Building your own custom shower pan allows you to create the exact shower you want for your bathroom within your budget. With the right materials and techniques, you can build a watertight, sloped shower pan that will last for years. This comprehensive DIY guide will walk you through each step of planning, preparing, and installing a tileable shower pan from scratch.

Planning Your Shower Pan

Before you start building, take the time to map out your shower pan design. Careful planning ensures your DIY shower pan will fit the space properly and function flawlessly.

Choose a Location

Pick an appropriate location in your bathroom for the shower enclosure. Consider plumbing locations and bathroom layout when deciding where to build your shower pan.

Measure the Area

Take precise measurements of the shower pan area. Account for the thickness of the shower pan materials when planning dimensions. Record the length, width, and any unique shapes or angles.

Select a Drain Type

Choose a center drain or linear trench drain style based on your shower pan size and preferences. Larger shower pans often benefit from linear drains. Ensure your drain type complies with local plumbing codes.

Design the Slope

Shower pans require a slope for proper drainage. A 1⁄4 inch per foot slope is recommended. Calculate the required height difference from the drain to the shower threshold. Design a smooth sloped profile.

Pick Shower Pan Materials

Common options include mortar bed, hot mop, acrylic, and preformed shower pan kits. Select waterproof, durable materials that suit your project skill level and budget.

Preparing the Shower Pan Installation Area

Proper prep work ensures the shower pan has a solid base and the installation goes smoothly.

Protect the Surrounding Areas

Mask off any walls, floors, or cabinets around the shower area prior to installation. Use plastic sheeting and painters tape to shield surfaces from splashes.

Demolish Existing Structures

Remove any old shower pans, walls, tiles, or plumbing fixtures from the area. Scrape off old adhesives or mortars down to the bare subfloor.

Inspect Plumbing Locations

Confirm the drain pipe size/location and supply pipe stubs match your planned shower pan layout. Adjust as needed before installation.

Waterproof the Subfloor

Apply a waterproofing membrane like RedGard or Kerdi over the entire subfloor area. Seal seams and edges and allow to fully cure.

Build a Mortar Bed (Optional)

Constructing a sloped mortar bed can help accurately achieve the desired slope profile. Let it fully cure before installing the shower pan.

Constructing a Mortar Shower Pan

Mortar shower pans provide a custom fitted, tile-ready base for tiled showers. Advance planning is required for proper mortar pan fabrication and curing.

Establish Adequate Perimeter Support

Build temporary perimeter support boards the thickness of the planned mortar bed (usually 1-2 inches). This contains the mortar until cured.

Install the Drain

Set the drain assembly at the planned location per the manufacturer instructions. The top should be level with the subfloor.

Create Weep Holes

Drill a series of 1/4 inch weep holes surrounding the drain location in the subfloor. This allows moisture under the mortar to escape.

Build the Mortar Base

Mix and pour dry-pack sand and cement mortar. Screed to the designed profile making sure mortar contacts drain flange. Trowel smooth.

Cure the Mortar Bed

Allow mortar bed to cure fully over several days. Mist with water and keep damp using plastic sheeting while curing.

Apply Waterproofing

Install a waterproofing membrane like RedGard or Kerdi over the cured mortar bed per manufacturer specifications.

Install Cement Backerboard

Once waterproofed, screw cement backerboard into surrounding studs atop the mortar shower pan to protect the waterproofing layer.

Tile the Shower Pan

Your sloped, watertight mortar shower pan is now ready for finish surface materials like tile. Install per tile manufacturer recommendations.

Building a Prefabricated Shower Pan

Prefab shower pan kits offer an easier alternative to building a mortar shower pan from scratch. Kits come with a pre-sloped shower pan and drain assembly.

Select an Appropriate Shower Pan Kit

Choose a kit with the correct dimensions for your space. Kits typically come in neo-angle, rectangular, and square shapes.

Prepare the Alcove

Ensure the alcove area is clean, dry, and properly framed and supported. Install cement backerboard on walls.

Set and Secure the Pan

Place the prefabricated pan in position. Check it is level. Drill pilot holes and screw into studs to securely fasten.

Install the Drain

Attach drain pipes, gaskets, and fasteners per kit instructions. Tighten drain bolts evenly to avoid cracking the pan.

