This is my first question and I am a female without much knowledge of plumbing.
We have a half bathroom that we want to add a shower to. The floor is slab (concrete) and we know that we are going to have to break up the floor. Can we hook up to the toilet or sink drain or will we need an entirely new drain. We know that it has to be vented too.

Hey Missy,
You will cut into the lavatory drain line with a 2" wye or combination wye and eighth bend and run to a 2" trap placed directly under the place the shower drain will set. You will run a 2"raiser off the trap upo a few inches above the floor line. When you're satisfied that the trap and raiser's positioned correctly then you may proced to float a cement patch over the open trench and trap/raiser. By connecting the shower drain to the lavatory drain, the shower will be wet vented by the lavatory vent. Good luck, Tom