Convert Your Tub Space Into a Shower — Waterproofing and Drainage
Step 4 in swapping your tub for a sleek new shower: Pick your waterproofing materials and drain, and don't forget to test
Once you have your layout planned, fixtures chosen and tile and grout picked for your new shower, you can start planning its construction — the bones of the job. There are a lot of ways to build a shower. Which one is right for your new bathroom?
Of course, local planning guidelines will play a huge role in this. Do your homework: Call your local planning office and see what the requirements are for building a shower in your town. Don't stop there, though. Look up the Tile Council of North America's or Terrazzo Tile and Marble Association of Canada's guidelines for shower planning.
Of course, local planning guidelines will play a huge role in this. Do your homework: Call your local planning office and see what the requirements are for building a shower in your town. Don't stop there, though. Look up the Tile Council of North America's or Terrazzo Tile and Marble Association of Canada's guidelines for shower planning.
Standard rubber lining. Most showers start with a basic three-piece clamping drain and a rubber liner. This system allows the shower inspection to happen right away — before the framing is even finished, before drywall, before insulation, before low voltage and before windows sometimes.
The water in the top right corner means that the liner did not drain completely at first. Luckily, this tile crew checked it with a flood test and had it repaired.
Tip: Make sure all the water from the flood test drains away. You do not want to start tile prep over a liner installed like this. A true tile pro will double check this before the tile prep happens, as the contractors building this shower did.
The water in the top right corner means that the liner did not drain completely at first. Luckily, this tile crew checked it with a flood test and had it repaired.
Tip: Make sure all the water from the flood test drains away. You do not want to start tile prep over a liner installed like this. A true tile pro will double check this before the tile prep happens, as the contractors building this shower did.
Hot mopped waterproofing. If you live in California, you've probably seen a hot mopped shower floor (the black waterproofing in the lower portion on this picture), which is fairly common there. In this photo you can also see some reinforcing wire in place over the walls for a screed coat (concrete fill) or mud float (concrete prep for tile).
Technically, this isn't much different from a rubber liner, but a hot mop pro will have a preslope (a 1/4-inch-per-foot slope below the waterproofing) so the shower will drain fully after the flood test. Since they are prepared onsite, hot mops also follow contours better than sheet membranes.
Technically, this isn't much different from a rubber liner, but a hot mop pro will have a preslope (a 1/4-inch-per-foot slope below the waterproofing) so the shower will drain fully after the flood test. Since they are prepared onsite, hot mops also follow contours better than sheet membranes.
Screeded or floated walls. Here you can see another step in a screeded or floated wall, which is also very common in California bathrooms. This is a dying art in other parts of the world; however, there are still many tile masters (like Tarkus Tile, who did the work shown) who practice this. The pro uses a screed — a flat strip of wood, metal or plastic — as a straightedge to painstakingly level the mortar coat on a wall. The screed boards are removed during the process and filled with more mortar, leaving a perfect wall. Walls like this can be prepared perfectly flat, plumb and square.
For others (including myself), tile backer boards are a safer option to getting shower walls up and ready for waterproofing. As with waterproofing membranes, there are many backer boards to choose from. Concrete board tends to be the best.
For others (including myself), tile backer boards are a safer option to getting shower walls up and ready for waterproofing. As with waterproofing membranes, there are many backer boards to choose from. Concrete board tends to be the best.
Waterproofing colors. Waterproofing products come in many colors and styles. The one used here is a cementitious waterproofing from Ardex called 8+9. This is my new favorite product, since it can work for many different shower builds. It's superhandy for shower niches and benches — they tend to be harder to waterproof with more traditional waterproofing products, but this product, applied with a brush and roller, simplifies the process.
In this photo you can see the shower is full of water. I had just set the flood test before taking the picture.
In this photo you can see the shower is full of water. I had just set the flood test before taking the picture.
Flood testing. Each shower build requires its own steps and safety measures. This shower is under a flood test — when the drain is blocked with a test plug and the shower is tested to see if it holds water.
This should be done for a period of 72 hours for maximum safety; 24 at the very least. Sometimes local codes require only 15 minutes of testing, but checking for longer periods can give you peace of mind that the shower was built correctly.
This should be done for a period of 72 hours for maximum safety; 24 at the very least. Sometimes local codes require only 15 minutes of testing, but checking for longer periods can give you peace of mind that the shower was built correctly.
Flood test control box. This is the second part of a flood test: the evaporation-control box or dish. The water here will evaporate at the same rate of the water in the shower, so you know what can be attributed to evaporation and what can be attributed to potential leaks.
The right drain choice. Waterproofing a shower is only one part of the equation; getting the right drain for the shower is key as well.
The shower often dictates the drain choice. In this photo the linear drain from Noble Company was installed right at the wall and has an offset drain location. For various reasons, a center outlet drain might not have worked in this installation. An offset drain like this can help expand a shower's usable space if it can be done without moving existing drain lines.
The shower often dictates the drain choice. In this photo the linear drain from Noble Company was installed right at the wall and has an offset drain location. For various reasons, a center outlet drain might not have worked in this installation. An offset drain like this can help expand a shower's usable space if it can be done without moving existing drain lines.
Surface area and cleaning. How you clean the new drain is another consideration. A small drain is easier to clean, since it has less surface area. Linear drains have more surface area and will need to be cleaned more often.
I use simple kitchen scrub brushes to clean our shower projects. They make short work of a nasty task.
I use simple kitchen scrub brushes to clean our shower projects. They make short work of a nasty task.
So where's the balance? Let's look at some key drainage pointers and waterproofing products that can help you find the right measures and practices.