How To Silicone A Shower

Not appropriately sealing your shower can cause both structural and health risks. As showers (and your bathrooms in general) are exposed to water daily, you will need to have adequate measures in place to ensure water can’t penetrate into the nearby appliances.

Below are some common examples of why it’s important to seal your shower.

Structural damage

• Tile - water can seep behind the tiles and damage the wall behind it. It can also crack the surrounding grout which can mean that the tiles become loose. If your bathroom is located upstairs, it can also cause staining/discolouration on the ceilings below.

• Rot - floor joists can rot and stud walls can weaken (especially in timber-framed houses). In severe cases, floors can become unsafe and potentially require new flooring.

Health risks

• Black mould & mildew - if you have moisture trapped behind the wall/gaps, it can create the perfect environment for mould to grow. Even if you can’t see it, black mould can grow inside the walls and can be very difficult to get rid of once it’s within the structure. This can pose serious health issues for you if not treated; symptoms including respiratory issues, fatigue and severe headaches.

• Bacterial growth - consistent dampness can also support bacterial growth, which can pose a serious health risk. Stagnant water in particular can create an environment for bacteria to spread.

• Allergies - spores can cause skin irritation, coughing and worsen asthma symptoms. Children, high-risk individuals and vulnerable adults are most at risk.

In this step-by-step guide, we’ll walk you through the key elements of how to silicone your shower.

Step 1. Remove old silicone

Before siliconing your shower, you will need to remove any pre-existing sealer. Using a utility knife (or scraper) you will need to cut along the edge of the old silicone and peel it away completely. Ensure you’re careful when doing this as to not scratch, mark or damage the surface. Ensure all residue is removed, as leaving any there may affect future bonding. Thoroughly wipe and clean the area and leave to dry fully. 

Additionally, there are specialised silicone removers available if you’d prefer to use this instead of a knife/scraper.

Top tip: for stubborn areas, try using a pair of tweezers to remove the smaller strands of silicone. You can read our guide on how to remove silicone sealant for more tips.

Step 2. Apply masking tape

For straight, clean lines you can apply masking tape along both sides of the joint to ensure accuracy. Leave a small gap (usually around 3mm) for the silicone to go and press the tape firmly down to prevent any bleeding underneath. By following this technique you should ensure the best, professional result.

Step 3. Prepare the sealant gun

When choosing your silicone, it’s important that it’s sanitary and mould-resistant if possible. This will ensure a watertight solution and prevent water ingress around your shower. 
Using your utility knife, cut the very end of the sealant tube (at a 45° angle). It’s best to start with a smaller opening and cut more later if needed. Place the tube in the sealant gun and squeeze the trigger until the silicone comes out of the nozzle. Most caulking guns have a built-in poker to puncture the seal, but you may need to do this yourself if this doesn’t work.

Step 4. Apply the silicone

Holding the sealant gun at a 45° angle (roughly), steadily apply the silicone between the masking tape lines in one smooth, continuous motion. Try to avoid stopping and starting, as this can cause lumps and inconsistent silicone flow. It’s usually better to apply too much than too light - so don’t worry if you think you’ve added too much.

Step 5. Smoothing the silicone

Once you’ve applied your silicone, you’ll need to smooth over the joints for a neat, crisp finish. To do this, you could use a smoothing tool or you could lightly wet your finger for more precision. 

Run your smoothing tool (or wet finger) along the silicone in one steady sweep - this should remove any excess sealant and ensure the gap is fully filled. When you’re happy with the result, remove the masking tape while the silicone is still wet (the quicker the better) to avoid it sticking.

Top tip: don’t overwork it, as removing too much silicone may result in an undesired look.

Step 6. Leave to cure

The sealant should dry pretty quickly, but it’s important to leave it to fully cure for at least 24 hours after application. You should avoid using the shower until it has cured as any moisture on the seal will disrupt the adhesion process and you may need to reapply.

You could speed up the curing process by ensuring good ventilation (such as a fan or dehumidifier) - but you should always leave for at least 24 hours for best results.