How To Install Kerdi Board Around A Tub

KERDI-BOARD by Schluter is ane of the best means to waterproof a shower.

Here's why: anybody can install it!!!

Plus, information technology's backed by a groovy warranty.

A lot of folks like using cement board only it'southward heavy and requires a waterproofing membrane over it.

Furthermore, if you lot'r working in an older abode KERDI-Lath fits better than cement board in odd spaces.

After today's tutorial you gain the confidence to transform your old bathroom into a new space.

Let's start!!

Here's today's story: we had to remodel a 120 year former bath because the shower looked horrible.

Whew!! That old fiberglass surround was nasty.

Afterwards installing the new tub we had to completely waterproof the stud walls.

Let me tell you, the walls are in way better shape than they were in this picture!!

Plaster and lathe is messy every bit all heck.

We reached out to Schluter to encounter if they wanted to partner with me on this tutorial since nosotros already utilize their materials. They said aye and sponsored this tutorial.

Schluter also watched the video to make sure it met their quality standards…which information technology did!! Thus, you know you're getting expert communication.

Hither are the supplies you need:

KERDI-BOARD
KERDI Trowel
KERDI-Gear up
KERDI-Band
Mapei Kerabond (Unmodified Thin-set)
KERDI Mixing Valve Seal
Screws for KERDI-Board
Washers for KERDI-Lath
Caulking Gun
Painter'due south Record
Impact Driver
Touch on Driver Magnetic Bit
Hammer Drill (Optional)
Mixing Paddle (Optional)
Margin Trowel
5 Gallon Bucket
Grout Sponge
Rags
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Waterproofing this shower involved several unique situations.

First, the chief wall is angled which in plow makes the plumbing wall a bit challenging.

Plus, there's a knee wall that required waterproofing on three sides.

How do y'all beginning a project like this?

Getting Started with KERDI-BOARD

In a traditional bathtub you lot should add together KERDI-Lath to the main wall. And outset past adding the boards at the tub lip that'due south either nailed or screwed into the studs.

But we took a different approach.

This former bathroom has a slanted roof which in plow creates a slanted surface in the tub surround.

And then we decided to start the KERDI-BOARD installation at that slant, i.e. where the vertical studs come across the angled framing for the roof.

Nosotros used 1/ii″ thick KERDI-BOARD which requires the studs to be spaced no more than xvi inches on-eye.

Step 1 is to check the studs are16 inches on-center and plumb. If the studs aren't plumb you lot should accost this problem right away. Otherwise the KERDI-Lath will be installed incorrectly and this will lead to a poor tile installation.

In the picture below you can run across the slanted transition in our tub environs. The KERDI-BOARD sits nice and flush with the studs.

Only employ Schluter screws and washers to attach KERDI-BOARD to the studs. Furthermore, the maximum on-centre spacing for the screws and washers is 12 inches.

KERDI-Lath is one of my favorite waterproofing boards because it'due south low-cal, easy to cut and has lines on it for aligning the screws. These are all things that cement board lacks…

The grid lines brand it super elementary to find the studs and speedily install screws & washers.

How do you adhere KERDI-Lath to the studs?

How to Install KERDI-Lath on the Main Wall

Here's where the fun begins.

Position KERDI-Board on the framing and press a washer into the board every 12 inches up the stud location.

And then drill a single spiral through the washer/KERDI-Lath and into the stud.

Repeat this process until the unabridged lath is installed on the framing.

We really used pieces of leftover KERDI-Lath in this projection. Some of the boards didn't fit the entire length of the main wall.

But that's non a problem. You can cut KERDI-Lath to whatsoever custom size with a utility knife. It's easier to cut than drywall.

If you lot have to cut a KERDI-BOARD to size on the stud merely make sure the board only covers half the stud'south width. That fashion you can identify the adjacent board on the stud (this is similar to drywall work).

Then you lot can pinch a washer on the KERDI-Board seam and adhere both the boards to the stud with ane washer and screw.

Once the top pieces of KERDI-BOARD were installed flush with the ceiling I had to add the lesser boards.

To brand this as precise as possible, I measured from the top of the tub lip to the lesser of the height boards at every stud location.

Then we got the dimensions for where the human knee wall intersected the main wall since one big piece of KERDI-Lath was used for the lower half of the chief wall.

After that panel was cut to size and placed on the wall, we installed a washer & spiral 3 inches up from the bottom of the tub lip. Then added a screw & washer every 12 inches along the stud thereafter.

Yous can save screws and washers past placing them along the seems. The washer will secure both KERDI-BOARDs to the stud when the spiral is tightened.

After the primary wall is installed information technology'due south fourth dimension for the plumbing wall!!

How to Install KERDI-BOARD on the Plumbing Wall

Plumbing walls are always tricky.

There are three holes to cut into KERDI-BOARD on the plumbing wall.

Ane for the tub spout, mixing valve, and shower arm (information technology holds the shower head).

Only this is a breeze since KERDI-BOARDs can be cut with utility knives. Frankly you lot could too use a steak knife, but that wouldn't look too professional.

In this example I measured from the top of the tub lip to the center of the tub spout piping. Why? Because the KERDI-Board is sitting on the tub lip and non the tub deck.

And so we measured over from the main wall to the center of the tub spout pipe.

This will give yous the verbal location of the tub spout on the KERDI-Lath.

Do the exact same procedure for the mixing valve and shower arm.

Transfer those measurements to the KERDI-BOARD and cutting a circle using a utility knife.

If you're using the Schluter KERDI mixing valve seal, center it on the measurement for the mixing valve. So trace the outline of the mixing valve seal onto the KERDI-BOARD and cut it out.

