The waterproofing process

water proofing a bathroom

How waterproofing is done

Any joint between the wall and floor, between the walls themselves, and around any drains in the floor should be prepared and primed appropriately when undertaking a bathroom renovation.  Shower recesses should be smooth and free of any loose particles that will affect the performance of the waterproofing membrane. A polyester reinforcement mat should be installed in all internal corners such as edges between walls and floors, hobs and floors, and corners where two walls meet.  In order to apply the second coat, it is necessary to wait an hour or two after the first coat has been applied. The second coat should be applied in a different direction than the first, for example if the first coat was applied vertically, the second should be applied horizontally.  If the waterproofing hasn’t fully cured, don’t use the bathroom for five days depending on the climate.

Here's a guide to waterproofing your bathroom

To thoroughly clean the floor, use an broom, dustpan and brush, or a vacuum cleaner. Assuming that your bathroom already has a waterproof membrane, the next step is to apply the primer.

Apply the primer to a roller tray with a good roller. Stagger the application from the back of the room. Using the roller, cover the entire bottom half of the wall with primer after you have applied it to approx. 30 cm of the wall. Once all the primer is applied, you can continue to cover the bathroom floor with the roller.

Once the primer is completely dry, you are ready to seal up the holes with silicone. Clean where any previous silicone was. Use paint scraper or a Stanley knife or blade to remove any old silicone. Use a Stanley knife or pair of scissors to cut a hole in the tip of the nozzle large enough to accommodate the silicone. Once you have determined the size of the nozzle needed, you can carefully place it on the space you intend to fill. If the silicone does not dissolve, it will be hard to clean off. To clean the silicone gun, squeeze the trigger while moving it along the line you are sealing. It helps to smooth the silicone over with your finger while moving the gun along the silicone. Now let the silicone dry for 24 hours.

Using masking tape will help you cut around the wall and prevent paint from splashing onto areas you don’t want it to. Place the tape up to the height you want to waterproof the wall, this will give you a straight edge. If you are planning to waterproof the bathroom, you will need to apply waterproofing products. To make the job easier, start applying the waterproofing product in the back corner of the room. Then, use a roller to apply the product. You should roll the roller on the wall width-wise along the wall starting from the floor up to the height of the masking tape you applied to the wall.

Adding the waterproof membrane is the next step. Buy a good quality product. Make sure the waterproof membrane sheet fits the wall and floor cracks, then cut it to the necessary length. Paint the membrane down using a roller or brush with the waterproofing product. Continue until no gaps remain, then fully paint the entire surface.

It typically takes around 24 hours for the membrane to completely dry after painting it with the waterproofing product. Once the waterproofing product has been painted over and dried, the floor surface can be painted.