: can above be installed without knocking hole in floor for drain? closet and sink drains are already roughed in. How high would above installation have to be to facilitate trap above floor?Calvin, Either a tub or a shower would require a p-trap on the drain to prevent sewer gas problems. The installation would have to be7-1/2 in height. Since the drain will need to tie into the pipes in the ground I would suggest the services of a concrete sawcutter. Regards, Terry Love