SGI Composites, previously Sui Generis International, is celebrating its 30th anniversary, marking three decades of composite manufacturing, engineering and innovation from its base in Colchester.
Established in 1996 by Ron and Lizzy Stone, the business began as a small composite moulding company before developing into the engineered composite solutions provider it is today. Now part of Milbank Group, SGI Composites designs, manufactures and installs GRP solutions for customers across sectors including infrastructure, rail, energy and utilities, water, defence, marine and automotive.
The company recently marked the milestone with a 30th anniversary event at its Colchester headquarters, bringing together employees, customers, suppliers and guests to recognise the people and partnerships behind its development.
Over the past three decades, SGI Composites has continually adapted its capabilities in response to changing customer and industry requirements. Early work included specialist linings, flooring and bespoke tanks, with the business going on to deliver composite solutions for high-profile projects including St Pancras International, Ascot Racecourse, Frimley Park Hospital, Lloyds of London, Tesco and Network Rail.
This ability to diversify has seen SGI develop expertise across a broad range of applications, from access platforms, walkways and enclosures to containment systems, specialist linings and coatings, trench covers and bespoke manufactured components.
The business has also developed several specialist product ranges during its history. GeoMet began with a bespoke composite seating project before developing into a dedicated range, while Safe Tread established SGI’s presence in GRP anti-slip solutions. More recently, the Safe Spill range has expanded the company’s capabilities in GRP spill containment.
A significant milestone came in 2017 when the business joined Milbank Group, beginning the next phase of its development. Continued investment in its people, facilities, manufacturing processes and technical capabilities has since supported its move towards providing increasingly complex, engineered composite solutions.
In January 2026, Sui Generis International officially became SGI Composites, introducing a new identity designed to better reflect the breadth of its capabilities and its future direction.
Rita Cornwell, Managing Director of SGI Composites, said:
“Reaching 30 years is a significant milestone for SGI and a chance to recognise everyone who has contributed to the business along the way. Our success has been built on the knowledge and commitment of our team, together with the long-standing relationships we’ve developed with our customers and suppliers. While a lot has changed since 1996, that experience gives us a strong foundation for the future. We’re continuing to invest in our people, our capabilities and more sustainable ways of manufacturing, while developing the engineered composite solutions our customers need. It is an exciting time for SGI, and we are looking forward to building on those foundations as we begin the next chapter of the business.”
Long-serving employees have played an important role in that journey, with several members of the current team having spent decades with the company. Three employees alone have accumulated more than 75 years of service between them, reflecting the depth of experience and knowledge within the business. That experience, combined with continued investment in new skills, apprenticeships and the next generation of the SGI team, remains central to the company’s approach.
Sustainability has also become an increasingly important part of the company’s development. SGI has used rPET resin within its manufacturing since 2022, incorporating material derived from more than one million recycled plastic bottles each year and delivering a reduction of more than 45% in associated CO₂ emissions compared with conventional resin. The business also holds ISO 9001, ISO 14001 and ISO 45001 certifications.
Today, SGI works with customers from initial survey and technical design through to manufacture and installation, including the use of technologies such as LiDAR surveying and finite element analysis where required.
Recent projects demonstrate the scale and diversity of this work, from approximately 2,500 linear metres of rooftop GRP access infrastructure at Frimley Park Hospital to bespoke solutions for transport, utilities and industrial environments.
As SGI Composites enters its fourth decade, the focus is on continuing to develop its engineering capability, investing in its people and skills, improving manufacturing processes and supporting customers in new and existing markets.
