How to Install a Shower Pan in Your Bathroom

By
Aaron Stickley
Aaron Stickley

Aaron Stickley is a licensed plumber with 15 years of experience in commercial, new residential plumbing, and residential service and repair. He started his own residential service and repair plumbing business. Aaron's articles about plumbing on The Spruce span four years.

Learn more about The Spruce's Editorial Process
Updated on 05/04/22
Reviewed by
Johnathan Brewer
Johnathan Brewer
Reviewed by Johnathan Brewer
Johnathan C. Brewer II is a licensed general contractor specializing in kitchen, bath remodels, and general construction with two decades of professional experience.
Learn more about The Spruce's Review Board
Installed shower base with building materials on top

The Spruce / Kevin Norris

Project Overview
  • Total Time: 1 day
  • Skill Level: Advanced

During a bathroom remodeling project, installing a new preformed shower pan is a common task. And it might be easier than you think to learn how to install a shower pan, depending on your skill level. As is true of buying a bathtub, you'll need to find a shower pan that will fit your space and work with the existing drain line. For example, if you are taking out a tub that has the drain on the right side, buy a shower pan that also has a right-side drain to avoid adjusting plumbing.

Also, if you are installing a shower as a replacement to a bathtub, keep in mind that the ideal drain size for a shower is 2-inch pipe while most tubs are plumbed with 1 1/2-inch drains. Unlike a bathtub, which can hold much more water, a shower can be susceptible to overflowing if plumbed with 1 1/2-inch pipe. So in this case, you will need to make some plumbing adjustments to increase the size of the drain. One option is to bring a new 2-inch line over from the toilet drain line or the main drain line. Once you have that sorted out, you can get on to installing your shower pan.

Tip

Installing a shower pan is a project best left in the hands of a professional to ensure a quality installation.

What You'll Need

Equipment / Tools

  • Measuring tape
  • Pencil
  • Level
  • Cardboard
  • Drill

Materials

  • Shower pan and drain fitting kit
  • Shims
  • Plumber's putty
  • Thin plastic
  • Mortar, water, bucket, and trowel
  • Screws with large heads (optional)

Instructions

Materials and tools to install a shower pan

The Spruce / Kevin Norris

  1. Measure

    Carefully measure the location for the new shower to get the correct size for the shower pan.

    Shower pan location measured out with yellow measuring tape

    The Spruce / Kevin Norris

  2. Prepare the Space

    Clean out the space for the shower pan. The walls need to be clear down to the studs. And the floor needs to be as clean as possible, so you can level the pan.

    Shower pan location cleaned with vacuum hose to prepare space

    The Spruce / Kevin Norris

  3. Dry-Fit the Shower Pan

    Set the shower pan into place to gauge any changes you might need to make to the drain. Take measurements from the walls, so you can line up the drain.

    With the shower pan in position, check along its edge to make sure it is sitting level. Use shims and make reference marks on the studs to make it easy to level the pan when you put it back in. Also, put some cardboard in the shower pan, and walk around on it to see how stable the pan is.

    Shower pan laid down and measured from wall studs

    The Spruce / Kevin Norris

  4. Attach the Drain Fitting to the Shower Pan

    Remove the pan, and install the shower drain fitting into the opening in the shower pan. Apply plumber's putty to the bottom of the flange on the drain fitting before installing it. Screw the drain fitting onto the pan, and make sure it is tight. In most cases, there is a large retaining nut that threads onto the tailpiece of the drain fitting that you tighten to secure the fitting. Make sure to install whichever gaskets or washers that are included with the drain kit.

    Depending on which shower drain you get, the 2-inch drain line might be designed to be glued onto the shower pan drain fitting. However, in most installations, a compression-style drain is the easiest to install because you can set the shower pan over the drain and then tighten the drain tailpiece onto the drain pipe with a rubber washer and nut.

    Drain fittings attached to bottom with shower pan opening

    The Spruce / Kevin Norris

  5. Recheck and Make Drain Adjustments

    Make sure the drain and shower pan line up nice and straight. Make any alignment adjustments necessary, and remove the pan again.

    Drain pipe and shower pan opening checked for alignment

    The Spruce / Kevin Norris

  6. Lay the Mortar Base

    Mix a bag of mortar, and spread it over the area where the shower pan will sit. The mortar should be about 1 inch thick. Stay away from the edges by a few inches to make cleanup easier. The fins on the bottom of the shower pan will embed in the mortar, creating a very rigid shower floor that won't flex when you walk on it. 

    Mortar spread across plywood floor to create shower pan base

    The Spruce / Kevin Norris

  7. Set and Anchor the Pan

    Set the shower pan onto the mortar, and level it carefully. Tighten the drain into place on the drain line.

    Some shower pans come with screws and brackets to attach the pan to the wall studs. Otherwise, you can use screws with large heads (such as roofing nails) to attach the flanges on the shower pan to the wall studs. Let the shower pan sit overnight for the mortar to set up before stepping into it.

    Yellow level placed on top of shower pan before anchoring

    The Spruce / Kevin Norris

  8. Check for Leaks

    Test the drain by pouring water into the shower pan. If you have access to the space below the shower, observe it from beneath the floor to check for leaks. 

    Now, you are ready to install the wall surfaces, faucet valve, and showerhead. A good solution for shower walls is a surround kit. 

    Water poured from red bucket down shower pan drain

    The Spruce / Kevin Norris