Removing An Old Bathtub

MATERIALS: 1x4 boards

TOOLS: Safety glasses, leather gloves, hammer, tarp, sledgehammer, reciprocating saw, pry bar

Make sure you have plenty of room to work before you tackle tub removal. You’ll need a clear space at least 3 feet deep when pulling the tub straight out from the wall. You need to be able to work around the tub when it’s away from the wall. It’s a good idea to remove other plumbing fixtures such as the sink or vanity and toilet.

MAP YOUR ROUTE. Measure the width of all door openings and the hallway along the path for removing the tub. Not only is this important for removing the old tub, it’s essential for bringing in the new one. Tearing up your bathroom to remove the old tub, then discovering that the new one won’t fit through the halls or doorway is not a pleasant way to spend the weekend.


• Turn off the water at the main water shutoff. Drain the water supply lines by opening a faucet below the tub level.

• Remove the faucet handles, spout, and drain.

• Cut away at least 6 inches of drywall above the tub on all sides. Remove the screws or nails holding the tub flange to the studs. If you find a galvanized strip along the tub flange, use a flat bar or pry bar to remove it.

• Lift up on the front edge of the tub with a pry bar and slide a pair of 1x4s beneath it.

• Pull the tub away from the wall using the 1x4s as a skid. You’ll need help carrying the tub, especially if it’s cast iron. If you’re not saving or reusing a cast-iron tub, cover it with a tarp and break it into pieces with a sledgehammer. Wear safety glasses when hammering, and put on gloves when you’re picking up pieces of the tub: they’re sharp—very sharp. Cut fiberglass and polymer tubs into pieces with a reciprocating saw.

WATER HAMMER ARRESTER - Though not generally required by code, it's a good idea to install a water hammer arrester when plumbing a bath. Pipes often make a loud bang, called water hammer, when you turn off a faucet. Water hammer arresters absorb the increase in pressure caused by turning off the water, keeping everything quiet in the walls.

Give yourself plenty of room to work when you're removing a tub. Cut away at least six inches of drywall above the tub.

Installing A Bathtub In An Alcove

MATERIALS: Copper supply pipe, copper fittings, integral stops, copper tube straps, faucet assembly, shower tee, solder, flux, soldering kit, PVC drainpipe, PVC fittings, PVC P-trap, tub overflow and drain assembly, PVC primer and adhesive, bathtub, galvanized nails, 2x4 blocking, 1 x3 ledger strips, silicone caulk

TOOLS: Propane torch and striker, tubing cutter, fiberglass flame barrier, hammer, electric drill, spade bits, screwdriver, saber saw, PVC cutter, tape measure, carpenter’s level, pencil, gloves, safety glasses

Place a blanket or piece of old carpet in the bottom of the tub to protect it while you’re working. Dropped tools can easily crack or chip the finish.

Installing a tub isn’t rocket science, but it does require solid plumbing, carpentry, and sometimes, tiling skills. Before installing a tub, review everything that affects the project. Make sure you’ve qualified yourself for the job and are comfortable attempting it. Measure the width of doors and passages. Make sure you not only can get the old tub out, but also that the new one fits into the bathroom. Rather than have a contractor take over a halfway-completed project, it’s better to consider hiring one before you begin. This is also one job where it’s great to have a helper to hold and haul.

Install an access panel behind the faucets and supply pipes so you won’t have to remove the wall to work on them. Include shutoff valves or integral stops on the supply plumbing run. They isolate the plumbing from the rest of the house. Check local codes regulating installation of scald guards. They prevent someone from being scalded in the shower when cold water pressure changes, such as when a toilet is flushed. Bathtubs are heavy. Have someone help with the installation.

MAKE A BED FOR MODERN TUBS - A cast-iron tub is plenty strong on it's own, but tubs made of enameled steel, acrylics, fiberglass, and similar materials flex when you fill them with water. Give them some extra support with a bed of sand mix. (Check the warranty to make sure the mix and the tub are compatible.) Sand mix is similar to concrete mix without the stones. Mix according to directions, and pour on the floor directly beneath the tub before you position it. Cover the wet mix with 6 mil. plastic sheeting to prevent any possible reaction with the tub.

Place 2x4 blocking behind the spout and the fixture to securely mount them to the wall.

1 FRAME THE WALLS AND RUN THE SUPPLY CONTROL RISER. Frame the walls so that the alcove opening is just large enough to slide the tub into place. Leave a gap of Vs inch or less at the head and foot of the tub. Install plumbing for the risers, faucet, and showerhead. Place 2x4 blocking as needed to secure the faucets, spout, and showerhead.

2 MEASURE THE OPENING. Before you buy a tub, measure the alcove's width and length, and buy a tub to fit. Once you've run the supply lines and cut the access hole, slide the tub into the alcove for a test fit.

3 CHECK FOR LEVEL. Lay a carpenter's level on the tub to check for level. If you are not setting the tub in a bed, you will need to shim the tub to level it. Because wood shims will rot when exposed to moisture, use flattened copper tubing or plastic shims. Once level, mark the top of the nailing flange at each stud.

4 DETERMINE THE LEDGER BOARD MOUNTING HEIGHT. Ledger boards are required for fiberglass and polymer/acrylic tubs. Measure the distance from the top of the nailing flange to the underside of the tub rim inset. Subtract that figure—about 1 inch—from the marks on the wall studs and mark the ledger board mounting height.

5 CONNECT THE P-TRAP. Install the drainpipe and P-trap if they have not already been roughed in. Cut an access hole into the subfloor. Make it 4 to 9 inches wide and extending 12 inches from the center of the end wall. Connect the 1 1/2-inch P-trap below the floor level so that the slip nut fitting is centered directly under the overflow and drainpipe on the tub.

6 DRY-FIT THE TUB DRAIN AND OVERFLOW. Following the manufacturer's instructions, assemble the drain system so that you can measure and trim the drain tailpiece to connect with the P-trap.

7 TRIM THE DRAINPIPE. The tub drainpipe will slide into the pressure fitting on the P-trap. It may be necessary to trim the pipe to fit smoothly. Check the manufacturer's instructions for installation.

8 CONNECT THE OVERFLOW and drain to the tub and set the tub in place.

9 INSTALL LEDGER BOARDS. Cut the ledger boards to fit the alcove. Then use wood screws or galvanized nails to attach them to the studs following the marks you made in Step U. Install the boards in sections if necessary to make room for any structural braces at the ends of the tub. Double-check for level.

10 SET THE TUB INTO PUCE. Seat the tub on the ledgers. The tub must sit firmly on the ledger strips and the drain must fit smoothly into the P-trap. Nail through the predrilled holes using galvanized nails. (If there are no holes, drive the nails so that the nail head anchors the tub to the studs; see above inset.] Protect the tub with cardboard placed underneath a towel or rag.

11 INSERT THE DRAIN PLUG LINKAGE. Install the drain linkage through the overflow opening. Attach the overflow cover plate to the mounting flange with screws. Test the system for leaks and schedule a city inspection, if necessary, before you finish the walls and tile.

12 CONNECT THE FAUCET HANDLES AND TUB SPOUT. Use tub-and-tile caulk to seal around the faucet handles and tub spout. Apply a bead of caulk around the edge of the tub. Turn the water on and check for leaks.

TILING THE WALLS - Planning to tile the walls? Tiles need a solid surface that can support their weight. Also, moisture may get behind the tiles, so the surface needs to withstand moisture damage. Use cement backerboard for the substrate; it's typically required by code.

Installing the drain assembly can take a little fiddling before you get it exactly right—be patient and take your time. Limit frustration by test-fitting everything before you do the final installation.

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