Creating a watertight space for showering is easy when you’re working in a traditional space like a large bathroom, where you can use pre-sized shower pans and liners. However, when you’re dealing with a tiny space (like a DIY camper) it can get much more tricky. In this post I will outline how I prepared our tiny bathroom space to be used as a shower.
Drill and Cut First
Before you make your space watertight, you should do any drilling or cutting required to turn the area into a functional shower and/or toilet. In our case, we wanted a “wet bath” space that had both. Be sure you’ve cut holes for the shower/toilet water supply, the drain and toilet flange, and your hot/cold knobs and shower head. I cover this in more detail in my articles on plumbing.
Make Your Surfaces Smooth
You’ll get best results if your surfaces are smooth, so be sure to sand down any rough edges. If you’ve been drilling or cutting, this could be an issue. Take some sandpaper to those holes and make sure they’re nicely finished. It wouldn’t hurt to double-check the fit of your toilet and shower parts at this point to be sure you’re ready to commit to the design and placement of everything.
Apply the Sealant
In order to use the space as a shower, you need a waterproof membrane of some sort. Most residential installations use a shower pan/liner and line the walls with sheets of waterproof material. However, in a tight space like this one, I used a paint-based alternative. It’s called RedGard, and you can likely find it at major hardware stores alongside shower tiling and grout. It’s rated for use as a waterproof shower membrane and meets residential building code. So, it’s great stuff!
I’d recommend a foam roller for this project. It will put the paint on nice and smooth, which is especially important because you’ll be doing several layers. Be sure to use painter’s tape to mask off any surfaces you don’t want a bright red color! This product goes on pink, and you’ll know it’s dry when it turns red, hence the name.
For your first layer, focus on even, consistent coverage with a slight overlap as you go. Use a smaller foam brush for corners and other tight spaces you can’t get with the roller. Leave it to dry for a couple hours. When you apply the second coat, you won’t need as much product because you’re applying on top of a finished surface. It wouldn’t be a bad idea to roll in the opposite direction (up-down vs. left-right) compared to your first coat.
If you think you have enough RedGard left for a third coat, go for it. It would provide extra protection and peace of mind. Otherwise, you can hold on to the rest and use it for repairs or future projects.
Apply Top Coats
You’ll want your new waterproof enclosure to have a nice finish, both on the floor and walls. For our project, we used a Rustoleum Tub & Shower refinishing kit. It was a 2-part epoxy that ended up glossy white and gave us two generous coats. It covered the RedGard just fine, and I used the same type of foam brush for a nice, smooth finish. Be sure to keep the area well-ventilated – this stuff really smells!
Once your epoxy is completely dry, it will be easy to keep clean and could also provide a good base for tile or other coverings for your floor or walls. I’d recommend applying the epoxy even if you’re planning on covering it up, because it will give you one more layer of protection over your RedGard membrane.
Finish It Up
Once your shower area is completely dry and you’ve removed your painter’s tape, you are ready to put in your toilet / shower components! See my articles on plumbing for more information on installing these types of fixtures in your tiny camper. Stay clean!