I am putting in a new bathroom floor and replacing the toilet. I am adding a half inch plywood and ceramic floor tile (grouted). How do I extend the height on the soil pipe?

What is on the floor now? Will you be removing that material and replacing it?

Is the WC flange the concern and not the pipe? If so, Specialty plumbing makes ring shims to raise the WC off the floor. Use a dripless wax ring for proper sealing.