How to seal a shower

Sealing a shower may sound like a job for the professionals, but with the right know-how, DIY enthusiasts can tackle it confidently and get great results. 

A properly sealed shower keeps water where it belongs, prevents leaking, and helps deter mould and mildew growth which can be a costly job to fix. This guide will take you through the step-by-step for how to seal a shower, neatly and successfully. 

Plus, with EVO-STIK's choice of best sealant for showers, you can trust that the job will provide long-lasting results with no mould, yellowing or peeling in sight.

It goes without saying that water is your bathroom’s best friend and worst enemy. Left unchecked, it can creep into the tiniest cracks, causing damage to your tiles, grout, walls, and even the structure beneath the floor. 

Sealing a shower properly helps in many ways: 

• Prevents water damage
• Keeps mould and mildew at bay
• Maintains a clean, fresh look - especially when using White for Life and Clear for Life sealant
• Extends the lifespan of your shower

Before we get into the step-by-step tutorial, here are our four main points to consider pre-application. 

• Use 100% silicone sealant: Unlike acrylic caulk, silicone is waterproof and flexible, which makes it ideal for areas exposed to moisture, like showers. All EVO-STIK sanitary sealants are 100% silicone. 
• Mould and mildew resistance: Choose a sealant specifically designed for bathrooms as these have added ingredients to resist mould growth. 
• Be cautious of gaps and holes: Even tiny gaps can let water in. Make sure you apply enough sealant to fill every space. 
• Temperature: Don’t seal the shower in cold conditions. The sealant may not bond as well if it’s too cold. Aim for a room temperature between 10°C to 32°C. 

Now you know why it's important to seal your shower properly and some of the key things to keep in mind, let's look at the best way to seal a shower using EVO-STIK silicones… 

• EVO-STIK White for Life, Clear for Life, Bathroom & Kitchen Sealant, 1 Hour Shower Sealant 
• Caulking gun 
• Mild detergent or rubbing alcohol (to clean surfaces) 
• Protective gloves 
• Masking tape (for cleaner lines) 
• Cleaning cloths
• Utility knife or razor scraper (for removing old sealant)

Optional:

• Smoothing tool
• Soapy water

Before you learn how to seal a shower, it's important to remove most of the old shower silicone to ensure you can create a clean, long-lasting seal with your new silicone. 

Ensure your hands are protected with gloves. Then, use your scraper or utility knife to carefully remove most of the old sealant bead. Start by cutting the top and bottom lines of the sealant along the whole length and then pull off the bead from the surface.

Once most of the old shower silicone has been removed, apply a mild detergent on a clean cloth and clean the area to eliminate any residue, dirt, or oils. Removing the residue is essential so that your new shower silicone application can be as smooth and neat as possible. 

Then, leave the shower area to dry. Any moisture left behind will prevent the new sealant from bonding properly. Use the rubbing alcohol and another clean rag to give the edges of the tiles and seams a final wipe down. 

Key areas to focus on include: 

• Around the base of the shower (where the floor meets the wall) 
• Corners 
• Around fixtures like faucets, showerheads, and handles 
• The joint between the shower tray and the wall (if applicable) 

If you want extra clean lines, apply masking tape along the edges where you’ll be sealing. This helps create a neat finish by catching any stray sealant. 

Good to know: If the sealant is tough to remove, a caulk softener or remover gel can help loosen it up for an easier removal. 

You'll want to start by cutting the nozzle according to the seal width you want - we recommend going slightly wider than the sealant gap and ensuring this is at a 45-degree angle.  

Using your utility knife or similar sharp object, cut the top of the cartridge being careful not to damage the thread, then screw the nozzle onto the cartridge.   

Insert the cartridge into the caulk gun and pull the trigger to extract the sealant. 

Here comes the fun part - sealing the shower! Starting in a corner, place the nozzle at a 45-degree angle from the surface and slowly apply the silicone, maintaining pressure so the flow is constant as you work from one end of the shower to the other. 

Good to know: If you can see small waves on the top of the sealant, that means it is overflowing and you have filled the gap between the surfaces. Total filling of the gap is the goal. 

Don’t forget to push the locking metal tongue on the caulking gun to stop the flow of sealant when you end your application. 

Once your sealant is applied, you'll want to smooth out the silicone. You can use a smoothing tool such as a spatula and selecting the right position to suit the angle of your sealant joint, run this over the applied sealant. 

After your first time using the sealant, excess product may collect - discard this. Then, lightly run the smoothing tool, applying almost zero pressure to leave a smooth, perfect finish. 

Good to know: Smoothing the sealant helps to press the sealant into the joint fully, and creates a sleek, continuous bead of silicone for a professional finish. 

Then, remove the masking tape (if used) while the sealant is still wet. Pull it away gently at an angle to avoid smudging the sealant. 

To ensure the longevity of your new shower sealant, let it dry for 24 hours, and ensure the space is well-ventilated. For those sealants that allow for a quicker drying time, such as EVO-STIK 1 Hour Shower Sealant, the area is ready to use in a shorter period. Refer to drying times for your specific sealant using the product's technical data sheet. 

There it is! In six simple steps, you can remove the old sealant in your shower area and replace it with perfectly smooth, clean sealant in next to no time. With EVO-STIK sanitary silicones, the clever anti-mould and waterproof properties ensure your new sealant will look as good as new for years to come!

Although we've shared the best way to seal a shower, mistakes can happen. Here's some of the most common errors made and how to avoid them, helping you to apply your shower silicone perfectly the first time around. 

• Not cleaning the surface properly: Even if the area looks clean, any leftover moisture, soap residue, or old caulk can prevent the new sealant from adhering correctly. 
• Applying too much sealant: Less is more. Too much sealant can result in a messy, uneven line that’s prone to peeling or cracking. 
• Using the shower too soon: Let the sealant cure fully before turning on the water. Otherwise, it might not bond properly and could peel away. 

Once you’ve sealed your shower, a little regular maintenance can keep it looking fresh and functioning well: 

• Wipe down surfaces regularly: After each shower, use a squeegee or towel to wipe down the tiles and glass. This reduces the amount of water that sits on the sealant. 
• Check for wear and tear: Every few months, inspect the sealant for signs of cracking, peeling, or mould growth. If you notice any issues, reapply sealant before it becomes a bigger problem. 
• Ventilation is key: Proper bathroom ventilation (using an extractor fan or by opening windows) helps prevent mould and mildew from building up.