The new Belfast Grand Central Station stands as one of the most significant public infrastructure projects in Northern Ireland’s history, a transformative transport hub designed to bring together rail, bus, and active travel under one dramatic roofscape.
Conceived as a symbol of connectivity and civic pride, the £300 million development is redefining Belfast’s skyline.
At the heart of this architectural achievement lies Kalzip’s aluminium standing seam roof system, providing the performance, flexibility, and aesthetic precision required for such a landmark project.
The project team behind the station reflects a collaborative partnership of industry leaders: RPP Architects, John McAslan + Partners and Arup provided architectural and engineering design expertise, while the Farrans Sacyr Joint Venture (FSJV) delivered the complex construction works. Thornton Roofing (Ireland) Ltd, a long-established Kalzip specialist, was appointed to design, supply, and install the roofing and soffit systems, a scope that encompassed more than 12,000m² of Kalzip standing seam roofing across the station’s multiple structures.
Adam Thornton from Thornton Roofing (Ireland), said: “The decision to use Kalzip was driven by the system’s proven ability to deliver both architectural freedom and long-term technical reliability. For a project of this complexity, the design team required a roofing solution capable of meeting exacting performance standards, including stringent fire, blast, and weathering criteria, while maintaining visual consistency across an expansive and geometrically varied roofscape. Kalzip’s lightweight, non-penetrative standing seam system provided the ideal balance, offering the durability of aluminium with the flexibility to accommodate the dynamic profile and elevations that define the station’s form.”
The roofscape itself is a defining architectural element of the new transport interchange. Comprising multiple roof zones, each tailored to specific building functions, the design evokes both movement and openness, qualities central to the project’s identity as a gateway to the city. Kalzip’s precision-engineered profiles enabled these complex geometries to be realised seamlessly, ensuring smooth transitions and an uninterrupted visual rhythm across the building envelope.
Working closely with Thornton Roofing and the design team, Kalzip’s technical specialists provided detailed support throughout the design and delivery process. The project required extensive coordination to integrate concealed insulated gutter systems, bespoke support bracketry, and enhanced fixing assemblies to meet the site’s blast resistance requirements. The flexibility of the Kalzip system allowed these performance upgrades to be incorporated without compromising appearance or design intent, a testament to the system’s adaptability under demanding technical conditions.
A further dimension of Thornton’s work involved the development of a custom soffit system, designed and manufactured in-house to complement the Kalzip roof. The result is the station’s striking gold-finished soffit, which defines the main entrance and contrasts beautifully with the refined metallic tones of the roof above. This integration of Kalzip’s aluminium technology with bespoke detailing exemplifies how material innovation and craftsmanship can elevate large-scale infrastructure beyond functionality to architectural expression.
From the earliest design stages, collaboration between the project stakeholders was central to achieving success. The coordination between Kalzip, Thornton Roofing, and Arup’s structural and blast engineering teams ensured that every component of the system performed under the most rigorous conditions. These efforts were supported by continuous dialogue with FSJV’s construction management team, ensuring that installation sequencing, material logistics, and on-site safety standards met the project’s strict requirements.
Trevor Smyth, National Sales Manager from Kalzip, said: “The complexity of the site, located within Belfast’s active city centre transport corridor, demanded meticulous planning. Kalzip delivered aluminium coils to site and the standing seam sheets were profiled at eaves level, and combined with Thornton Roofing’s expert installation, this helped mitigate site constraints and ensured the works progressed efficiently within tight programme windows. Despite challenging conditions and technical demands, the roofing package was delivered to exceptional quality standards, earning widespread recognition across the industry.”
That recognition culminated at the 2025 Kalzip TeamKal Awards, where the Belfast Grand Central Station project achieved Gold in the Contractors’ Choice Award and Silver in the Best Project (over 1500m²) category. These accolades celebrated not only Thornton Roofing’s outstanding delivery but also the success of Kalzip’s system in fulfilling the architectural and performance vision of the wider team. The project serves as a model for how collaboration between manufacturer, installer, and design professionals can push the boundaries of what is possible in metal roofing and façade engineering.
For Kalzip, the Belfast Grand Central Station reinforces the company’s position as a leading global supplier of advanced building envelope solutions. The system’s performance, adaptability, and aesthetic precision have made it the preferred choice for complex public architecture across Europe, from transport hubs to universities and cultural landmarks. Its recyclable aluminium composition supports the project’s sustainability ambitions, contributing to long service life and minimal maintenance requirements.
The new Belfast Grand Central Station will accommodate up to 20 million passengers annually, creating a seamless link between local and regional transport services. Beyond its functionality, the building will stand as a symbol of Belfast’s regeneration and ambition. Kalzip’s contribution, a roof that embodies both engineering excellence and architectural beauty, will play a lasting role in defining the character of this civic landmark.
The success of the Belfast Grand Central Station project demonstrates how Kalzip systems continue to enable innovation in contemporary architecture. By combining technical performance with design versatility and collaborative expertise, Kalzip has helped to deliver a structure that is both functionally advanced and visually iconic, a new benchmark for transport infrastructure in the UK and beyond.