Like shooting fish in a barrel stuff.

Slide the KERDI-Board over the plumbing and brand any pocket-size adjustments with your knife.

If you lot've always worked with cement board you know it is heavy. And any small-scale adjustments aren't done with a utility knife nearly of the time.

We secured the board to studs using the same specifications that were used for the main wall, i.eastward. every 10-12 inches along the stud and three inches up from the tub lip.

A piece of KERDI-Lath was added along the edge of the tub.

This configuration is wonky as all heck because our door casing will be inside the tub surround and embrace that sliver of KERDI-Board

Don't worry, the door casing is fabricated of PVC and waterproof.

Only still…it'due south not ideal to have door casing in the shower.

The final wall to build with KERDI-BOARD was our knee wall.

How to Install KERDI-BOARD on the Knee joint Wall

Knee joint walls are fantastic because they create the illusion of space. And nosotros certain needed that in this small bath. I can touch the pedestal sink, toilet and knee wall from one location.

IT'Southward Pocket-sized.

We desperately needed a genu wall in this bathroom to permit low-cal from the window to pass into the shower.

Tempered glass will sit on the knee wall and provide a fantastic look. It'due south going to price $400-$500 merely well worth it.

Merely three sides of the knee were waterproofed.

We installed KERDI-Lath on the face of the knee wall first and used one screw/washer every 10 inches for extra strength.

And so the top using one spiral/washer for every stud.

And finally the final board was installed only like the other ones.

Almost forgot, we did place a small piece of KERDI-Board adjacent to the tub just similar on the plumbing wall.

Here are some pictures of the KERDI-Board installation before nosotros waterproofed the seams.

We love seeing all the boards neatly installed. Information technology's a nice feeling of achievement.

Once all the boards are installed the last step is to seal the seams with KERDI-BAND.

The tub lip to KERDI-BOARD transition is ane of the about of import places to waterproof. Fortunately Schluter has an awesome method for making this leak proof.

How to Waterproof the Tub to KERDI-BOARD Transition

First, apply painter'south tape to the tub deck.

We're doing this considering KERDI-FIX volition fill the gap between the tub and first row of KERDI-BOARD. Simply you don't desire to get KERDI-Set up on your new tub only because it can be messy.

Utilize KERDI-FIX to the tub lip using a caulking gun.

You lot'll meet in our video that there's a generous bead of KERDI-Fix in this gap.

KERDI-Ready also covers upwards the screws that hold the tub to the studs. This is nice because the screws are another place where water can leak into the stud bay.

Some might call up this is a fleck extreme, but nosotros don't care because you tin never have enough waterproofing. We also practical a dewdrop of KERDI-FIX between the small-scale section of KERDI-BOARD and tub.

My thinking is this, that area is going to go saturated with water and nosotros want it to be heavily waterproofed.

Use a iii inch notched trowel to embed the KERDI-Set in the tub lip gap.

You lot tin can also use KERDI-FIX to waterproof where the tub spout comes through the KERDI-BOARD.

We chose to do this method just you can also buy special Schluter tub spout covers.

The next stride is to embed KERDI-Band into the KERDI-Fix to brand the tub to KERDI-Board transition 100% waterproof.

How to Add KERDI-Ring to KERDI-BOARD at the Tub

Now that the KERDI-BOARD is installed you lot take to waterproof all the seams. And the way to exercise that is to use KERDI-BAND on every seam and screw.

This is important: utilize unmodified thin-set to embed the KERDI-Band.

Schluter calls for the unmodified sparse-ready and since they're the experts I think information technology's important to follow their directions.

Nosotros used Mapei'southward Kerabond sparse-fix.

Mix Kerabond according to the directions. It should be smooth, free of lumps and have a slightly more than fluid consistency than what would be used to embed tile. The Kerabond should just barely autumn off a vertical trowel.

To install KERDI-Band onto KERDI-Lath you lot can use ii different types of trowels.

Use either a 1/iv ten 3/16 inch v-notched trowel or the Schluter-KERDI trowel which is a 1/8 x 1/viii inch square-notched trowel.

We also recommend having a 5 gallon bucket of water and a sponge to help with this process.

Start the KERDI-BAND process at the tub to KERDI-BOARD transition.

Use Kerabond to the lesser 3 inches of KERDI-BOARD where it meets with the KERDI-Set up. Utilise either the flat side of the Schluter-KERDI trowel or a 6 inch joint chemical compound knife.

Comb in additional thin-set with the notched side of the trowel. Keep the sparse-fix ridges running in i direction to preclude air pockets.

Do this for the entire tub to KERDI-BOARD transition. Then embed the KERDI-Band into both the Kerabond sparse-fix and KERDI-FIX with the flat side of your trowel. Yous'll accept to cut a hole in the KERDI-BAND for the tub spout.

We adopt to use one continual piece of KERDI-Ring for the tub to KERDI-Board transition.

Make certain to remove air bubbling between the KERDI-Band and KERDI-BOARD. Wipe excess sparse-set off the KERDI-BOARD with a damp sponge.

After embedding the KERDI-Band you can remove the painter's tape from the tub. Another important tip: don't go out the painter'due south tape on the tub for more than ten minutes as the KERDI-Fix will bond to it.

Now you tin can move onto covering the rest of the seams and screws/washers with KERDI-Ring.

Finishing the KERDI-Band Installation

Your shower or tub will be waterproof later on you complete this next footstep.

Embed KERDI-Band onto every seam using the aforementioned method. Cardinal thin-set onto articulation, comb in additional thin-prepare, center the KERDI-Band on the joint and embed information technology with the apartment side of your trowel.