High Security Fencing & Security Rated Systems

LPCB-Certified High Security Fencing: Perimeter Protection You Can Evidence

A fence that only looks strong is a liability, not a control. If your site holds critical infrastructure, sensitive data, or high-value assets, your perimeter needs to do more than deter, it needs to have proven, tested, evidenced resistance to attack.

At Alexandra Security, we manufacture and supply security rated fencing systems that go beyond standard perimeter fencing. Every system in our Protek Elite range is independently tested by the Building Research Establishment (BRE) and certified by the Loss Prevention Certification Board (LPCB) to LPS 1175, the UK’s leading standard for forced-entry resistance. That certification is your evidence: verifiable, third-party proof that your perimeter will hold against real-world intrusion attempts, not just a manufacturer’s claim.

Why Choose Security Rated Fencing?

Standard fencing might look robust, but without independent testing there is no way to know how it performs under attack. LPCB-certified fencing removes that uncertainty. Each system is tested against defined tool kits for a specified minimum working time, so you know exactly what level of protection you are specifying — and can prove it to insurers, regulators, and auditors.

LPS 1175 is now in its Issue 8.2 revision, which uses a letter-and-number classification (tool category and minimum delay in minutes) alongside the legacy SR ratings that many specifiers still reference. The four ratings most commonly specified for perimeter fencing are:

SR1 / A1 High Security Fencing

Resists opportunistic attacks using basic hand tools; screwdrivers, pliers, knives, for a minimum working time of 1 minute. Suited to sites where the priority is deterring casual intrusion and supporting early detection.

SR2 / B3 High Security Fencing

Resists more determined attacks using higher mechanical-advantage tools; bolt cutters, claw hammers, drills, for a minimum working time of 3 minutes. Suited to sites facing a higher threat level or requiring a longer delay to support response times.

SR3 / C5 High Security Fencing

Resists deliberate, sustained forced entry using more powerful tools including short axes, chisels, crowbars, and battery-powered tools, for a minimum working time of 5 minutes. Typically specified where the threat assessment goes beyond opportunistic crime, such as higher-risk CNI and government sites.

SR4 / D10 High Security Fencing

Resists determined, well-equipped attacks, including power tools such as grinders and reciprocating saws, for a minimum working time of 10 minutes. Reserved for the highest-risk perimeters, including critical plant areas and sites hosting government or defence workloads.

Where High Security Fencing is Essential

Our security rated systems are specified across some of the UK’s most sensitive and highest-value sites, including:

Utilities and Energy Facilities

Water and wastewater sites, electricity substations and generation, solar farms, and battery energy storage systems (BESS)

Data Centres and Data Centre Security Perimeters

Protecting server halls and critical plant from physical intrusion and opportunistic crime

Transport and Logistics

Including high-speed rail and freight infrastructure

Defence, Government, & CNI Sites

Where threats and potential risk are critically important.

Commercial and Industrial Estates

Often have elevated security or insurance requirements

Across these sectors, fencing has to satisfy more than a site manager’s judgement — it has to satisfy insurers, regulators, and increasingly the planning process itself. LPCB-approved fencing gives you evidence-backed protection that stands up to scrutiny from all three.