How to Build a Waterproof Shower Pan Using Composeal, Pre-Pitch and Quick Pitch
A properly built shower pan is the foundation of every successful tile shower installation. Long before tile, grout, and fixtures are installed, the shower base must be designed to direct water toward the drain while protecting the structure from moisture intrusion.
This installation guide explains how to build a traditional waterproof shower pan using Composeal Blue waterproofing membrane, the Pre-Pitch shower slope system, Quick Pitch float sticks, Kirb Perfect curb components, and an Ebbe square shower drain.
When installed correctly, these components work together to create a durable, code-compliant shower system designed to provide years of reliable performance.
Products Used in This Installation
This shower system combines several components that each perform a specific function within the completed shower assembly.
- Pre-Pitch Shower Slope System
- Quick Pitch Shower Slope System
- Kirb Perfect Shower Curb System
- Quick Clips
- Weep Hole Protector
- Universal Center Ring
- Ebbe Square Shower Drain
- Composeal Blue Waterproofing Membrane
- Composeal Flexible PVC Cement
- Composeal Curb Protectors
- Composeal Inside Corners
Together, these products help create proper drainage, waterproofing protection, and a solid foundation for tile installation.
Why a Pre-Slope Is Important
One of the most common mistakes in shower construction is installing a waterproof membrane over a flat subfloor. Water that reaches the mortar bed must have a path to the drain, even below the tile surface.
The Pre-Pitch system creates the required slope beneath the waterproofing membrane, helping direct moisture toward the drain assembly and reducing the risk of standing water within the shower base.
This hidden slope is one of the most important elements of a properly functioning shower pan.
Step 1: Verify the Subfloor Is Level
Before installing the Pre-Pitch system, inspect the subfloor to verify that it is structurally sound and reasonably level.
If significant unevenness exists, use an appropriate floor-leveling compound before proceeding. Starting with a level surface helps ensure the completed shower floor will maintain a consistent slope toward the drain.
A properly prepared subfloor provides a stable foundation for every layer that follows.
Step 2: Plan the Pre-Pitch Layout
The next step is determining how many Pre-Pitch sticks will be required based on the size and shape of the shower floor.
Each shower layout is different, and larger showers may require additional sticks or extension pieces to maintain proper support throughout the mortar bed.
Positioning should be planned before any cutting begins.
Step 3: Measure and Cut the Pre-Pitch Sticks
Once the layout has been determined, mark each Pre-Pitch stick to match the required dimensions of the shower floor.
If any wall is located more than three feet from the drain, extension pieces may be required to maintain the proper slope across the entire floor.
The sticks can be cut using PVC pipe cutters, a hacksaw, or a diamond blade suitable for plastic materials.
Step 4: Position the Pre-Pitch Around the Drain
When positioning the Pre-Pitch sticks, the narrow ends should stop approximately one-half inch from the edge of the drain flange.
This spacing helps eliminate unwanted height transitions when the upper drain flange is installed and creates a smoother surface for the mortar bed.
Proper drain preparation at this stage will make later installation steps much easier.
Step 5: Secure the Pre-Pitch System
Once all pieces have been fitted correctly, secure the Pre-Pitch system to the subfloor.
For concrete installations, double-sided tape can be used to hold the sticks in place during mortar placement. For wood subfloors, screws or nails may be used, provided they are countersunk below the surface to prevent damage to the waterproofing membrane.
After the system is secured, the shower floor is ready for the pre-slope mortar bed.
With the pre-slope complete, the next phase is preparing, cutting, and installing the Composeal Blue waterproofing membrane that protects the shower structure from moisture intrusion.
Installing the Composeal Blue Waterproofing Membrane
Once the pre-slope mortar bed has cured, the next step is installing the waterproofing membrane. The waterproofing layer is one of the most critical components of the entire shower assembly because it protects the structure from moisture penetration while directing water toward the drain system.
Composeal Blue waterproofing membrane is designed specifically for traditional shower pan construction and can be used in conjunction with standard clamping ring drains and square drain installations when proper accessories are used.
A properly installed membrane creates a durable waterproof barrier beneath the tile assembly while helping prevent leaks and water damage.
