HR DD11 Perforated Sheet

This material combines a hot-rolled, heavy-gauge (4mm) mild steel plate with DD11-grade ductility and a precision security perforation pattern (as per EN 10111 standard). 

While standard architectural perforated sheet metal typically relies on thin 1mm–2mm gauges, this 4mm hot-rolled sheet provides vastly improved resilience against blunt force and leveraging attacks, making it capable of serving as a physical barrier in high-vulnerability environments—such as cell door vision panels, custodial ventilation grilles, radiator covers, and secure ducting. Available for immediate delivery at a highly competitive price.

Prison Specification

In institutional environments (such as Ministry of Justice (MoJ) facilities, police custody suites, and secure psychiatric units), material requirements extend beyond simple strength:

• Contraband & Weapon Prevention: Small perforation sizes prohibit passing concealed items—such as razor blades, drugs, or makeshift tools—between secure and non-secure zones.
• Anti-Ligature Apertures: The hole diameters and pitch are tightly restricted. This prevents string, shoelaces, or contraband wire from being threaded through the openings to anchor a ligature.
• Deburred & Smooth Edge Finish: The specification requires complete removal of punch flash and sharp internal edges. Perforations must be smooth to ensure inmates cannot use internal hole margins to shred fabric or cause self-harm.
• Heavy 4mm Wall Mass: Standard perforated sheets bow or collapse when levered with smuggled objects or struck repeatedly. The 4mm thickness ensures structural rigidity across larger frame openings.