French windows with security glass: standards to be aware of

An essential balance between aesthetics and safety

French windows are a common feature of modern homes, linking interior and exterior spaces and providing maximum natural light. But their large glass surface also makes them particularly vulnerable to break-in attempts. To prevent them from becoming a weak point in the home, it’s essential to choose security glazing that complies with current standards.

Whether you’re building, renovating or reinforcing your home, understanding the safety standards applicable to glazing is essential to making a reliable, long-lasting choice… and one that’s recognized by insurance companies.

Why secure a French window?

Unlike a conventional window, a French window is often accessible from the outside, making it a prime target for intruders. In the absence of shutters or additional protection, glazing becomes the only barrier between the outside and the inside.

Standard double-glazing, no matter how thick, offers very little resistance to impact. A break-in with a sledgehammer or crowbar can quickly shatter the glass, without alarm or sufficient resistance. On the other hand, specially adapted security glass can delay a break-in by several minutes, or even make it impossible without heavy tools.

The main standards to know

EN 356 – Burglary resistance

Standard EN 356 assesses the resistance of glazing to intrusion attempts. It classifies glazing into different categories according to its ability to withstand simulated impacts (steel ball, axe, sledgehammer).

Here are the classes most commonly used in residential applications:

P1A to P2A: basic protection, mainly against accidental impact.
P3A to P4A: intermediate resistance; the glazing withstands several impacts without shattering completely, ideal for exposed French windows.
P5A: high security, resists multiple blows from axes or sledgehammers. Used for shop windows or highly exposed homes.

P4A glazing is often the minimum recommended for a secure French window, especially if it’s located on the first floor or in an area with little surveillance.

EN 12600 – Personal safety

Standard EN 12600 assesses the resistance of glazing to human impact (falls, domestic accidents). It is essential for low, accessible glazing and glazing in public areas.

This standard classifies glazing according to :

their ability to retain shrapnel,
their behaviour in the event of breakage (fragmentation),
the simulated drop height.

Glazing rated 1B1 (the highest rating) means that it withstands high impact while limiting the risk of serious injury, thanks to the use of plastic films between the layers of glass (lamination).

Compliant glazing types

To comply with the above standards, several types of glazing can be used on a French window:

Laminated safety glass (minimum 44.2 or 44.4): two sheets of glass bonded with one or more PVB films.
Laminated glazing + thermal insulation (secure double glazing): combining security and energy comfort.
Tempered glazing, less common, used in specific configurations but more fragile in the event of a targeted violent impact.
Laminated triple glazing for very high-risk areas or passive buildings.

Overall safety: don’t neglect the frame and closure

Glazing isn’t everything. For a French window to be truly secure, it is essential to :

choose sturdy joinery in reinforced PVC, wood or aluminum with reinforcements,
install a multi-point locking system,
secure handle (with lock or knob),
additional burglar-proof film, or connected opening sensors.

At Leader Services, we offer patio doors with EN 356 and EN 12600-compliant glazing, solid frames and high-performance locking systems. Find out more about our services:
https://leaderservices.be/securite/vitrerie/

Conclusion: certified safety for guaranteed peace of mind

To protect your home effectively, the choice of glazing for your patio doors should not be left to chance. Based on EN 356 and EN 12600 standards, you can be sure of real resistance to burglary and optimum safety for occupants.

Do you have a renovation project in mind, or would you like to reinforce your existing joinery? Contact our team via our contact page or by phone. We’ll help you choose, supply and install security patio doors to suit your home.