RC2 Windows: Security, Standards, and Specifications.

In modern building design, security is not a luxury—it's a necessity. Among various security measures, windows often represent a critical vulnerability. To address this, the European Union has established specific resistance classifications for burglary protection. One of the most common and practical levels for residential and commercial use is RC2 (Resistance Class 2). This blog post delves into the technical aspects of RC2 windows, their construction, compliance requirements, and appropriate use cases.

What Are RC2 Windows?

RC2 windows conform to the specifications outlined in the EN 1627 standard, which defines resistance classes RC1 through RC6. RC2 provides moderate protection against burglary and is recommended for easily accessible windows and doors in residential or light commercial properties.

The classification implies that the window resists forced entry attempts using simple tools such as screwdrivers, pliers, and wedges for at least three minutes. While this may seem minimal, in real-world scenarios, most burglars abandon attempts within that timeframe if no progress is made.

EN 1627 and RC2 Testing Methodology

RC2 certification is based on both static and dynamic load testing, as well as manual testing. These tests simulate real-world break-in attempts.

1. Static Load Test: Force is applied to the window frame, sash, and locking points using hydraulic pressure in specified directions (inward, outward, and shear). For RC2, the pressure values are:

• 3 kN on locking points
• 1 kN on infill elements (e.g., glazing)

1. Dynamic Load Test: A pendulum test drops a 50 kg weight from various heights to simulate impact from a human body or object. The RC2 level requires the window to remain intact after three such impacts.
2. Manual Attack Test: Simulated burglary attempts are carried out using a defined set of tools:

• Screwdriver
• Pliers
• Wedges
• Hammer (only for additional components, not direct glass attack) Attack duration: 3 minutes of active attack time (excluding tool switching or repositioning)

These tests must be performed by an accredited testing laboratory, and all elements of the window (frame, sash, glazing, hardware, and mounting) must work in unison to pass certification.

Construction Requirements of RC2 Windows

RC2 windows integrate several reinforcements to achieve the resistance class. These include:

• Reinforced Profiles: Both the sash and the frame must use profiles capable of withstanding significant mechanical force. For PVC windows, this typically involves galvanized steel reinforcements with minimum thicknesses.
• Security Hardware: Multipoint locking systems with mushroom-head security cams and matching striker plates are essential. Hinges are often reinforced and equipped with anti-lift protection.
• RC2 Glazing: Windows must use laminated safety glass classified to at least P4A as per EN 356. This means two or more layers of glass with interlayers (typically PVB) to resist impact and delay penetration.
• Secure Fixing and Installation: The window must be installed using mounting methods compliant with RC2 requirements, such as wall plugs and screws tested for tensile and shear strength. The building structure where the window is installed must also be capable of withstanding the same load requirements.
• No Weak Points: Any ventilation systems, openers, or fittings must be tested and designed not to compromise the RC2 certification. Even the glazing bead system must prevent glass removal from the outside.

Certification and Documentation

Manufacturers offering RC2-compliant products must provide:

• Test reports from a notified body (e.g., IFT Rosenheim, PIV Velbert)
• A Declaration of Performance (DoP) in line with the Construction Products Regulation (CPR)
• Clear labeling on the product or accompanying documentation

It's important to note that partial compliance (e.g., only the glazing or only the frame) is insufficient. The window as a whole unit, including accessories and installation method, must meet the RC2 standard.

Use Cases and Limitations

RC2 windows are ideal for:

• Ground-floor windows in residential buildings
• Balcony and terrace doors
• Basement windows
• Accessible commercial or office properties

However, RC2 is not designed to stop professional burglars using power tools or targeting high-value installations. For those situations, RC3 or higher may be more appropriate.

Additionally, RC2 does not cover bullet resistance or fire resistance—separate standards apply for those performance areas (e.g., EN 1522 for bullet resistance, EN 13501-2 for fire classification).

Maintenance and Longevity

Security windows must maintain their integrity over time. Regular inspection is recommended, particularly for:

• Locking mechanisms
• Frame alignment
• Seal integrity
• Glazing condition

Components may wear or degrade, especially in coastal or high-humidity environments. Manufacturers often provide maintenance guidelines to preserve RC2 compliance over the window's lifecycle.

RC2 windows strike a practical balance between cost and security, offering reliable protection against common intrusion methods without significantly altering architectural aesthetics. Proper design, certified manufacturing, and professional installation are all essential for compliance. As security expectations evolve, RC2 remains a vital component of modern building envelopes—especially in areas prone to opportunistic crime.