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X-Span

Structural glazing creates innovative daylighting opportunities for architectural projects with unique geometries and demanding specifications.

Suitable for:

  • Roof pitches from 5° to 90°, including flat, low-pitch and vertical applications
  • Large-span rooflights up to 7 m wide and unlimited length in modular bays
  • Complex geometries such as ridgelights, pyramids, domes, barrel vaults and canopies
  • High-humidity environments like swimming pools and sports halls, thanks to built-in condensation channels
Aerial view of building with metal roof and parking area.
X-Span structural glazing delivers large-span rooflights with exceptional design freedom
Building with metal roof and circular skylight, stone walls visible.
X-Span enables complex glazed forms tailored to bespoke project requirements
Circular glass dome ceiling with geometric pattern and blue sky view.
Engineered aluminium framing and high-performance glazing combine in X-Span to provide strength, transparency and long-term weather resistance
Metal roof with skylights, surrounded by trees and parked cars.
Engineered aluminium framing and high-performance glazing combine in X-Span to provide strength, transparency and long-term weather resistance
Glass pyramid roof reflecting cloudy sky, part of modern building.
A versatile glazing system designed for bespoke roof and façade applications
Interior space with triangular glass roof panels and metal framework.
X-Span enables self-supporting glazed structures, achieving large spans with minimal external support and uninterrupted architectural clarity

Product details

The X-Span system is a versatile structural glazing solution designed to create striking daylight features in both standard and bespoke applications. Fully weather tested for installation from 5° to 90°, it can form rooflights, ridgelights, pyramids, domes, barrel vaults and canopies. With a wide range of glazing options, integrated comfort and smoke ventilation, and proven performance values, X-Span is an adaptable daylighting system for complex architectural projects.

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Two rooftop skylights on a flat roof with cloudy sky.
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Flat roof with skylight panels, modern design.
XLS
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Frequently asked questions

What is the X-Span Structural Glazing System and what makes it ideal for commercial buildings?

X-Span is a sophisticated stick-glazing system that uses interchangeable aluminium profiles to create made-to-measure daylight solutions for both glass roofs and facades. The system offers almost unlimited design freedom, allowing architects and building owners to create individual, creative and tailor-made daylight and ventilation solutions with excellent physical building properties.

This glass roof system is particularly valuable for commercial building owners seeking large-scale, architecturally striking rooflight solutions that provide optimal natural light while maintaining structural integrity.

How does the X-Span system handle structural loads and what are the size limitations?

The X-Span structural glass roof is specifically engineered to manage substantial structural loads, making it well-suited for large-scale commercial glazing applications. Its aluminium profiles feature a 60 mm mullion and transom width, with depths ranging from 35 mm to 170 mm depending on the span and load conditions. These profiles are designed to withstand various forces, including glazed imposed loads, wind pressure, and snow accumulation. Each installation is supported by detailed static calculations carried out by engineering specialists to ensure safety and performance tailored to the specific building project.

In terms of size limitations, the system can span up to 10 meters unsupported when self-supporting, while virtually any size can be achieved when fixed to a supporting structure. This combination of engineered load-bearing capacity and flexible sizing enables the X-Span system to deliver expansive glazed solutions without compromising structural integrity.

What ventilation and smoke management options do you offer with the X-Span installation?

The X-Span system offers integrated solutions designed to meet both everyday comfort and critical safety requirements. For smoke ventilation, it features bottom-hung or side-hung openings that comply with EN 12101-2 standards, ensuring effective smoke and heat exhaust during emergencies. In addition to emergency use, X-Span supports comfort ventilation by allowing natural air circulation through customizable openings that can be tailored to a building’s specific needs. These ventilating openings are seamlessly incorporated into the glazing design, maintaining both aesthetic consistency and structural integrity. This dual capability makes X-Span a practical choice for commercial buildings where occupant comfort and regulatory compliance for smoke evacuation are equally important.

What kind of support and guarantees do you provide for commercial projects?

We provide extensive support for commercial projects, offering a complete, end-to-end solution that spans design, manufacturing, installation, and long-term performance guarantees. From the outset, our customers benefit from expert consultation and tailored design assistance, followed by professional manufacturing and installation by trained specialists. This integrated approach ensures that both the product and the installation are fully covered under a comprehensive guarantee.

A key feature of our X-Span offering is its 20-year guarantee on the entire structural glazing system, backed by professional engineering calculations and strict quality control at every stage. Technical features such as excellent sealing for low-pitch roofs (minimum 5°), reliable two-level drainage, EPDM gaskets, and concealed fixings further reinforce long-term durability. Aluminium pressure plates and cover caps provide a desirable finish.

To streamline project execution, X-Span also offers a single point of contact for design, supply, and installation, supported by coordinated project management and technical guidance for architects, installers, and building owners. This all-encompassing support model minimizes project risks and ensures consistent, high-performance results over the long term.

How does X-Span compare to VELUX Glazing Panels (formerly Vitral A74 and A98 Roof Glazing) in terms of design flexibility and installation?

X-Span and VELUX Glazing Panels (formerly Vitral A74 and A98) both provide bespoke glazing solutions for commercial buildings, but they differ considerably in design flexibility and installation. X-Span is a stick system built on-site with interchangeable aluminium mullions and transoms, allowing for virtually unlimited opening widths, making it ideal for large-scale projects with complex geometries and demanding structural requirements.

In contrast, VELUX Glazing Panels use a prefabricated, panel-based approach, offering slim and shallow profiles that maximize daylight and suit medium-sized applications, such as refurbishments and pitched or flat roof installations. While X-Span emphasizes structural freedom and scalability, VELUX Glazing Panels focus on ease of installation, visual minimalism, and integrated ventilation options, with individual panel sizes limited to 2–3m².

Thermal performance is strong in both systems, with options for both double and triple glazing to be utilised. Overall, X-Span offers greater design freedom for large and complex projects, whereas VELUX Glazing Panels are optimized for streamlined installation and aesthetic integration in smaller to medium-scale applications.

What does the installation process involve, and what support is provided during installation?

We provide design, manufacture, and installation as a complete package. The stick system consists of vertical mullions and horizontal transoms that are assembled on site. This on-site assembly approach allows for precise fitting to the specific building requirements and structural conditions.

Component assembly:

  • Profile system: The mullions and transoms have a 60 mm profile width with heights ranging from 35 mm to 170mm
  • Sealing system: Mullions and transoms are fitted with EPDM gaskets for weather sealing
  • Glazing installation: Aluminium pressure plates and cover caps with EPDM gaskets retain the insulating glass units in place via concealed fixings
  • Drainage: For low pitched rooflights, a silicone sealed glass-to-glass joint can be used on the transoms to aid with water runoff

Professional installation service: Installation is carried out by trained specialists familiar with the system requirements.

Has X-Span been used as part of a renovation in listed or heritage buildings where appearance and integration were critical?

Yes. The X-Span system has been successfully implemented in the renovation of the listed Bute Building at Cardiff University. Due to structural requirements, a particularly lightweight glazing was used. The installation, an approximately 20-metre-long glass roof, provided improved daylight, insulation, and design flexibility while meeting strict heritage preservation requirements. This demonstrates the glazing systems suitability for sensitive conservation projects where seamless integration and aesthetics are essential.