Presuming it is a cement slab, it would require the use of a jack hammer to run a drain line for the shower - which should be able to tie into the toilet drain.
you are correct-we are counting on breaking up concrete to connect the drains...but I just have a feeling it is very expensive and complicated-hopefully I'm wrong. So I was wondering if anyone in Hometalk has ever done this??
Its not complicated, but it does carry a higher cost than if it was in a wood floor system. I would recommend making a list of your wants v.s. needs to present to the contractor. In addition.. a budget. If they are an experienced professional, they should be able to help you get the most for every dollar that you have to invest. For now, dont sweat each element until you discuss labor costs (assuming you are hiring it all out)
as a 1/2 bath I would assume it is 1-toilet and 1- lavatory.
Is it a finished 1/2 bath or just rghed in? If it isn't finished then it would be a fairtly easy job of cutting the floor and adding a shower drain. If it is finished then the cost will go up a bit but would still be fairly easy for a proffesional..
you will also want to make sure hot water is readily available.
Adding that will require cutting through the slab...the easiest way will be with a diamond blade "slab saw"...once that is done they will need to excavate the soil, tie in then repour the slab. Around here that would run 800 to a grand.
its not finished (& easy access with walk-out basement) but even at 1k its not as bad $$ as I feared