If you commission structural steelwork in the UK, you will almost certainly have come across the term BS EN 1090. It appears in tender requirements, client specifications and contractor accreditation lists across the construction and engineering sectors. Yet for many clients, the detail behind the standard remains unclear. What does BS EN 1090 require? Why does it exist? And why should it matter when you are choosing a structural steel contractor in Lincolnshire, Yorkshire or the East Midlands?
What Is BS EN 1090?
BS EN 1090 is the European standard for the fabrication and erection of structural steel and aluminium components. It was introduced to harmonise structural steelwork standards across Europe and became mandatory in the UK in 2012. The standard applies to any steel structure that forms part of a building or civil engineering works, covering everything from large industrial frames and platforms to walkways, staircases, pipe racks and supporting structures.
The standard has two key parts. BS EN 1090-1 deals with the conformity assessment requirements, which govern how a manufacturer or fabricator demonstrates compliance. BS EN 1090-2 sets out the technical requirements for the fabrication and erection of steel structures. Together, they establish a comprehensive framework covering materials, welding, tolerances, surface treatment, testing and documentation.
Execution Classes: What They Mean in Practice
BS EN 1090 defines four execution classes, known as EXC1 to EXC4, which reflect the consequence of failure and the complexity of the structure. Higher execution classes demand more stringent fabrication controls, welding requirements and inspection regimes. In broad terms:
- EXC1 applies to relatively simple structures with low consequence of failure.
- EXC2 covers most standard structural steel applications in buildings and general construction.
For the industries Site Service Engineering serves, including steel manufacturing, petrochemicals, oil and gas and power generation, these requirements are common. This places significant demands on our fabrication processes, weld inspection procedures and quality management systems.
Why Does BS EN 1090 Matter to Clients?
Choosing a BS EN 1090 certified contractor gives clients a verifiable assurance that the structural steelwork on their project has been fabricated and erected in accordance with a recognised, independently audited standard. It means that welding procedures are qualified, welders are certified, materials are traceable and inspections are documented. In short, it removes uncertainty from the process and provides a clear paper trail should any question ever arise about the integrity of the structure.
For clients in high-hazard industries, this is not simply a commercial preference; it is often a contractual and regulatory requirement. Many principal contractors and end-user clients will not accept steelwork from fabricators who cannot demonstrate BS EN 1090 certification.
Site Service Engineering and BS EN 1090
Site Service Engineering holds BS EN 1090 certification, independently audited and maintained through our accreditation body ISOQAR. Our most recent re-audit was completed with a perfect record, reflecting the rigour of our quality management systems and the skill of our fabrication and erection teams. We work to BS EN 1090 requirements on structural steel projects throughout Lincolnshire, Yorkshire and the East Midlands, giving our clients the confidence that every piece of steelwork we produce meets the standard.
If you are planning a structural steel project and want to work with a contractor whose BS EN 1090 credentials are fully up to date, get in touch with Site Service Engineering today.