Toughened Safety Glass - Cat flaps fitted London
Step-by-Step Process to Make Toughened Safety Glass
How your cat flap singe glazed or double glazed unit for your window or Door

Glass Cutting and Preparation
- The glass is first cut to its final size and shape from standard float glass.
- All edges are smoothed or polished to prevent stress points, as toughened glass cannot be cut or altered after tempering.
Washing and Inspection
- The glass is thoroughly washed to remove dust, oil, or debris that could cause defects.
- It's then inspected for any surface flaws, chips, or cracks.
Heating in a Tempering Furnace
- The clean glass enters a tempering furnace, where it's heated to around 620–680°C (about 1148–1256°F) — just below its softening point.
Rapid Cooling (Quenching)
- The heated glass is then rapidly cooled using high-pressure blasts of air from multiple nozzles.
- This rapid cooling (quenching) takes just a few seconds and cools the surface much faster than the interior.
Stress Formation
- This cooling process creates compressive stress on the surface and tensile stress inside the glass.
- These internal stresses are what give toughened glass its increased strength and shatter-resistant properties.
Quality Testing (Optional)
- Some manufacturers test samples for strength, optical quality, and fragmentation behavior (how it breaks under force).
Key Benefits of Toughened Safety Glass
- 4–5x stronger than regular float glass
- Breaks into small blunt fragments (reducing injury risk)
- Heat-resistant and impact-resistant
- Complies with BS EN 12150 and BS 6206 (UK standards)
Important Notes
Cannot be cut, drilled, or reshaped after tempering — all alterations must be done beforehand.
If the glass is damaged during tempering or has impurities, it may spontaneously shatter (rare, but preventable with heat soak testing).
Cat Flap Toughened Glass - Supplied & Fitted
Cat Flap Toughened Glass Windows - Single Glazed
Cat Flap Toughened Glass Doors - Single glazed
Cat Flap Toughened Glass Doors - Double Glazed
Cat Flap Toughened Glass Sealed Units.
We also fit cat flap in:-
Hard woord doors, metal doors, upvc doors, fences, garage door and many more...
Call the London toughened glass Catflap professionals
Cat Flaps, Dog Flaps, Single and double glazed
Cat Flaps in Wooden Doors - Cat Flaps in UPVc Panels - Cat Flaps in Glass & Double Glazing - Dog Flaps