How to Install a Bathtub Complete Guide

Bathtub Replacement

Embarking on the journey of renovating your bathroom can be an exciting and transformative endeavor. Whether you’re replacing an old, worn-out bathtub or undertaking a complete bathroom makeover, the process of tub removal and replacement is a crucial step in achieving the desired aesthetic and functionality.

This intricate process involves a series of careful steps to ensure the successful extraction of the old tub and the seamless installation of the new one. From shutting off the water supply to disassembling the intricate components of the drain and overflow, each stage demands precision and attention to detail.

In this guide, we’ll walk you through the comprehensive process of removing and replacing a bathtub, offering step-by-step instructions that cover everything from preparing the area to safely disposing of the old tub.

By following these instructions, you’ll be well-equipped to transform your bathroom space into a haven of comfort and style.

Table of Contents

Shutting Off the Water

Before proceeding with tub removal, ensure to turn off the water supply. If your bathroom doesn’t feature a separate cutoff valve, you’ll need to shut off the water supply for the entire house.

To release any remaining pressure in the lines, open a valve at a lower point within your home.

Tub Drain Components

Tub drains comprise various components that must be dealt with first. For instance, a stopper may need to be unscrewed, providing access to the drain flange situated at the tub’s base.

Using a specialized tool designed for tub drain removal, unscrew the flange itself.

Handling Overflow Valve and Tub Spout

Using a screwdriver, carefully detach and remove the waste and overflow valve cover located on the tub’s side. Additionally, it’s crucial to remove the tub spout since it’s located on a part of the wall that will be removed.

Some spouts might have a set screw holding them in place, while others can be twisted off by turning counterclockwise.

Disassembling the Drain

To disconnect the drain, you’ll need access to the underside of the tub, either from behind the wall or through the ceiling beneath the bathroom.

Using Channellock pliers, disconnect the pipes below the T junction where the drain and overflow valve meet. If the fittings are galvanized steel, you might need a penetrating lubricant like PB B’laster to loosen the joints.

Once the nut connecting the drainpipe is loosened, unscrew it completely by hand and remove the entire section.

Preparing for Tub Removal

Create a space for tub removal by cutting out a section of drywall about 6 inches above the tub on all three sides. This will facilitate easier wall repair later on. Cut along the marked guideline using a drywall saw, removing the section between the line and the tub down to the studs.

This should be done on the sides of the tub as well. Once this is cleared, you’ll gain access to the screws or nails attaching the tub flange to the studs. Use a pry bar to remove these from the top and sides of the tub.

Removing the Tub

Before removing the tub, remove any trim molding from the alcove’s sides. With the assistance of a partner, lift the front edge of the tub while someone else slides one-by-four underneath it, raising it off the floor.

Carefully slide the tub out of the alcove using the one-by-four as skids. Remove any remaining stringer supports on the wall. With the alcove exposed, thoroughly clean the area and clear away any remaining debris or nails.

Disposing of the Old Tub

The method of disposing of the old tub depends on its material. Cast iron tubs need to be broken up with a sledgehammer, preferably within the bathroom for easier removal.

For other tub types, such as steel, composite, or fiberglass, they can be removed whole or cut up using a reciprocating saw. Porcelain over steel tubs should generally be disposed of as a whole unit. Check local guidelines and regulations for proper disposal methods.

Bathtub Replacement

Preparing for Installation

Prior to installation, measure the width and depth of the alcove. Most bathtubs are either 5 feet long and 30 or 32 inches wide. Note the drain’s location as well; if it’s on the left side, you’ll need a left drain tub, and if on the right, a right drain tub.

If the new tub is a different size or orientation, you might need to relocate the rough-in plumbing. Ensure the subfloor is level; if not, use a leveling compound to even it out. Protect the new tub by keeping it safely packaged until ready for installation.

Installing the New Tub

Set a section of cardboard inside the tub to protect the surface from scratches and tools. Remove the remaining cardboard packaging, inspect the tub for damage, and report any issues to the manufacturer. Attach the tub’s sound deadening and leveling pad onto the subfloor.

Carefully set the tub onto the skids with a helper and slide it into the alcove. Check for levelness and use shims if necessary. Mark a reference line on the studs as a guide. Temporarily remove the tub.

Installing Support

Install a stringer below the tub flange on the long wall. Allow for the flange’s height by measuring the distance below the reference line on each stud. Attach a two-by-four of the tub’s length to the studs at the new reference marks using deck screws.

Attaching Drain and Overflow

Follow the manufacturer’s instructions to install the drain. Apply plumber’s putty to the drain flange’s underside and attach it to the threads. Connect the overflow valve and attach the overflow pipe and drain pipe with a T-fitting.

Securing and Finishing

When the tub is repositioned, ensure the flange rests on the stringer along the back wall. Connect the pipes and secure them, aligning the flange with the reference marks established earlier. Fasten the tub flange to the studs using roofing nails.

Finish the wall with drywall and paint, reinstall baseboards and molding, reattach the spout, and your new bathtub installation is complete.