Hello, I would like to know if there is a way to install a toilet on a concrete slab (basement) that has radient tubing installed in the slab? I have a 3"PVC pipe sticking out of the slab, In hindsight I wish it were 4", and I wish I took pictures of the radient tubing before pooring the concrete. Thanks

Do you know if the three inch pipe was meant for a toilet? If so, you can install a twist and set clostet flang that will fit inside the pipe. The only concern here would be anchoring the flange to concrete. IF radiant pipeing was tied down to rebar, then you should be able to use up to 1 1/2 inch concrete anchors to secure flange to floor(assuming your poor was at least 3 1/2 inch. Probably was four inches. You could make a platform(out of 2x4 laid flat) for the toilet to set on, glue the studs down instead of acnchoring with bolts, then you will be able to anchor the flange to wood platform. This way you will not have to drill into concrete at all, meaning you don't have to chance hitting a heating line(causing much more work). Please let me know what you think.

Good Advice MGD77...

You can also install the toilet on bed of grout or thin set. Let dry for a day or too. This way, no bolt, and drilling into the concrete slab, are necessary.