How to Replace a Bathroom Shell

Remove the handles, spout, decorative items and accessories out of the shower area. If needed, use a silicone-caulk remover to help dissolve the seals created by silicone adhesives.

Remove the old bathroom shell. Depending on the condition of the shell and the strength of the adhesive, you may be able to simply pull the shell away from the wall after you remove the caulking that lined the edges. Otherwise, use a putty knife to gently separate the shell from the wall. Use the silicone-caulk remover in tough spots, so you don't cause accidental damage to the walls.

Repair damaged walls. Repairs can range from making patches to replacing a large section of the wall, depending on the extent and type of damage. If you do notice water or mold damage, consult with a restoration service and remediate the damage before you install the shell.

Use a household-bleach cleaner to clean the space between the wall and the tub. Wear rubber gloves as you do this. If you find mold on any caulking, remove it. If necessary, re-caulk the joints in the tub.

Place the old bathroom shell over the template that comes with the new shell. Use the old shell to trace the location of items that will stick out through the shell, like the bathtub spout, handles and showerhead. If the new shell is not already cut to size, outline the dimensions of the old bathroom shell onto the template.

Trace the template onto the bathroom shell, and verify all the measurements and the locations of protruding objects are accurate.

Cut the holes for the spout, handles and other items you indicated on the template into the shell, using a jigsaw. If necessary, cut the panels of the shell to size.

Hold the cut panels of the shell up to the walls surrounding your tub. Use a pencil to indicate the location of the tops and sides of the panels, verifying you're holding the panels straight, with the help of a level.

Apply the adhesive recommended by the manufacturer, following the instructions provided.

Place the panels of the bathroom shell on the walls, per the manufacturer’s instructions, and allow the adhesive to completely dry.

Reattach the hardware you previously removed, like the spout. Then reseal all the joints with a waterproof-silicone adhesive. Allow the adhesive to dry before using the shower.