Burglar resistant windows: what really keeps intruders out

A window resists a break-in through three things working together: hardware with anti-lift locking points, laminated glass that is hard to break through and a lockable handle. Resistance class RC2, defined by European standard EN 1627, means the complete window has been tested against an opportunist burglar using simple tools.

By Marcio Barros · Updated 31 October 2026 · 5 min read

The three things that matter

1. The hardware

Most break-ins happen by forcing the sash open with a tool. Mushroom-head locking points that engage in security keeps stop the window being levered open. The more of them around the frame, the better.

2. Laminated glass

Laminated glass is made of two panes bonded together by a film. It can crack but stays in place, which slows an intruder down a great deal. It can be built into double or triple glazing.

3. The handle

A lockable handle or a push-button handle stops the window being opened from outside after someone has drilled through the frame or the glass.

RC2 and RC2N security windows

Standard EN 1627 tests the complete window: profile, hardware, glazing and handle. For RC2, the whole unit must hold out for at least 3 minutes against an attempt with simple tools. The RC2N variant uses non-laminated glass.

Front doors and sliding doors

The front door and sliding doors are often the weak points. A door with a multipoint lock and a sliding door with anti-lift locking make a real difference. See our front doors and sliding doors.

ExploreFront doors made to measure in Luxembourg

FAQ

What does RC2 mean for windows?

RC stands for Resistance Class. Standard EN 1627 grades windows and doors from RC1 to RC6. RC2 means the window has been tested against a break-in attempt with simple tools, such as a screwdriver or pliers.

Do all my windows need to be burglar resistant?

Start with the most exposed ones: the ground floor, windows hidden from the street, French doors and sliding doors that can be reached from the garden.