Brian Vanden Brink
Examine the conditions.
Natural elements can do a number on an outdoor shower, so look for fixtures that will stand up to salt, sand, and sun. Use mildew- and rot-resistant materials, such as pressure-treated lumber or synthetic decking, and carefully seal the area where the shower joins house walls. If temperatures in your area drop below freezing, prepare for the off-season by closing supply lines to the shower and draining water in the pipes.
Evaluate the function.
Is your outdoor shower for bathing sandy kids or for full-fledged relaxation? If all you want is a quick rinse, you can get away with the barest of plumbing, but if you want to bring the conveniences of the indoors out, you'll have a bigger project on your hands. Consider upgrading your hot-water system if guests linger under the spray. And get serious about privacy: If you're planning romantic showers under the stars, build a door.
Design the drain.
When you build over sandy soil, you may need only an opening in the pressure-treated flooring, but soils that drain slowly will require more elaborate systems, such as a French drain, which directs water underground into drain fields or dry wells. Soap and shampoo residue can clog drainage systems, in addition to threatening the natural vegetation, so use eco-friendly products.
Remember the plumbing.
If you're constructing a new home, run plumbing in the wall that the outdoor shower shares with the house. But if you have to retrofit a shower, consider hiding exposed pipes behind a wall built for this purpose.
Get the Outside Scoop.
Pick up a copy of Ethan Fierro's The Outdoor Shower: Creative Design Ideas for Backyard Living, from the Functional to the Fantastic (Storey, 2006).