How to seal the gap between a bath and a tiled wall

Sealing the joint between your bath and the tiled wall stops water getting behind the bath and causing damage. This guide covers cleaning the gap, filling the bath first, running an even bead of sanitary silicone and smoothing it for a neat finish. It suits any beginner with a cartridge gun.

How to Seal a Bath | Wickes, by Wickes on YouTube. 2 min 29 s.

Video length
2 min 29 s
Time to do it
45 minutes plus curing time
Difficulty
Easy
Steps
7

What you need

Steps

  1. Scrape out all old sealant from the joint with a knife or sealant remover. Wipe the bath edge and tiles with a cloth so the area is clean, dry and dust free.

  2. Fill the bath with water before you start. The weight pushes the bath down so the sealant sets at the same position it sits in when full.

  3. Put on protective gloves and cut the nozzle of the cartridge at an angle with a Stanley knife, cutting away from your body.

  4. Load the sanitary silicone cartridge into the gun and check the nozzle size suits the gap, roughly 5 to 6 mm wide.

  5. Run an even bead of sealant along the full joint, keeping steady pressure on the trigger and pushing the gun forward.

  6. Smooth the bead with a silicone finishing tool or a wet finger dipped in soapy water. Work in one pass for a tidy line.

  7. Leave the bath full of water until the sealant is completely dry, usually 24 hours. Then drain the bath and check the seal.

Tips and common mistakes

Use sanitary silicone rather than general purpose sealant, as it resists mould in damp bathrooms.

Never seal an empty bath, or the joint can crack open the first time someone fills it.

Keep a roll of kitchen paper handy to wipe the nozzle and your tool between passes.

Don't touch the smoothed bead until it has fully cured, or you will leave marks.

Questions

How long does bath sealant take to dry?

Leave it about 24 hours, and keep the bath filled with water during that time. Check the maker's label on the cartridge for the exact curing time.

Can I seal a bath without filling it first?

It is not recommended. The bath flexes when filled, so a seal made on an empty bath can pull away and leak.

Do I need to remove all the old sealant?

Yes. New silicone will not stick to old sealant or to damp, greasy surfaces, so strip it back to clean tiles and bath.

This guide was drafted from the video's details and general task knowledge. It has not been checked against the full video. Check the video and relevant product instructions before following a procedure. Report a correction.

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