Another Shower drain to tub drain conversion

[tom-J]

Changing stall shower to tub/shower combination. Room size from drywall to drywall is 66” X 120”. I would like to install a 60” tub on the 66” wall. The back 120” wall contains a 36X36” shower base (removed), vanity/sink and toilet. The back 120 “ wall is drywall, 2x4 in front of a concrete wall. The floor is 6” concrete. The existing shower drain (plastic) is at floor level located 16.5” from drywall on back 120” wall. The drain is 17.5” from the 66” side wall and the trap portion of the drain is 9” below the top of the concrete floor. I would like to use the existing drain for the new tub. Can I cut the floor, remove the existing shower p trap and install a p trap at the tub drain for the tub tail piece then connecting the trap output to the existing shower drain pipe? If using the existing drain is possible would a plumber be able to install a 60” tub and tighten the tale piece on the tub drain to the newly installed p trap if the tub is centered in the 66” opening given that the wall by the connections is drywall 2x4 and concrete? If that isn’t possible would it be possible to tighten the connections if the tub were positioned so that the end of the tub opposite the connections was flush against the opposite wall? That would allow the connection end of the tub to be positioned 4 or 5 inches away from the wall. Is there enough room to make the connections from the side of the tub? I would then build to niche in the remaining wall space. Would like your thoughts prior to calling a plumber for a quote. thanks tom

[jadnashua]

Each tub will have its own requirement on where the trap needs to be. While they're more expensive, most manufacturers make tubs in 6" increments, so there are 66" (rough opening) tubs out there. Personally, I find a stock 60" tub very uncomfortable and installed a 6' (72") tub when I remodeled...I would have loved one even longer. Considering how long a bath remodel usually stays around, that extra expense is pretty small for the increased comfort.

The drain diameter for a shower was probably 2", so is fine for a tub, but you'll likely need to tear up some concrete to get it where it needs to be. You need the drain where the tub you choose wants it, or it will likely smell and be very difficult or impossible to snake, if that ever becomes necessary.

A pro lines things up, and sets the tub. If done properly (takes some skill!), it can be done blind - i.e., with no future access, but you only get one chance to do it right - best left to a pro. If you do decide to go with a shelf or some such thing to fill out the distance with a 5' tub, pay particular attention to the waterproofing. Done right, it works fine, done wrong, mold/rot city! There are lots of waterproofing systems out there. Tile is NOT the waterproof surface; it's what's underneath that should be waterproof before the tile is even installed.

[hj]

A "plumber" can do almost anything, but let HIM relocate the trap the way HE wants it done. If YOU do it, you will probably make his job harder.