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SEALANTS, GROUT & JOINTS

Gap Around a Bath

A gap around a bath usually opens because the bath flexes, the frame is poorly supported or the old sealant has failed.

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Fix leaks, movement and moisture before resealing or regrouting

Wear gloves and eye protection. Stop if there is hidden water damage, persistent mould, structural movement or a safety-critical service penetration.

MOST LIKELY CAUSES

Start with these

Bath flexing The rim moves when filled or used.
Poor frame support The bath is not rigidly held.
Sealant failure Old silicone has detached or split.
Gap too wide Silicone alone may not bridge the joint reliably.
◫ Symptom variations Match the exact failure pattern and location. ⌄
  • Gap opens when bath is filled
  • Sealant splits repeatedly
  • Water leaks behind bath
  • Bath moves when stepped into
  • Large uneven joint
✓ Quick checks Simple checks before removing material. ⌄
  1. Check for leaks, damp or movement.
  2. Identify the existing sealant or grout type.
  3. Remove only failed material.
  4. Clean and dry the joint thoroughly.
  5. Choose a compatible flexible product.
1 Step 1 — Check and improve support Remove failed material fully and use products suited to the joint, movement and moisture level. ⌄

Make sure the bath does not move before resealing.

2 Step 2 — Fill the bath with water Remove failed material fully and use products suited to the joint, movement and moisture level. ⌄

Load the bath so it sits in its normal used position.

3 Step 3 — Remove old sealant and reseal Remove failed material fully and use products suited to the joint, movement and moisture level. ⌄

Apply sanitary silicone continuously and let it cure before draining.

⌁ Common causes explained Why sealants, grout and joints fail. ⌄

A gap around a bath usually opens because the bath flexes, the frame is poorly supported or the old sealant has failed.

⌘ Advanced diagnostics Further checks for recurring failures. ⌄
  • Inspect frame and wall battens.
  • Use backing rod for wide joints.
  • Check wall finish and tile edge.
  • Inspect for water damage below.
  • Confirm overflow and waste are not leaking.
▣ Parts and materials needed Common materials linked to this repair. ⌄
  • Sanitary silicone
  • Backing rod
  • Bath frame fixings
  • Sealant remover
  • Finishing tool
! When to call a professional Conditions that should end basic DIY work. ⌄
  • Water is leaking into walls or floors.
  • The joint keeps opening because of movement.
  • Mould or damp is widespread.
  • An unvented cylinder, flue or fire-stopping joint is involved.
  • Tiles or fittings are loose or unstable.
? Frequently asked questions Common sealing and grouting questions. ⌄

Can new silicone be applied over old silicone?

No. Remove the old material and residue first for a reliable bond.

Should corners be grouted or sealed?

Changes of plane usually perform better with a suitable flexible sealant.