How to Waterproof a Shower with Schluter Membrane

How to Waterproof a Shower with Schluter Membrane

The Best Way to Waterproof a Shower

With Americans spending more and more time showering, the volume of water hitting shower walls and floors is growing exponentially. All that water eventually works itself into your bathroom's structure if your shower isn't waterproofed correctly.  

Knowing how to waterproof a shower properly can save you from leaks, mold growth, and expensive structural damage. Although waterproofing and tiling a shower used to be a tedious process, that is no longer the case with Schluter waterproofing membrane, which will help you get your new shower done faster and easier than anything else on the market. 


Why Use Schluter Waterproofing?

Schluter Shower KitTraditionally, waterproofing and tiling a shower involved sloping a dry pack mortar bed to the drain holes, covering it with a pan liner, and adding yet another mortar bed on top of that for load distribution and tile bonding. The installer would then need to waterproof the walls, typically with a liquid membrane spread across the surface. Finally, he could lay the tile.  

Unfortunately, a lack of consistent building code standards for waterproofing meant that critical steps were frequently ignored. For example, many times installers wouldn't add a slope to the dry pack mortar bed, resulting in poor water drainage.  

In other instances, non-waterproof materials were used as backerboard fasteners and shower benches, leading to leaks and mold damage. Finally, liquid waterproofing membrane, although cheap, was difficult to apply evenly across the shower surface, leading to quicker breakdown and leaks. 

Schluter is the best way to waterproof a shower because it eliminates these risks and extra steps, providing a sheet membrane that can quickly and evenly be applied to drywall or green board and make waterproofing and tiling a shower easier than ever. 


How Does Schluter Work?

Schluter gets your shower 100% ready for tiling with a wealth of products that fit your application. 

Schluter KERDI Waterproofing MembraneWhen you want to waterproof shower walls and already have drywall or cement board installed, apply Schluter KERDI waterproofing membrane directly onto the surface using inexpensive unmodified thin-set mortar for a completely sealed enclosure behind the tiles. Use KERDI-BAND waterproofing strips to seal all seams and pipe connections. 

When you want to waterproof a shower but don't have a backerboard installed, you can apply 1/2-inch thick KERDI-BOARD water-proof wall panels directly to wall studs and KERDI band to the joints, reducing the entire waterproofing process to one step.  

If you are creating a walk-in shower for safety and ease-of-access, Schluter makes the KERDI sloped shower tray, which will waterproof your floor and ensure proper drainage. These shower floor trays are available in a variety of sizes and configurations.  

Other Schluter waterproofing products include: 

KERDI-KERECK pre-formed corners that save the hassle of manually waterproofing corners. 

KERDI-SEAL pipe seal and KERDI-SEAL mixing valve seal that seal pipe protrusions and protect moisture-sensitive solid backing panels. 

KERDI-BOARD shower curb. 

KERDI-DRAIN integrated bonding flange that connects to the KERDI water-proofing membrane on the shower tray. 


How to Choose the Right Schluter Components 

The laundry list of Schluter products may seem confusing at first, but it really comes down to choosing the right components for the shower base and walls. 

To choose the right Schluter waterproof shower base: 

  1. Measure the length and width of your shower base and locate the drain. 
  2. Choose a shower tray to fit the size you measured. 
  3. Add waterproof curbs and ramps as needed 

To waterproof your shower walls with Schluter: 

  1. Calculate the total area of your walls to figure out how much coverage you need. 
  2. If you are using backerboard, buy the right amount of KERDI membrane to cover the measured area. For installations directly on the wall studs, buy the right amount of KERDI-BOARD. 
  3. Measure your seams and get the right amount of KERDI-BAND to cover them. 
  4. To easily waterproof corners, choose KERDI-KERECK. 
  5. Use KERDI-SEAL products to seal gaps from your pipes and mixing valve. 
  6. Select KERDI-DRAIN for your shower drain. 

It's that simple, but you can always contact our team for assistance selecting the right products.


Schluter Installation Tips 

We recommend hiring a professional to install your Schluter shower. If you do decide to undertake the project yourself, there are a few points to keep in mind.  

  • You must use either unmodified thin-set mortar or Schluter brand thin-set mortar to bond the KERDI membrane to the shower walls and install the shower tray. Using modified mortars may result in poor bonding. 
  • Mix the mortar to a fairly fluid consistency, but make sure it can still hold a notch. 
  • When installing the KERDI membrane, apply the mortar to the board using a 1/4-inch x 3/16-inch V-notched trowel. When installing the shower tray, use a 1/4-inch x 3/8-inch square of U-notched trowel. 
  • During bonding, periodically check behind the membrane for coverage. You want full mortar coverage to ensure proper bonding to the wall. 
  • Overlap the membrane by 2-inches on joints to ensure waterproofing integrity or use KERDI Band. 
  • When installing KERDI-BAND on corners and edges, you can crease it prior to installation to avoid the hassle of creasing it while applying mortar. 
  • Conduct a water leak test on the Schluter base installation 24 hours after setting the waterproof membrane. 

Watch the Schluter Installation video below for clear, concise instructions on waterproofing your shower. 


Schluter DITRA for Bathroom Floors 

Although waterproofing your bathroom floor isn't mandatory, it can be useful in those instances when the toilet overflows or your kid does a cannon ball jump into a filled bathtub.  

The easiest way to accomplish this is by using Schluter DITRA mats. DITRA is a polyethylene uncoupling membrane mat. It's called "uncoupling" because, when installed properly, it "uncouples" or separates your bathroom floor tiles from the substrate below. 

This is great for two reasons: 

  1. It provides an even and load bearing base upon which to install ceramic or stone tile. 
  2. If there is ever a crack in the concrete (HINT: There will be), it won't transfer up to the tile thanks to the DITRA uncoupling membrane.  

Although crack prevention and easier floor tile installation are its main benefits, DITRA is waterproof. As long as you also waterproof the seams between the DITRA mats using KERDI-band strips, you won't ever have to worry about leaks in your floor.  


The Best Way to Waterproof a Shower 

Schluter waterproofing membrane is the fastest and easiest path to a new shower that is 100% waterproofed and worry-free.  

Whether you're building a walk-in shower, shower stall, or redoing your bathroom floor, Schluter has the right product. Once you lay the waterproofing membrane, you can start laying tile and be showering before you know it. 


NEXT: Shop Schluter Waterproofing Products 

Ken, the eComfort Product Expert
Product Expert
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