In an extraordinary blend of cutting-edge technology and heritage sensitivity, South Wales-based security specialists Plexus FS have successfully installed a state-of-the-art intruder alarm system at the iconic Margam Castle — a Grade I listed gothic mansion with a rich, complex past and a very delicate present. 

Working through partners BFL Engineering Services LTD, the project presented challenges ranging from bat conservation to strict no-drill protocols; however, for Plexus FS, it was another opportunity to prove why they’re the trusted choice for securing the region’s most treasured landmarks.

Protecting a Castle – and Its Creatures

Perched within Margam Country Park and visited by thousands each year, Margam Castle is no ordinary property. 

Built in the 1830s by Christopher Rice Mansel Talbot, one of the wealthiest landowners in Wales, the gothic-style building has seen centuries of history, from Victorian grandeur to devastating fire damage in the 1970s. Now a jewel in Neath Port Talbot’s tourism crown, it’s a public asset – and a security challenge.

Plexus FS was called in to install an intruder alarm system that wouldn’t just protect the building and its artefacts, but also safeguard its hidden residents – a colony of endangered bats.

“There was no room for error here,” said Gavin Heard of Plexus FS. “We couldn’t drill into any surfaces due to the castle’s Grade I listing and the strict ecological protections in place. That meant all wiring had to be installed externally and with complete discretion. It’s not the norm for us – but adapting is part of our strength.”

Precision Tech with a Light Footprint

The solution was an expertly installed network of dual-lens passive infrared (PIR) and microwave motion detectors, fitted high into corners of key interior spaces. 

These sensors detect infrared heat, flagging even the slightest human presence, while remaining invisible to the bat population whose roosting areas were mapped out in advance.

The detectors include LED indicators – red and blue – to show system status and movement, enabling real-time verification without intruding on the building’s historic integrity. 

Strategic placement was key. 

Maximising coverage while avoiding disruption to wildlife required night work and strict adherence to environmental guidelines. “We carried out much of the installation work during daylight hours to avoid disturbing the bats’ nocturnal patterns,” explained Gavin, “and had the assistance of a bat specialist who advised where we could and couldn’t go without them checking the area first.”

Securing the South Wales Heritage Landscape

This is just the latest in a series of successful installations by Plexus FS at heritage and listed sites across Wales and the wider UK. 

From medieval castles and Georgian manor houses to libraries, universities and civic buildings, the firm is building a reputation for delivering 21st-century security with 19th-century care.

“Heritage sites like Margam Castle demand more than just technical know-how – they require a deep respect for architecture, biodiversity, and legacy,” said Gavin Heard. “We’re proud to be the go-to provider for organisations who need security without compromise.”

While not every business operates in a castle, many face their own unique security challenges – whether it’s outdated infrastructure, listed status, or sensitive environments. Plexus FS specialises in finding solutions where others see roadblocks.

Their services include:

  • Intruder alarm systems
  • CCTV surveillance
  • Access control
  • Fire safety systems
  • 24/7 monitoring and response

Each installation is tailored to the building and the business it serves, and as Margam Castle proves, no location is too complex or sensitive for its experienced team.

A Message to Facilities and Health & Safety Managers

If you’re responsible for securing a business or property in South Wales – whether it’s a school, shopfront, warehouse or historic building – Plexus FS offers peace of mind, professionalism, and proven results.

As Gavin Heard concludes:

“We’re not just installing alarms. We’re protecting people, heritage, and futures. That’s a responsibility we take seriously – whether the building’s brand new or 200 years old.”