Replacing your bathtub can result in a dramatic improvement in the look and function of your bathroom. A DIY project can save you about $2,000 on average for labor. But a tub can range from a few hundred dollars to up to $10,000 depending on the type that you choose. It’s therefore important to know how to properly handle bathtub replacement.
Removing the Old Tub
1. Choose a Replacement Tub
There’s no point in proceeding if you haven’t picked out a new tub. Start by measuring the bathroom alcove so you can choose the right-sized unit. A standard bathtub is 5-feet long and 30- or 32-inches wide. Your measurements might read less, but the tub size should be as close as possible.
Where the drainpipe is located affects the type of tub you need. If it is on the left side, you’ll need a tub that drains to the left; a right-side drain opening requires a tub that drains to the right.
2. Make Sure You’re Prepared
Bathtub replacement is somewhat of a messy job. Be sure to wear work gloves, protective eyewear, and consider hearing protection. You’ll also need to dispose of your old tub. Check your local sanitation company or recycler for regulations pertaining to disposal and whether they offer assistance.
3. Turn Off the Water Supply
Use the shutoff valve for the tub or bathroom; if there isn’t one, turn off the water supply to your home. Turn a bathtub faucet on to make sure no water is running. Next, find a valve at a lower level and open it to relieve pressure. While the bathtub itself isn’t connected to a water line, this protects against water damage should you accidentally bump into a valve later.
4. Disconnect and Remove the Bathtub
Removing the old tub is a multi-step process. To successfully do so:
- Disconnect the Drain Flange/Overflow Cover: Unscrew the drain stopper if there is one, and remove the drain flange with a tub drain wrench. Then remove the waste and overflow valve cover using a screwdriver. Next, you can remove the tub spout by removing the setscrew or twisting the spout counterclockwise.
- Remove the Drain Assembly: Disconnect it from the plumbing by accessing the underside of the tub. Use the access panel or cut away a piece of drywall if there’s no panel. Disconnect the drainpipe, below the tee, with channel lock pliers. If there are galvanized steel fittings, a penetrating lubricant will help loosen the joints. Once the drainpipe nut is loosened, unscrew and remove it by hand.
- Remove the Tub from the Wall: You’ll have to first remove drywall and other material, to about 6 inches deep, to the wall studs. Fiberglass tub surrounds will have to be removed first. Wearing safety equipment cut out a section of the wall on three sides and along the front of the tub. Start about 6 inches above it. Pencil a guideline using a straight edge and then start removing tile (using a grout remover tool and stiff putty knife to pry it away) and drywall saw to remove a section of drywall.
- The cement backer board should be removed with a utility knife to reach the stud.
- Use a pry bar to remove screws, nails, and trim all the way around.
- Use a utility knife to cut away caulking between the tub and floor.
- Remove and Dispose of the Tub: Two people should work together, one lifting the tub from the front and another sliding 1 x 4 boards below it. These boards are used as skids to slide the tub out of the alcove. Remove any remaining stringer supports on the wall and clean the area. If the tub is made of lightweight material or porcelain enamel steel, dispose of it as a whole. Use a sledgehammer to break up a cast iron tub or a reciprocating saw to cut up steel, composite, or fiberglass tubs.
Installing a New Bathtub
When you’re ready to install the new tub, check it for damage and protect it with a section of cardboard from the package; cover the interior and exposed side. Place the leveling/sound-insulating pad on the tub’s underside, which will rest on the subfloor. Use a floor leveler to even out the subfloor if necessary.
The tub is now ready to place into the alcove. Make sure it’s level and use shims to even it out, and then mark a reference line with a pencil on the studs. This line should reach around three sides. Move the tub, set it aside, and proceed with the following steps.
1. Install a 2 x 4 Stringer
The stringer attaches directly to the studs to support the tub. Measure the height of the flange and measure the same distance below the reference line drawn to indicate the top edge of the stringer. Now cut the 2 x 4 the length of the tub and attach it to the studs with deck screws.
2. Install the Overflow Drain Assembly
Turn the tub on its side and follow the manufacturer’s instructions for installing the drain. Place plumber’s putty on the underside of the drain flange and then position the drain shoe on the underside of the tub. Screw the drain flange into the threads and tighten with a drain wrench tool.
Next, remove excess putty and connect the overflow valve by placing a rubber gasket onto the overflow elbow, which the cover plate in the tub connects to using the provided screws. Use a tee to connect the overflow pipe and drain pipe and then attach the drain strainer to the flange.
3. Attach the Drain:
The tub is moved into its final position. As you place it, avoid hitting the drain assembly, and make sure the flange rests on the stringer along the back wall. Check the alignment between the drain/overflow plumbing from the tub and the drain outlet. Connect and tighten the pipes (don’t over-tighten them).
4. Complete the Tub Installation
Check that the reference marks previously drawn and the flange line up. If they do, hold the flange down with a fastener as you secure it on three walls. It’s best secured with roofing nails or galvanized screws. Now, you can install drywall, tile, or tub surround and perform any other finishing necessary. Lastly, reattach the spout, turn the water back on, and wait at least 24 hours before using the tub.
Call Village Plumbing & Air for Help
Our experienced plumbers provide a full range of services to homeowners in the Houston area. If you need professional assistance with plumbing connections or other steps to bathtub replacement, we’re here to help. We offer a 100% satisfaction guarantee, coupons, and financing. To schedule a consultation or bathtub installation near you, request service online or call 713-678-0483.