Step 6: Measure and Cut the Shower Pan Liner
Before bringing the membrane into the shower area, measure and cut the material outside the shower stall.
Measure the inside dimensions of the shower floor and add sufficient material to extend at least 9 inches up each wall. The membrane must also continue completely over the shower curb and down the outside face of the curb.
Taking time to properly measure and cut the membrane before installation helps simplify the fitting process and reduces the likelihood of installation errors.
Step 7: Joining Membrane Sections When Required
For larger shower installations, multiple sections of membrane may be required. Composeal Flexible PVC Cement allows separate pieces to be joined into a continuous waterproof liner.
Overlap adjoining sheets by approximately 2 inches and apply PVC cement to both surfaces. Allow the cement to become tacky before pressing the materials together.
Once joined, firmly roll or press the seam to ensure proper bonding.
Step 8: Position the Membrane Inside the Shower
After all required cuts and seams have been completed, carefully position the membrane inside the shower enclosure.
The membrane should extend a minimum of 3 inches above the finished height of the shower curb on all walls.
This extra height helps ensure that water remains contained within the shower system even under demanding conditions.
Step 9: Fasten the Membrane Correctly
The membrane may be attached to wood framing using roofing nails or to wood and metal framing using screws and washers.
However, fasteners must never be installed lower than 2 inches above the top of the finished shower curb.
It is equally important that the membrane is not fastened through the floor of the shower pan or through the sloped mortar bed.
Following these fastening guidelines helps preserve the integrity of the waterproofing system.
Step 10: Install Corner Folds and Curb Protection
Inside corners are typically folded into place using a traditional "dog ear" fold that can be tucked behind the framing and secured near the top edge of the membrane.
Outside corners and curb transitions require additional protection because they cannot be properly waterproofed using folds alone.
Composeal preformed corners and curb protectors are specifically designed to reinforce these vulnerable areas.
Preparing for Drain Installation and Flood Testing
After the membrane has been properly installed and all corners have been reinforced, the shower pan is ready for drain preparation and flood testing.
This stage is critical because it verifies that the waterproofing system has been installed correctly before additional construction takes place.
The next section covers drain preparation, sealing the membrane to the drain assembly, and performing a 24-hour flood test to confirm the shower pan is watertight.
Preparing the Drain Area for Waterproofing
Once the Composeal waterproofing membrane has been installed and all seams and corners have been properly secured, attention can turn to the drain assembly. This step is critical because the drain connection is one of the most important waterproofing details in the entire shower system.
Careful preparation helps ensure that water reaching the waterproofing layer is directed into the drain rather than escaping beneath the shower floor.
Step 11: Trim the Membrane Around the Drain Opening
After locating the drain opening beneath the membrane, carefully trim the waterproofing material to match the exact size of the drain opening.
Do not cut beyond the drain opening and do not enlarge the opening unnecessarily.
The bolt holes should not be cut out. Instead, they should be pierced individually using a nail, awl, or punch so that the membrane fits tightly around each bolt location.
A tight fit around the drain assembly helps improve the waterproof seal and reduces the potential for leaks.
Step 12: Seal the Membrane to the Drain Flange
Before clamping the drain assembly together, apply an even bead of sealant between the waterproofing membrane and the lower drain flange.
This seal creates an additional layer of protection at one of the most vulnerable areas of the shower pan.
After the sealant has been applied, carefully position the membrane and install the upper drain flange.
The drain assembly should then be tightened evenly to create a secure waterproof connection.
Step 13: Perform a 24-Hour Flood Test
Before covering the waterproofing system with mortar, every shower pan should be flood tested.
Insert an approved test plug into the drain and fill the shower pan with water to the top of the curb.
The water should remain in place for a minimum of 24 hours.
This test helps verify that all seams, corners, and drain connections are watertight before proceeding with the remainder of the installation.
Any loss of water should be investigated and corrected before continuing.
Planning the Quick Pitch Installation
After the shower pan has successfully passed the flood test, construction can continue with the final mortar bed using the Quick Pitch system.
The first step is determining the overall size and shape of the shower along with the drain location.
Accurate measurements help determine how many float sticks, extensions, and accessories will be required for the installation.
