How do people waterproof a concrete shower floor?

Waterproofing a concrete shower floor is a crucial step to prevent water damage and mold growth. Here are the primary methods used today:

Sheet Membranes

Sheet membranes are plastic compounds that are attached directly to the tile backer board and shower surface. They often come with "peel and stick" technology for easy installation. These membranes are durable and provide a strong barrier against water penetration12.

Liquid Membranes

Liquid membranes act like waterproof paint. They are applied with a paint roller and, once dried, form an elastomeric layer that remains flexible. This method is popular for its ease of application and effectiveness. RedGard is a well-known product in this category124.

Foam Wallboards and Bases

Foam wallboards, like Kerdi Board, and foam shower bases are made from extruded polystyrene foam and provide both structural stability and waterproofing. These are often used in conjunction with other waterproofing methods for added protection14.

Preslope Shower Pan

A preslope shower pan involves creating a sloped mortar base to direct water to the drain, covered with a waterproof membrane. This method ensures that any water that penetrates the tile and grout is directed towards the drain, preventing pooling and subsequent damage2.

Installation Tips

Preparation: Ensure the concrete floor is clean and free of debris.
Application: For liquid membranes, apply the product with a roller, ensuring even coverage. For sheet membranes, peel and stick them onto the surface, ensuring no air bubbles.
Sealing: Use silicone to seal any screw holes or penetrations to maintain the integrity of the waterproof layer.
Corners and Seams: Pay extra attention to corners and seams by using additional fabric or tape to reinforce these areas124.

By following these methods, you can effectively waterproof a concrete shower floor, ensuring long-term durability and protection against water damage.

Key insights

The importance of following guidelines and instructions when applying primer for waterproofing the bathroom floor.

️ It's important to wait 24 hours for the silicone to dry after filling the cracks.

When waterproofing up to the shower recesses, the waterproofing agent needs to be applied at least 1.8 meters high.

🧤 Using a paintbrush instead of a roller can make the process easier and more manageable.

Timestamped Summary

00:00 Clean and prime the floor before applying waterproofing products.

00:34 Apply primer, fill cracks with silicone, scrape away excess, wait 24 hours for drying.

00:54 Apply masking tape to the area to be waterproofed, then apply waterproofing agent from the back corner to the front.

01:18 Apply waterproofing and membrane in multiple coats, let it dry for 24 hours, and remove the tape to waterproof a bathroom floor.

Video Full Text

00:00 I'm going to show you how to waterproof the bathroom floor. These are my tools I'll be using; got a bit of cleaning equipment, some safety equipment, got my primer, my stirrer, my hammer, my knife. So I have my spirit level, my scraper, my membrane, my caulking gun, and I got my silicone and my waterproofing product here. With our first step, we'll be cleaning the area free of dust and make it nice and smooth. And our next step is to apply the primer. Make sure you follow the guidelines and instructions on how to do so.

00:34 When applying your primer, it's good to start from the back corner and work your way forward. It's also good to go up the wall a little bit. Now that the primer has dried, we're going to fill the cracks with silicone. Now I'm going to scrape away the excess with my spatula. I've now waited 24 hours for the silicone to dry.

00:54 Now I'm going to start my waterproofing process. I'm now going to apply some masking tape. I'll apply it to the point of where we will be waterproofing. So we do not go above that. I'm doing the bathroom floor, but if I was going up to the shower recesses, I would have to go, at least, 1.8 meters high. So next step I'm going to apply the waterproofing agent, starting from the back corner and working my way forward.

01:18 Once I've done my first coat of waterproofing, I can then put on my membrane focusing on the joints and the cracks. I'll now roll the membrane out. So I can cut to size the measurements that I need. I'm just doing bits at a time so I can still reach to the corners. Now in order for this to stick, I'm going to apply some more waterproofing on top of it. Now if you do find it easier, you can use a paintbrush instead of a roller. I'll now continue to apply the waterproofing agent and membrane the rest of the floor. Now this junk can be messy sometimes so you might want to put your gloves on. Now that I've been around the outsides, I'm going to continue waterproofing the floor, focusing on the joints and applying the membrane. Now I've finished applying my first coat of waterproofer and the membrane. I'm going to let it dry for 24 hours. Now I've waited 24 hours, I'm going to apply my second coat. Now I've applied my second coat of waterproofing, I'm going to leave that to dry for 24 hours and that's the job done. Don't forget to take the tape off. And that's how you waterproof a bathroom floor.