Outdoor showers are great after a day at the beach or even rinsing off around the pool. But, since they’re typically close to the house, it’s important that they drain well to prevent pudding and foundation damage. When a young couple decided to install an outdoor shower in their backyard, landscape contractor Jenn Nawada and mason Mark McCullough pitched in with a drainage solution.
How to Install Drainage for an Outdoor Shower
There are two options for outdoor shower drainage: A drywell or an underground drainage pipe. In our case, the yard was sloped nicely away from the house, making it a great candidate for underground drainage. Note that the pipe can terminate to a patch of dry gravel or into a drywell, depending on the slope and the homeowner’s preference.
- Call 811 to have your underground utilities marked. It’s a free service that significantly increases your chance of a safe dig.
- Mark the ground with marking paint to create a path to follow with shovels or an excavator. The drainage pipe should run as far from the home, pathways, and outdoor living spaces as possible, and take advantage of any downhill slope available.
- Using a shovel, dig around the foundation in the area of the outdoor shower. With the foundation exposed, apply a layer of waterproof ice and water shield membrane to the foundation.
- Continue digging the trench (this time with a shovel or excavator), approximately two feet wide and 18 inches deep.
- Apply a layer of crushed stone to the base of the trench, approximately 6 inches deep.
- Wrap the perforated pipe with non-woven geotextile fabric and zip-tie the fabric to the pipe. This will keep debris out of the pipe while allowing water to flow through. Lay it in the trench, starting directly below the outdoor shower’s location. Ensure that it is pitched away from the house by placing a level on the pipe in several areas, with only a 1/4-bubble visible between the lines.
- Place a layer of crushed stone over the entire pipe, covering the pipe by around 2 inches.
- Install a layer of landscape fabric on top of the crushed stone and cover it with the removed dirt.
- Apply a grass seed over the backfilled trench and water it in the mornings or evenings. The grass seed should take 7 to 14 days to germinate.
- Install pavers in the patio space for comfortable footing and effective drainage.
Resources
When installing an outdoor shower, it’s important to have proper drainage, especially when it is close to a house. Mark chose not to install a dry well tank because the homeowners had so much land to distribute the water into. He chose to run a pipe at a slanted pitch away from the house and straight into the yard with some crushed stone at the end.
Use spray paint for the outline of where the shower enclosure and drain pipe will go. The end of this drain pipe was placed about 30 feet away from the house. Call 811 before you start digging. Use shovels to start digging the areas. Carefully cutting out grass if you would like to replant it later. For faster results, rent an excavator but switch to shovels when digging next to the house. Dig to about 18 inches all around. This trench was about 30 inches wide. This trench was being dug on land that naturally sloped down, so Mark was able to taper up towards the bottom without losing a downward pitch. Otherwise, the pitch can be made with the gravel. Ice & water shield was added to the exposed foundation for a little extra water protection. It was having trouble sticking in the cold weather, so flashing tape was added.
Add gravel to the trench. Use wheelbarrows and shovels to spread out the crushed stone. 3 tons of gravel was used for this project. The shower enclosure was filled with about 10 inches of gravel. The trench with the gravel should maintain a downward slope for gravity to bring the water to the outlet. Adjust the level of the pipe so that the bubble reads about ¼ high. Add more gravel where necessary. The end of the pipe can come out to a patch of gravel like this project, or a dry well can be installed.
Cut and wrap drainage trench wrap non-woven geotextile fabric around a 4 in. perforated pipe using large zip ties to secure fabric in place. Rake over gravel with a shovel to create a dented path for the pipe. Place the pipe in the trench. Cover with a thin layer of gravel–leaving the two ends uncovered. Take landscape fabric and cover the length of the pipe. Cover with the old soil. Cover with grass seeds, the old grass, or sod.
Materials
- Ice and water shield membrane
- Flashing tape
- Crushed stone
- Perforated drain pipe
- Non-woven geotextile fabric
- Zip ties
Tools
Most homeowners will only install one outdoor shower on their house. It makes sense to rent an excavator instead of buying one.
