I live/work in a new "demo" construction. The landord/self-contractor is responsible for the subfloor/underlay.

The floor is 3/4" plywood over steel beam frame. The underlay in the washroom was put in after the fixtures (the floor wasn't complete for occupancy and the washroom had to at least be useable). He feels the "subfloor" (underlay)is complete (using 1/4" mahoghany), but he did rough cuts around the toilet and fixtures. I always thought that flooring should go under toilets/fuxtures for a nice finish, good seal, and ease of replacement (in case the replacement fixture has a different shape base)? Which "technique" is correct?

Also, I will probably finish the floor with tile. Should it go under or flush to the toilet/fixtures? What if I decide on using linolium?

thanks for your help.

Ron