I am wanting to add a bathroom onto a building. I am going to pour a cement slab for it. What do I do about a trap for the shower. Do I need to put a trap in the cement. The toilet and the sink will have their own traps but not sure what to do about the shower.

Thanks Dave

If wet vents are allowed in your area then connect the shower drain to the lavatory drain line where it will be wet vented. The shower trap and raiser will be installed under the pour and the raiser brought up a few inches over grade. Good luck, Tom