Free guide · For steel and aluminium fabricators
A plain-English guide to BS EN 1090: what it is, whether you need it, what EXC1 and EXC2 mean and what a certification body will expect to see. Written by a former lead auditor who has audited BS EN 1090 businesses.
What is BS EN 1090?
BS EN 1090 is the standard for fabricating structural steel and aluminium components. Part 1 covers how components are assessed and marked, Part 2 sets the technical requirements for steel and Part 3 for aluminium.
Under the Construction Products Regulation, structural components placed on the market must be UKCA marked for Great Britain, or CE marked for the EU and Northern Ireland. To do that, a fabricator needs a Factory Production Control (FPC) system that has been assessed and certified by an approved body (UK) or notified body (EU). The fabricator then issues a Declaration of Performance for its components.
Do I need it?
If you fabricate structural steel or aluminium components such as beams, columns, frames, trusses, staircases, mezzanines or canopies, and supply them to customers, you will generally need BS EN 1090 certification. Many main contractors will not place structural work without it.
Whether a particular job is in scope can depend on how the work is supplied and installed. If you are unsure, get in touch and we'll talk it through.
Execution classes explained
Every structure is built to an execution class, from EXC1 to EXC4. The higher the class, the more demanding the requirements. The class is set by the designer or structural engineer, not the fabricator. If none is specified, BS EN 1090-2 says EXC2 applies.
| Class | Typical use | Welding quality level |
|---|---|---|
| EXC1 | Low-consequence structures, such as some agricultural buildings | Elementary (ISO 3834-4) |
| EXC2 | Most buildings and general structural steelwork | Standard (ISO 3834-3), with a welding coordinator |
| EXC3 | More demanding structures, such as stadia and some bridges | Comprehensive (ISO 3834-2) |
| EXC4 | Special structures where failure would have extreme consequences | Comprehensive (ISO 3834-2) |
SBMS supports fabricators working to EXC1 and EXC2.
What an auditor will expect to see
- A documented FPC system that matches how your workshop really operates
- Contract review, so you know the execution class and requirements of every job
- Material traceability from mill certificate to finished component
- Qualified welding procedures and qualified welders, with in-date records
- Welding coordination for EXC2 work
- Inspection and test plans, with records for each job
- Calibrated equipment, nonconformance records and corrective actions
- Correct Declarations of Performance and marking
The route to certification
- Gap analysisCompare your current workshop practice with BS EN 1090 and identify what's missing.
- FPC systemWrite the manual, procedures and records, and arrange welding procedure and welder qualification testing.
- Run it on live jobsBuild up records on real work so there's evidence for the auditor to see.
- Internal auditAudit the system and a live job from order to delivery before the assessment.
- Initial assessmentThe approved body inspects your factory and FPC system, then issues your certificate once findings are closed.
- SurveillanceRegular surveillance visits keep your certification in place.
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