Actually, I hit a slab. I'll start from the beginning.
We're putting a half-bath in a small 3 bedroom/ one bath house built in '63.
Where the new half-bath is going: it's an area that at one time used to be a patio adjacent to a carport. 20 or so years ago, this area was transformed into a bedroom and adjacent laundry room. So we tore out a wall of the bedroom to join the laundry room and make it big enough to accommodate a pedestal sink and toilet. Everything was fine until we pulled a piece of the floor up to take a look. There is a concrete slab. We drilled through it with a 1/4" bit just to see how thick it was and what was underneath. It's about 6" thick with about a foot and half crawlspace underneath. The big mystery is why they used a rebar mat to pour a slab onto, when they could have used wood floor joists to accomplish the same thing.. But that's another....
So I need a core drill right? I mean I have to get through it to plumb the toilet and sink. Here is a pic. In the pic you can see the hot and cold for the washer, the drain and the vent, which we were planning to tie into and go to septic. I'm open to any other suggestions.