How wide should a walk-in shower screen be?

The minimum recommended screen width for a walk-in shower is 700mm to prevent excessive water spray. Most walk-in screens are 800-1200mm wide. The screen should be at least as wide as the shower head spray pattern. For a comfortable walk-in experience, allow at least 400mm entry gap between the screen edge and the opposite wall. Standard UK stock sizes are 700, 800, 900, 1000, 1100 and 1200mm.

Should I use 8mm or 10mm glass for a walk-in screen?

10mm toughened safety glass is the recommended choice for walk-in shower screens. It is more rigid, feels more substantial, and is less likely to flex or vibrate. 8mm glass is acceptable for smaller screens (up to 800mm wide) or where the screen is supported on both sides. All shower glass must be toughened safety glass conforming to BS EN 12150. Larger screens (over 1000mm) should always use 10mm glass.

Do walk-in showers need a tray?

Walk-in showers can use either a low-profile tray or a fully tiled wet room floor. A tray is simpler to install and waterproof but limits design options. A wet room floor (using a former and tanking system) gives a seamless, level-access finish but requires more careful installation. Both approaches need proper waterproofing (tanking) of the surrounding walls.

What type of drain is best for a walk-in shower?

A linear (channel) drain along one wall is the best choice for walk-in showers. It allows the floor to fall in one direction only, simplifying installation. Linear drains also have higher flow capacity than point drains — typically 24-48 L/min depending on length. They create a clean, modern look. Point drains work but require a four-way fall which is harder to tile.

How much tanking does a walk-in shower need?

All walls within the shower area should be tanked to full height (floor to ceiling). The floor must also be fully tanked. Beyond the shower screen, tank at least 300mm past the screen edge on adjacent walls. Use a liquid membrane (2 coats) or sheet membrane with taped joints. Pre-formed corners and drain collars are essential for a watertight system.

Walk-In Shower Calculator — Screen, Drain & Tanking

Calculate glass screen dimensions, channel drain length, tanking area, fall distance and seal requirements for a walk-in shower installation.

Opening Width

Width of the shower area

Shower Depth

Depth from back wall to screen

Screen Height

Standard: 1950-2000mm

Glass Thickness

10mm recommended for walk-in screens

Drain Type

Linear is preferred for walk-in showers

Tanking Wall Height

Tank to full ceiling height ideally

Screen Price (optional)

Glass screen with fixings

Drain Price (optional)

Linear or point drain unit

Tanking Price (optional)

Per m² of membrane applied

How We Calculate This

This calculator sizes the glass screen, determines drain configuration, calculates tanking area and works out the floor fall for a walk-in shower.

The formula

Screen area = (Opening width − 20mm) × Screen height

Fall distance = Shower depth ÷ Fall ratio (1:80)

For a 1200mm × 900mm walk-in shower with 2000mm screen: glass = 1.18 × 2.0 = 2.36 m². Fall = 900 ÷ 80 = 11.3mm. Linear drain = 1100mm.

Glass specifications

8mm: Suitable for screens up to 800mm wide, lighter weight (~20 kg/m²)
10mm: Recommended for all walk-in screens, better stability (~25 kg/m²)
All glass must be toughened safety glass to BS EN 12150
Anti-limescale coatings (e.g. Easy Clean) are recommended for reduced maintenance

Frequently Asked Questions

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Last updated: March 2026

All calculations are estimates. Verify with your supplier.