Last updated: 2025-12-18
Is there an annoying gap at the bottom of your shower door?
Or perhaps you’ve noticed a persistent gap between the shower door and the wall that turns your bathroom floor into a puddle every morning?
You aren't alone. In the UK, most frameless showers require a specific standard gap to operate smoothly. However, if that gap isn't sealed correctly, it leads to leaks, mould, and even water damage to the floorboards.
Whether you are looking for a shower screen seal white 25mm gap for folding doors or trying to figure out why there is a gap at the bottom of your shower door, this guide will help you identify the exact seal you need.
Quick Navigation: Where is your gap?
- Gap at the Bottom – For leaks between the door and the tray/floor.
- Gap at the Side/Wall – For leaks between the glass and the wall or frame.
- Gap Between Two Glass Panels (Folding/Sliding) – For sliding or bifold door overlaps.
Why Is There a Gap in My Shower Door?
It can be frustrating to see a gap, but it’s actually a deliberate design feature. Whether you have a frameless shower door gap or a gap between sliding shower doors, these spaces are essential for protecting your glass. Without a small clearance, the glass panels would grind against each other or the frame, leading to scratches or even shattering.
These gaps are designed to be filled by specialized seals:
- Gap Under Shower Door: Found in pivot and bifold doors to allow smooth opening over the tray. (Fix it with our Bottom Shower Door Seals)
- Gap Between Shower Doors: Common in sliding shower doors where two panels overlap. (Seal it with our H- F- Seals & Sliding Door Strips)
- Gap Between Shower Door and Frame: Usually found in bifold shower doors or framed units to allow for hinge movement. (Check our Bifold Door Seal Range)
How to Seal Gaps in a Shower Door Effectively
Leaving an open gap under a shower door is a recipe for bathroom dampness. Over time, even a tiny amount of escaping water can lead to mould growth and expensive water damage. However, choose the wrong shower door gap filler, and your door might become difficult to operate.
Next Step:
To help you decide on the best permanent fix, read our dedicated guide: Should I Seal the Bottom of My Glass Shower Door?
In this article, we weigh up the pros and cons of sealing vs. leaving a gap to achieve a watertight finish.
Common Shower Door Gaps We Solve
Whether you have a 4mm shower door gap seal for a tight fit or need a shower door seal for a 25mm gap on a folding unit, we have a solution. We specialize in everything from bath shower screen door seal strips to 3m shower door seals for 12mm gaps.
Frequently Asked Questions
What is the standard gap for a frameless shower door?
There is no single standard, which is why seals come in many sizes. You should measure your specific gap—our range covers 1mm to 35mm. However, for 180° glass-to-glass panels, the UK standard is typically 22mm for magnetic strips.
How to fix a gap in a shower door?
The best way to fill a gap is with a high-quality PVC fin seal. If the gap is at the bottom, use a sweep with a drip rail. If it’s at the side, an H-profile or magnetic seal is the best shower door gap filler.
This article was edited by Laura.