Tile and Finish the Shower Floor Repair

I covered the basics of waterproofing a shower using the Schluter Kerdi system in my last post (click here). Now it's time to lay the tile and grout it all.

The goal of this project was to just to replace the bottom rows of tile and the shower floor. The older system was leaking and needed to be torn out (see this post). In addition to leaking, the old tiles weren't looking very good and some dirt had been collecting in areas that had been caulked several times in an attempt to fix the leaks.

The layout for the tile was already dictated to me by the original tiles that I didn't remove. I would be using a rounded base tile at the intersection of the bottom of the wall with the floor. This piece would get cut to fit after I installed the wall tiles.

In this case, I would need to start laying tile at the top and go down from there. If you start at the bottom, the weight of the tile is supported by the floor. Starting at the top, I had to tape each piece to the tile above so that they wouldn't slide down the wall and out of place.

One great thing about the Schluter Drain is that is a 4" square. It's perfectly sized for most tile installations where you are using either 1", 2", or 4" tiles. In my case, I installed 2" square white tiles by cutting out the center of one sheet of tile and installing this first (see the picture below). Then I installed all the tile sheets around the perimeter.


The small ledge across the bottom of the doorway is called the curb. It keeps the water contained in the bottom of the shower. I used some curved edge pieces of tile on the corner of the curb to avoid any sharp corners.

After grouting with white unsanded grout and sealing, this shower was ready for business. Hopefully, it will last for decades to come with no more problems.

HINT: John Bridge (Tile guy extraordinaire at www.JohnBridge.com) says that for a maintenance-free shower, take a minute after each use to wipe down the tile with a towel. This will greatly reduce any mildew over time and keep it cleaner as well.

-Peter


www.CarpentryGuy.com

Waterproof the Tile Shower With Schluter Kerdi

What the heck is Schluter Kerdi???

It's a fairly new system for waterproofing showers that involves installing a membrane (the Kerdi) throughout the shower and over their special Kerdi drain. When finished you'll have a completely waterproof, sealed shower. In fact, it's so waterproof that you can install the Kerdi right over regular old drywall. That says a lot.

Let's look at how I installed the Schluter Kerdi shower system when I was repairing and old leaky shower pan liner that was decades old. In my last post (this link), I tore out the old tile down to the framing. Next, I replaced the subfloor with new plywood and added 1/2" Hardibacker on the walls. (Yes, I could have used 1/2" drywall, but I had the Hardibacker on hand...)

INSTALL THE PRE-SLOPED SHOWER TRAY
The older method to doing a shower floor included making a sloped bed of mortar that would direct water toward the drain. This needed more time, labor and expertise. For this shower, I used a Schluter pre-sloped shower tray. It's made out of some kind of foam and is easily cut to fit your particular shower.


After cutting the tray to size, I dry-laid it in place to mark the spot for the drain. Once the drain hole was cut out, I covered the floor with unmodified thinset mortar using a 3/16" v-notch trowel. The shower tray sets in this. You can walk around on it to make sure it's well embedded in the mortar. Just be careful not to crush it with your knees as you are working- it is foam after all.

INSTALL THE KERDI MEMBRANE
I'm not going to go through every detail of installing the membrane. If you are interested make sure to get the Schluter installation DVD and check out www.Schluter.com. The DVD comes with the shower kit and is great at showing every step along the way.

Basically, the membrane is installed over a thin layer of mortar and then flattened out and embedded using the straight edge of your trowel. The edges must all overlap by a minimum of 2". I started by using something they call Kerdi-Band in all the bottom corners. (It's just a thin pre-cut strip of the Kerdi material.)

It helped to have two trowels or a putty knife so you can hold the membrane in the corner with one trowel while you smooth out the other side with the other one. It's important to have tight square corners so that your tile will fit together correctly.

Once all the corners are done I installed larger pieces of Kerdi on the walls that overlap the corner pieces. Smooth them out to make sure there aren't any air bubbles underneath. Schluter also makes special corner pieces that a pre-formed to fit into corners and over the curb corners.

INSTALL THE KERDI DRAIN

The walls are done- let's do the floor. I covered the floor with a layer of mortar and then pressed the Kerdi Drain into place. The flange has openings that will help it firmly integrate into the mortar. I spread a little more mortar around the flange and installed the Kerdi membrane, making sure to fully embed it, especially around the drain.

That's it! Let it set overnight and we'll be ready to install the tile.

-Peter

www.CarpentryGuy.com

Redo a Tile Shower Floor- Tearout

Tile shower floors are nice, unless they are leaking! This is the case for a Nashville homeowner that asked me to repair their shower floor.

This was an old shower that was likely 40-50 years old. The way of installing a shower back then (and still today in some cases) was to first install a waterproof membrane that goes around 8" up the walls all the way around. Then, a sloped bed of mortar or 'mud' is installed before tiling the floor. A specific type of drain is used that makes a seal with the membrane.

Many people have the misconception that grout is waterproof. This is not true. Most of the water is deflected and just goes down the drain, however, a small amount is absorbed through the grout and mortar. When it gets to the waterproof membrane the water is funneled to the drain and through tiny 'weep holes' that send the water down the drain.

My guess is that the weep holes were clogged with this shower. This meant that the mortar bed was saturated with water and it was full enough that it was dripping over the top of the membrane around the sides. I saw evidence of this when I started removing the bottom tiles and water started pouring out from behind.

TEAR IT OUT

The homeowners didn't want to replace the entire shower and I can't blame them. This is expensive work. Instead I would just be tearing out the bottom few rows and installing a new waterproofing system called Kerdi from Schluter Systems. First, I had to get dirty.

Getting started was easy because many of the tiles were loose anyway and came right off. After that I went around with my hammer and a flat bar and busted out the tile. Of course, I was careful not to damage the tile above that I wanted to keep.

The wall tiles were set on a mortar bed containing wire mesh for strength. Below that was the black shower membrane that had to go. It all chipped away fairly easily exposing the thick mortar bed under the floor of the shower. This mortar didn't contain any mesh and broke apart into pieces that I could just scoop up and dispose of.

Finally, I had worked my way down to the subfloor that was wet and needed to be cut out. It wasn't long before I was looking into the basement and ready to start putting it all back together.

-Peter

www.CarpentryGuy.com