Today we’re prepping to tile in the kitchen and bathrooms. Having seen firsthand how much damage water can cause to a home, I want to show you this tutorial for How to Waterproof Floors!

Waterproofing Floors in Any Room

Renovations are finally moving forward at Millie’s Remodel. This is the point where I feel like we already hit rock bottom and now we’re finally on the rebound. You might remember we used a self-leveling concrete in the kitchen last week. Now it’s time to waterproof the floors to prevent damage from ever happening again!

Last year I took two Schluter classes and learned about waterproofing, uncoupling membranes, and tips and tricks to keep your tile job looking flawless for a lifetime. What I learned over the four days blew my mind. I learned why and how shower systems fail. But, most importantly, I learned how to properly prepare surfaces for tile using waterproofing membranes. Today we’ll just be talking about waterproofing a floor, but I’ll have another tutorial for you soon so you can learn how to waterproof walls too.

Materials:

(I’ve included affiliate links for your convenience. I earn a small percentage from a purchase using these links. There is no additional cost to you. You can read more about affiliate links here.)

Why should you waterproof a floor?

Before we get started, I want you to fully understand how waterproofing a room can actually save you money and save you from the headache of having a leak in your home.

If you have a kitchen or a bathroom, chances are you’re going to have a leak in your lifetime (or your home’s lifetime) if it hasn’t already happened. One of the best things you can do is to install waterproofing materials so water can never damage your floors or floor framing again. I believe so strongly in the Schluter products, that all the properties I’m working on (including my own) will have Ditra installed on the floor before tiling.

By using the Schluter Ditra uncoupling and waterproof membrane in conjunction with Kerdi band around the perimeter of the room, I can waterproof the entire floor. Which means I don’t have to worry about rot or mold happening. Any little leaks will sit on top of this membrane until I see it because the water will rise instead of seeping into your floor or walls.

Ready to get started? Let me show you how to waterproof any room in your house!

For your convenience, I made a video to help show how to install Schluter waterproofing products and how to fully waterproof a room!

Instructions:

  1. Cut open your roll of Ditra and roll it out onto a scrap piece of wood or something you can cut on.
  2. Measure the room you want to waterproof and transfer the dimensions onto your Ditra membrane. Use a straight edge and a sharp utility knife to cut the Ditra. You might need to make a few passes with the knife to cut completely through the Ditra membrane.
  3. Test fit the Ditra in your room. Cut out a hole for your floor vents by pressing your knife through the membrane where the vent is and remove the material up to the edges of the duct. Cut the rest of the pieces to fill the room. Do not overlap the Ditra material.
  4. Now it’s time to mix the thinset. When using Schluter Ditra it’s highly recommended to use the Schluter All Set. This mortar is specifically manufactured to cure against the waterproof membrane. Read the instructions on the packaging and mix your thinset as directed.
  5. Use a wet sponge and clean water to clean and wet the subfloor. Spread the thinset onto the floor using the Schluter Ditra trowel. Make sure you have good coverage on the floor.
    Then use the notched trowel to comb through the thinset at a 45° angle.
  6. Lay the Ditra membrane on top of the thinset and use a smooth float to press the membrane into the thinset. In the beginning, you should roll back a corner of the Ditra to make sure you have full coverage onto the backing of the membrane. Place the Ditra back down and use the float again to make sure the membrane is pressed into the thinset.
  7. Use a wet sponge to clean out any mortar that has squeezed out the seams or edges.
  8. Once all the Ditra has been installed into the subfloor, you’re ready to seal the perimeter and seams. Grab a Kerdi corner piece for each corner of the room. Using the Kerdi trowel, apply thinset mortar to the inside corner of the room. Use the notched side to comb through the thinset. Place the Kerdi corner into the thinset and use the flat side of the trowel to embed and scrape along the Kerdi.
  9. Now you’re ready to install the Kerdi Band on the straight sections of wall. Be sure to cut your Kerdi band so it overlaps the corner pieces by at least 2 inches. I like to pre-fold my Kerdi Band by creasing it in the middle so it’s easier to install in the corners. Apply the Kerdi Band to the wall and floor using the same technique as the corner.
  10. Clean up any excess mortar leaving a smooth surface for tile installation.
  11. Now it’s time to complete the waterproofing of the room by sealing the seams between the Ditra sheets. Cut your Kerdi Band so it overlaps any perimeter band by at least two inches. Apply the thinset over the seam, use the notched trowel to create ridges in the thinset.
    Then embed the Kerdi band into the mortar and run the flat side of the trowel over the band to smooth the thinset and embed the band.
  12. Clean up any excess and allow the thinset to cure before tiling.

Once the thinset has cured you can tile your room and rest easy knowing this room is waterproofed and there’s no way the subfloor will rot from a sneaky little leak. Or a big leak if you have kids that like to splash out of the bathtub. I know this risk all too well from my own boys.

I hope you found this tutorial helpful and you’ll consider using Schluter waterproofing materials before you renovate your next “water” room.

Disclosure: I was provided with some Schluter materials for this project. I was not told what to write. All opinions are my own. I am particular about the brands I represent and will always let you know when you are reading a post with complementary products or a sponsored post.

2 replies
  1. Mariele Storm
    Mariele Storm says:

    The video is private. 🙁
    I’m guessing you can’t use this if you’re using cork or vinyl flooring? I hate tile in kitchen, but would also like to have waterproof security under my floors…!
    Thank you for the tutorial. 🙂

    Reply

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