Measuring for Quick Pitch Components
Measure the distance from the drain to each wall, curb, and corner of the shower.
These measurements determine whether standard Quick Pitch float sticks will be sufficient or whether extension pieces will be required.
For larger shower installations, Extended Float Stick kits can be used to maintain proper slope throughout the shower floor.
Using the Universal Center Ring with Ebbe Drains
Standard Quick Pitch kits include a center ring designed for traditional shower drains. However, installations utilizing an Ebbe square shower drain require a Universal Center Ring.
The Universal Center Ring allows the Quick Pitch float sticks to integrate properly with square drain installations while maintaining consistent slope around the drain area.
This accessory is an important component whenever an Ebbe square drain is incorporated into the shower system.
Calculating Materials Before Installation
Before mixing mortar, take time to calculate the materials required for the project. This includes determining the number of Quick Pitch float sticks, Quick Clips, curb sections, and the amount of deck mud required to complete the shower floor.
Proper planning helps avoid delays and ensures all materials are available before installation begins.
Once the layout has been finalized and all components have been gathered, the shower is ready for installation of the Quick Pitch system and construction of the final mortar bed.
Installing the Quick Pitch System
After the waterproofing system has passed the flood test and all measurements have been verified, the final mortar bed can be installed using the Quick Pitch system.
The Quick Pitch center ring and float sticks are positioned around the drain to establish a consistent slope from the perimeter of the shower toward the drain opening. This helps eliminate guesswork while creating a professional-quality shower floor.
Each float stick acts as a guide during mortar placement, helping maintain the proper pitch required for efficient drainage.
Using Quick Clips for Additional Support
Quick Clips can be installed between float sticks to provide additional support when building larger shower floors or installations with complex layouts.
These clips help maintain alignment while the mortar bed is being placed and compacted.
For larger custom showers, Quick Clips can improve consistency and help create a smoother finished slope across the entire shower floor.
Installing the Final Mortar Bed
Once the Quick Pitch components have been positioned correctly, deck mud can be placed over the waterproofing membrane.
Begin by packing mortar around the perimeter of the shower and along the top edges of the Quick Pitch float sticks. Continue filling the spaces between the sticks while compacting the mortar to create a dense and stable shower floor.
Using a straightedge, screed the mortar flush with the top of the float sticks to create a smooth and consistent slope toward the drain.
Building the Shower Curb with Kirb Perfect
The shower curb is an important part of the waterproofing system and helps contain water within the shower area.
Kirb Perfect components simplify curb construction by creating a consistent form that can be filled with mortar and finished to receive tile.
Proper curb construction helps maintain waterproofing integrity while providing a durable transition between the shower and the bathroom floor.
Preparing the Shower for Tile Installation
After the mortar bed has cured, the shower floor is ready for tile installation. At this stage, the waterproofing, drainage, and slope systems have already been completed beneath the tile surface.
Proper preparation during the earlier stages helps simplify tile installation and supports long-term shower performance.
The completed shower floor should provide consistent drainage toward the drain while creating a stable foundation for tile and grout.
Benefits of a Complete Shower System
Using compatible components throughout the shower construction process helps eliminate many common installation problems.
- Proper pre-slope beneath the waterproofing membrane
- Reliable waterproofing protection
- Consistent slope toward the drain
- Simplified curb construction
- Compatibility with Ebbe square shower drains
- Professional-quality finished results
When installed correctly, the combination of Composeal waterproofing, Pre-Pitch, Quick Pitch, Kirb Perfect, and Ebbe drains creates a complete shower system designed for long-term performance and reliability.
Final Thoughts
Building a custom shower pan requires careful planning, proper waterproofing, and attention to detail. By following a proven installation process and using quality components, homeowners and contractors can create a durable shower system that provides years of dependable service.
Whether you are building a traditional tile shower, a custom shower enclosure, or a large residential or commercial installation, proper slope and waterproofing remain the keys to long-term success.
Related Resources:
- Quick Pitch Installation Guide
- Quick Pitch System Specifications
- Quick Pitch Video Library
- Ebbe Square Shower Drain FAQ
- Installing an Ebbe Drain with Quick Pitch
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