How Thick Should A Concrete Shower Base Be?

Are you remodeling your bathroom shower and need help finding the proper dimensions to follow? If so, you've come to the right place. We've done the research to provide you with this handy guide that will provide you with all the information you need to properly install a concrete shower base.

Pre-made shower pans will have instructions detailing how thick the mortar beneath should be. If you plan to install tile, your base will need to be 2-3-inches thick at the edge and slightly smaller at the drain to account for slope.

You're probably wondering if there are any other differences between using a pre-made shower pan versus concrete. And what kind of concrete do you need for a shower base? To learn all about installing a shower, keep reading.

A porcelain shower base in a bathroom, How Thick Should A Concrete Shower Base Be?

What Kind of Concrete Do You Use For a Shower Base?

The best concrete to use for a shower base will consist of a mix between Portland cement and fine sand. You can mix your own or purchase a pre-mixed shower or floor-specific concrete product. Either option will leave you with a good end result, but mixing your own takes a little more time and requires you to measure out the ingredients correctly. 

This concrete mix works well for showers; it's available in a 40-pound bag. Click here to see it on Amazon.

Pre-made Shower Pans

The pre-formed shower pans available for purchase through major retailers are usually easier and less costly to install. They come pre-graded for drainage, taking out some of the more complicated work for do-it-yourselfers.

These shower pans also offer the ability to shorten the project completion time compared to mud bed showers, which require additional dry time.

Tile Redi Shower Base

This pre-made shower base can be tiled to match, creating the perfect look for your bathroom. Click here to see it on Amazon.

Mud Bed Showers

Mud bed showers, or shower bases formed from concrete, are more complicated to install because the measurement needs to be exact, including the slope. This can be difficult for the average homeowner to perfect on their first try and should be done by a professional.

Mud bed showers allow for more customization than pre-made shower pans since they can be molded into different shapes and sizes.

SimpleSet Thin-Set Mortar


This mortar is another good option for concrete shower base installation. Click here to check it out on Amazon.

What Do You Put Under a Shower Base?

Large sized bathroom with acrylic shower base, 6 Simple Steps To Clean An Acrylic Shower Base

Shower bases need to be set onto a layer of mortar to provide an even surface to support the base and people's weight using the shower. Installing a shower base on an uneven surface could result in the base cracking as it flexes under the weight of its user.

Pre-made shower bases will include directions on how to lay the mortar properly. For more information on this topic, read our post "What Do You Put Under A Shower Base?" 

Do You Waterproof Under a Shower Base?

Yes, you should always waterproof the floor beneath a shower base, even when using pre-molded bases. Mortar is technically waterproof. However, it is a porous material that will allow moisture to seep through to the subfloor if it escapes the shower base. Because of this, you need to take steps to protect the subfloor beneath the mortar.

Oatey Shower Pan Liner Kit

This liner kit will be perfect for your project. Click here to take a look at it on Amazon.

How Do You Waterproof a Shower Base?

To properly waterproof the floor below your shower base, you need to install a shower pan liner or a waterproof membrane product. Shower pan liners are the most commonly used waterproofing material for the subfloor beneath the shower mortar.

It is applied both underneath and on top of the liner. Some products can be painted onto the floor to create a waterproof membrane too.

Custom Building Products RedGard Waterproofing Membrane

This waterproofing membrane is rolled onto the floor like paint to create a moisture barrier. Click here to see it on Amazon.

How To Build a Concrete Shower Base?

Installing a concrete shower base needs to be exact, so if you aren't confident in your own craftsmanship, it's best to hire a professional. Before you begin on the shower base, your plumbing and shower framing need to be in place.

Here's a quick step-by-step overview of the process and a video to help you along:

  1. Install new subfloor and lower portion of the drain, if necessary.
  2. Frame in the shower curb using concrete bricks or lumber stacked to your desired curb height. 
  3. Lay down asphalt felt in the shower area to provide a textured surface for the mortar to stick to.
  4. Install lathe over the shower area, wrap it around the curb on both sides, and secure it with nails.
  5. Lay the first layer of mortar down and allow it to cure for at least 8 hours.
  6. Lay down your shower pan liner, secure it with tape, and cut a hole for the drain and seal it, then trim the excess liner.
  7. Finish installing the drain.
  8. Install cement backer boards on the walls.
  9. Apply the second layer of mortar.


Can You Put Tile Directly on Concrete?

Yes, you can install tile directly on your concrete shower base. However, it's not the most durable way to lay your tile. If the concrete shifts or cracks, the damage will transfer directly to your tiles, leaving visible cracks and damage. Tile-ready shower pans or uncoupling membranes are both more effective and convenient ways to install tile in your shower.

What is an Uncoupling Membrane?

Uncoupling membrane is a thin layer that you can apply over a surface, like concrete, to adhere tiles to. Since the membrane creates a layer between the tile and the concrete, it won't flex and move when the concrete does, preventing the tile from cracking.

It will also make your next bathroom remodel a breeze, allowing you to remove the tile much more easily than if they were applied directly to the concrete.

Snap Products Store Uncoupling Membrane

This uncoupling membrane comes in a roll that covers 108 square feet, which is plenty for most shower projects. Click here to see it on Amazon.

Can You Repair Cracks in Concrete Shower Bases?

It is possible to repair cracks in concrete shower bases, but it may be best to consider a full replacement depending on the extent of the damage. If the crack has allowed water to soak into the subfloor due to a hole in the liner, you need to replace the entire base.

If you caught the crack quickly and there doesn't appear to be any water damage or mold, you can apply a cement patch product to the crack to fill it in before any serious damage occurs.

This concrete patch formula should work well for small cracks in your shower, but give it ample time to dry before you resume using it. Click here to see it on Amazon.

Can You Paint a Concrete Shower Base?

If you are trying to make the most out of your existing concrete shower base, there are ways to improve it without a complete replacement. For a quicker, more cost-effective makeover, you can use epoxy paint, or if your shower has tiles pull them up and replace them.

Replacing the showerhead and faucets is another good way to update your shower without a hefty price tag. Try changing the finish for a whole new look.

This epoxy paint formula will work great on concrete shower bases, and it's available in two colors. Click here to see it on Amazon.

Wash Your Worries Down The Drain 

Now that you know all the basics of installing a shower base, you're ready to tackle your next project. Start by figuring out what type of shower base you want, and go from there. Do you want tiles on the shower floor or a simple pre-made base? Remember to measure carefully, and don't forget to have fun with your remodel.

For more help designing the details of your shower makeover, you can read our article "How High Should Grab Bars Be Installed In A Shower?"

If you need more guidance on the best materials to use for a shower remodel, take the time to read our article "Is Epoxy Grout Good For Showers?"


  1. Do not paint your showers with regular paint. I have a night are with the house i bought from the previous owner. We put tile in and it turned out great!

  2. Thickness depends on what is being placed upon the floor. The heavier the object, the thicker the concrete needs to be! There is some very useful information in this article. Thanks guys!

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