How to build a drain for an outdoor shower?

Building a drain for an outdoor shower is an important step in creating a functional and aesthetically pleasing outdoor bathing area. A proper drain will allow water to flow away from the shower area, preventing flooding and slip hazards. Constructing the drain correctly is vital to ensure it lasts for years to come.

Things to Consider Before Building an Outdoor Shower Drain

When planning to build a drain for an outdoor shower, there are several things that need to be considered:

• Location – The drain needs to be positioned in an area where water will easily flow away from the shower space. Avoid low points where water can pool.
• Drainage – Make sure the drainage path leads water away from the house foundation and into a grassy area, garden bed, or storm drain system.
• Slope – The drain and drainage path should have a proper slope to keep water moving. A 2% slope is commonly recommended.
• Drain type -Select a drain style such as channel, trench, or point drain based on your shower design.
• Materials – Choose durable materials like gravel, concrete, PVC or steel that can withstand outdoor exposure.
• Freeze protection – In cold climates, precautions need to be taken to prevent the drain from freezing in winter.
• Local codes – Research local plumbing and building codes for outdoor shower and drainage requirements.

Taking these factors into account will help plan out an effective drainage system before constructing the shower foundation and walls.

Choosing a Drain Type

There are several types of drains that can be used for an outdoor shower application:

Channel Drain

A channel drain consists of a long, narrow drainage channel that is laid on a slope. The top is covered with a grate to prevent large debris from entering. Channel drains are a popular choice for outdoor showers because they can collect water along the entire length of the shower floor.

Trench Drain

As the name implies, a trench drain involves digging a trench filled with gravel that contains a perforated pipe for water drainage. The top of the trench is also covered in a grate. Trench drains work well for showers with concrete or tile flooring.

Point Drain

A point drain uses a small grate over a single drainage point. This type of drain is placed at the shower’s low point and is best suited for smaller shower stalls.

The drain type will depend on factors like the size and layout of your shower. Consult with a contractor to determine which is best for your specific design.

Outdoor Shower Drain Materials

Proper materials are needed to create a durable, long-lasting outdoor shower drain. Here are some of the most common options:

PVC

PVC is a lightweight plastic piping commonly used for plumbing drains. It is easy to cut and join with cement. PVC withstands exposure to sun, water and chemicals well. For drainage pipes, opt for rigid Schedule 40 PVC over thinner wall thicknesses.

Concrete

Concrete makes a robust drain pan or trench that won’t degrade from water exposure over time. Pre-formed concrete drainage channels are also available. Make sure to use concrete with waterproofing additives or apply a sealer for improved durability.

Gravel

A gravel trench of crushed stone makes an inexpensive sub-base layer for drainage. Fill around perforated PVC pipes with gravel, topping with landscape fabric to prevent dirt from filtering in.

Steel

Stainless steel is one of the strongest metals and is highly resistant to rust and corrosion. Steel drains and grates hold up well to constant water flow and foot traffic. Choose steel with a high chromium content for optimal weather resistance.

Pairing complementary materials for the drain parts and pipes will lead to the best performance.

How to Install a Channel Drain

Installing a channel drain is one of the more involved outdoor shower drainage methods, but creates a neat, contained look. Follow these main steps:

1. Dig a trench at least 6 inches below shower floor level, with a 2% slope for drainage.
2. Fill the trench with a 4 inch gravel base, compacting firmly.
3. Lay perforated PVC pipe in the gravel to direct water away from the shower area.
4. Place the channel drain on top of the gravel bed, ensuring it is level. The drain should have a built-in slope.
5. Cement the channel securely in place.
6. Connect unperforated PVC pipes to the drain openings, routing water away from the foundation.
7. Build the shower floor using concrete, bricks, pavers or other material, keeping the drain openings accessible.
8. Finish by inserting grates over the channel drain openings.

The drain system should be pressure tested for leaks and proper drainage prior to finishing the shower walls and plumbing.

How to Create a Simple Gravel Trench Drain

For a basic gravel trench drain:

1. Mark the drain location at shower floor low point.
2. Dig a trench approximately 12 inches wide and 8 inches deep with a slope.
3. Line the trench walls with landscape fabric to prevent soil ingress.
4. Fill the trench with 2 inches of gravel.
5. Place perforated PVC pipe in the gravel, sloped to drain away.
6. Top with more gravel until level with shower floor.
7. Finish by adding grate or cover flush with floor level.

The fabric and gravel matrix acts as a filtering system while allowing water to percolate into the drainage pipe. This is a simple, inexpensive drain option.

How to Install a Point Drain

For smaller showers, a point drain may suffice:

1. Determine the exact shower floor low point and mark for drain placement.
2. Bore a hole approximately 12 inches deep and 8 inches wide.
3. Fill bottom with gravel and top with sand for leveling.
4. Insert prefabricated point drain base into the hole.
5. Use PVC cement to attach a drainage pipe, sloped downhill.
6. Connect unperforated pipe to take water away from site.
7. Build the shower floor, keeping the drain base exposed.
8. Finish by attaching the drain grate to the base.

Point drains have a simple installation but require precise placement within the shower floor for proper drainage.

Outdoor Shower Drain Installation Tips

Here are some helpful tips to get the best results from your outdoor shower drain project:

• Always slope drainage components like pipes, gravel beds, and concrete channels toward the discharge area.
• Follow local building codes for outdoor drainage.
• In freezing climates, ensure drainage pipes are below frost line.
• Wrap or insulate water lines and drains to prevent freezing.
• Consider using a drain with built-in odor and pest control.
• Choose drain grates with small openings that won’t clog with debris easily.
• Inspect and clean drains periodically to ensure proper operation.
• Use hair catchers if draining shower directly, to prevent clogs.
• Water test for leaks and make any needed repairs before finishing shower.

A well-planned drainage system is the key to a fully functional and long-lasting outdoor shower area.

Conclusion

Installing proper drainage is one of the most important aspects of building an outdoor shower. With the right materials, slope, and drain type selected, water can be efficiently carried away from the shower space. Always consult local building codes when constructing an outdoor drain system. A channel, trench, or point drain with durable construction will withstand constant exposure to moisture. By following sound installation techniques and tips, you can create an outdoor shower drain that will work reliably for years of bathing enjoyment.