time.