Test for Leaks

Plug the drain and fill pan with water. Mark water level and wait 1 hour. If water remains at the marked level, the pan passes.

Waterproof Pan Seams

Apply thinset and waterproofing tape over all seams between pan edges and walls. Apply a waterproofing membrane over pan.

Finish Walls and Pan

Once sealed, finish surrounding walls and shower pan surface with cement backerboard, tile, or other decorative materials.

Building a Liquid Applied Shower Pan

Liquid-applied shower pans like hot mop or acrylic are installed atop a substrate for convenient shower pan creation.

Prepare the Installation Area

Clean and dry the shower pan substrate. Tape off drains to prevent clogs and mask surrounding areas for overspray.

Prime the Substrate

Apply manufacturer recommended primer to the entire substrate area. This enhances bonding with the liquid waterproofing layer.

Install the Drain

Position and install the clamping ring or threaded drain assembly per specifications before applying the liquid layers.

Apply Base Layer

Pour the basecoat liquid (acrylic or hot tar) over the sloped substrate. Use a notched trowel to gauge thickness.

Embed the Reinforcing Fabric

Press the fiberglass mesh or polyester fabric into the basecoat and smooth any wrinkles or folds.

Apply Top Coat

Once basecoat has set, apply the second thicker topcoat layer and feather seams and edges.

Seal All Penetrations

Caulk drains, pipes, or corners fully with silicone caulk. Avoid gaps in the waterproof membrane.

Install Finishing Surface

Allow 24 hours to cure fully before installing tile, panels, or other shower pan finishing materials.

Common Mistakes to Avoid

Steer clear of these pitfalls when planning and constructing your custom DIY shower pan for optimal results:

  • Forgetting to waterproof floor and walls before pan installation
  • Not allowing enough slope and drainage for proper water runoff
  • Using non-waterproof materials like drywall or wood
  • Inadequately supporting the shower pan along the edges
  • Skipping leak tests before finishing surfaces are applied
  • Failing to caulk all seams, corners, and penetrations
  • Not allowing adequate curing time before using shower
  • Using adhesives or sealants not specifically designed for wet areas
  • Making pan larger than necessary, limiting surrounding support

Tips for Success

Keep these best practices in mind for a watertight and durable shower pan:

  • Fully waterproof all surfaces including floors, walls, and ceilings
  • Create 1⁄4 inch per foot slope for excellent drainage
  • Choose optimal non-porous pan materials for watertight performance
  • Follow manufacturer instructions for all products used
  • Perform thorough leak checks before finishing
  • Ensure adequate perimeter support around entire pan
  • Allow sufficient curing time based on materials used
  • Clean pan regularly to prevent damaging soap scum buildup
  • Use mold-resistant sealants and caulking appropriate for wet areas
  • Install expansive wall tiles on cement backerboard, not directly on pan

Frequently Asked Questions

Get answers to some common DIY shower pan installation questions:

What shower pan materials are best?

Mortar, hot mop, and acrylic are top choices for durability and waterproofing. Mortar requires the most skill while pre-sloped pans are easiest.

How do I create a slope for drainage?

Use a mortar bed, pre-sloped foam pans, or self-leveling underlayment to create 1⁄4 inch per foot slope pitched toward the drain.

Can I install a vinyl or fiberglass pan?

Yes, these affordable options can be installed like acrylic or hot mop pans atop a substrate. Cut panels to fit the space before adhering.

What can I use to waterproof my pan?

RedGard, Kerdi, and Laticrete Hydroban are popular waterproofing membranes that create watertight shower pans.

How long does a mortar shower pan take to cure?

Mortar shower pans require 2-3 days minimum to fully cure and dry before applying finishes.

Should I do a water test before tiling?

Yes, it’s crucial to flood test your pan and allow it to sit overnight before continuing with tile or other finishing layers.

How do I clean and maintain a shower pan?

Use non-abrasive bathroom cleaners and avoid letting soap scum buildup. Avoid using harsh chemicals or leaving standing water.


Constructing your own shower pan allows complete control over the size, layout, and finish material selections. While advanced DIY skills are needed for mortar and hot mop pans, prefab pan kits offer an easier option with less installation work. Whichever method you choose, be sure to thoroughly plan dimensions, slope, and drain location while waterproofing all surfaces for a successful watertight DIY shower pan that will provide enjoyment for years to come.