There can be many benefits to replacing your bathtub. A brand-new tub can add comfort and spruce up the look of your bathroom, not to mention avoid issues such as leaky tubs, eroded finishes, mold, and mildew. While you don’t necessarily need a plumber to install one, it is certainly recommended to have someone with plumbing knowledge assist you. With someone to help and some preparation, you can remove and replace your bathtub in a day. Here’s a look at what you need to know about bathtub replacement before you start.

DIY Guide to Bathtub Replacement

Steps to Bathtub Replacement

1. Preparation

You’ll want to gather some protective gear such as goggles, work gloves, and hearing protection. If disposing of your old tub, contact your local sanitation or recycling company about how to proceed. The planning process also requires measuring your current bathtub. Most standard tubs are 5 feet by 30 or 32 inches wide. The size of tub you choose should approximate your measurements, as shower surrounds, tiles, and other materials can result in lower values.

Before you start, you need to choose a tub with a left or right drain opening. This is determined by where the drainpipe is positioned, which you can see when facing the alcove.

2. Choose a Tub

Bathtubs range from simple to rustic, to luxury. Common types include cast iron, acrylic, steel, cultured marble, and fiberglass. The styles available on the market range from freestanding and walk-in tubs to clawfoot, soaking, and jet/whirlpool bathtubs.

3. Remove the Old Tub

To remove the old bathtub, follow these steps:

  • 1. Shut off the water supply to the tub, your bathroom or, if necessary, your entire home. While no water lines are connected to the tub itself, accidentally turning a valve during the process can result in a soaking.
  • 2. Disconnect drain components such as flanges, drain stoppers, and overflow covers. A tub drain wrench helps remove the flange while a screwdriver aids in removing the waste/overflow cover; remove the tub spout by twisting it counterclockwise.
  • 3. Remove the drain assembly by opening an access panel or cutting away a patch of drywall behind the overflow valve to the floor. Disconnect the drainpipe below the tee with channel lock pliers; once the nut is loosened, unscrew the unit by hand.
  • 4. Separate the tub from the wall by, first putting on safety glasses and gloves, and then cutting a section of wall about 6 inches above the tub on three sides. You’ll need a grout remover tool to remove tile, a drywall saw to remove a section between the grout line and tub, and utility knife for a cement backerboard (use the knife to cut away caulk between the tub and floor). Use a pry bar to remove screws or nails from around the tub.
  • 5. With another person, remove the old tub. While one person lifts the front edge, slide two 1×4 boards underneath it. Slide the tub out of the alcove. Then remove any stringer supports on the wall, clean the area, and dispose of the old tub.

4. Install the New Tub

When your bathroom is ready for the new bathtub to be installed, here is how to proceed:

1. Keep the new tub packaged until you’re ready to install it. When opening the package, cut a section of cardboard and place inside the tub to protect the surface. Check the subfloor and use shims to even the tub if it’s not level. Pencil a reference line on the studs on all three sides, and then move the tub aside.
2. Install a 2×4 stringer to the studs to support the tub. When you know the height, measure the same distance below the reference line, which is the stinger’s top edge. Cut a section of wood the length of your tub and attach it to the wall studs with deck screws.
3. Place the tub on its side and connect the overflow drain assembly; follow any manufacturer’s instructions included. Place some plumber’s putty on the underside of the flange and position the drain shoe on the underside of the tub. Next, screw the drain flange onto the threads and tighten with a drain wrench tool. Connect the overflow valve, attach the cover plate to the overflow elbow and gasket, and connect the overflow pipe and drainpipe with a tee. The drain strainer is then placed on the flange.
4. Move the tub back in place and connect the drain. The flange should be resting directly on the stringer. Check that the drain/overflow plumbing and rough-in drain outlet are aligned, and then connect and tighten the pipes.
5. Verify the flange lines up with your reference marks and secure it on all three sides, holding it down with the head of the fastener (use roofing nails or galvanized screws). Install the drywall, tile, or tub surround when the bathtub is in place and reinstall the baseboard and finish molding. Next, reattach the spout and turn on the water supply valve.

*Do not use the tub for 24 hours.

Cost of Bathtub Replacement

Replacing a standard bathtub can cost anywhere from $1,400 to $7,000, according to Angie’s List (the average cost is $4,150). However, you could spend just a couple hundred dollars for a simple tub and no plumbing modifications. Some luxury tubs can go for $10,000 or more. 1 Clawfoot tubs are generally the most expensive while jet/whirlpool and soaking tubs can set you back quite a bit as well.

However, lightweight fiberglass tubs are generally affordable. Steel, acrylic, and cast iron vary considerably in price depending on the quality of the tub and work to be done.

Factors affecting cost include alternative size and shape requirements, the material you choose, and labor. A plumber may charge $45 to $200 per hour while an electrician may charge $50 to $100 per hour. Tile professionals can charge from $40 to $60 per hour.

Contact Express Plumbing Heating & Air

We are Boise’s leading plumbing/HVAC services company and can provide any help you need with bathtub installation near you. For professional advice and assistance, and information about specials and financing, call us at (208) 398-0309

Brad Jordan

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