Raising Up a Toilet Flange

Hello all,

My father has built a raised bathroom floor to allow for an easy step into a whirlpool tub. The Problem: this has created a step down to get to the toilet. We would like to raise the height of the toilet floor about 8 inches. The woodwork is easy, but I'm not quite sure how to raise the toilet flange.

What's the best way to raise the height of the toilet flange up 8 inches?

Thanks!!

 

Is the current floor a slab or wood floor? Basically, if you take the existing flange off, put a coupler on it and a short piece of pipe (high enough to go above the new floor), finish it off, then cut it back and install a new flange on the pipe.