CE marking and EN 1090 for steel and aluminium structures
EN 1090 is the European standard for the execution of steel and aluminium structures, and its part 1 sets the conformity assessment that lets a load-bearing structural component carry the CE mark under the Construction Products Regulation, backed by a factory production control, an execution class and a Declaration of Performance. In short, it is the rule that makes a structural steel or aluminium component legally sellable and traceable in Europe. This guide explains EN 1090-1, the execution classes, the Declaration of Performance and the welding quality behind it. For the material side see our guide to EN 10204 material certificates.
What EN 1090 is
EN 1090 governs the execution, the making, of structural steelwork and aluminium structures. It comes in parts: EN 1090-1 covers the conformity assessment and CE marking of structural components, EN 1090-2 sets the technical requirements for steel structures, and EN 1090-3 does the same for aluminium. Together they define how a load-bearing component is designed for fabrication, made, welded, inspected and documented. Where a structure carries load, from a carport frame to a steel building, EN 1090 is the standard that says it was executed to a controlled, declared level rather than simply welded up.
EN 1090-1 and CE marking
EN 1090-1 is the part that connects a structure to the CE mark. It is a harmonised standard under the Construction Products Regulation, so a manufacturer that places a load-bearing steel or aluminium component on the European market must assess its conformity to EN 1090-1 and CE-mark it. The CE mark on a structural component is not a quality badge a maker awards itself; it is a declaration, under a regulated system, that the component’s performance has been assessed and documented. This is why a certified fabricator can supply into projects across Europe on a common, recognised basis.
Execution classes: EXC1 to EXC4
EN 1090 sets four execution classes, EXC1 to EXC4, each with a rising level of control, inspection and documentation. EXC1 covers the simplest, lowest-consequence work such as small storage buildings. EXC2 covers the great majority of ordinary structures, such as residential and commercial buildings, and applies by default where no class is specified. EXC3 and EXC4 cover higher-consequence structures, such as bridges and structures where a failure would be severe. The class is chosen from the consequence of failure and the type of loading, and it sets how rigorous the fabrication, welding and inspection must be.
Factory production control and the notified body
Behind a CE-marked component is a factory production control, or FPC. This is the documented system by which a fabricator controls its production so that what leaves the works has the declared performance, covering everything from incoming material and its certificates to welding, inspection and records. For structural components, the FPC has to be assessed and certified by a third-party notified body before the manufacturer can issue a Declaration of Performance and CE-mark its output. This external check is what gives EN 1090 CE marking its credibility: the system is verified by an independent body, not just claimed.
The Declaration of Performance
The Declaration of Performance, or DoP, is the document by which the manufacturer takes responsibility for a component’s declared performance. It carries a unique product identification code, a reference to the harmonised standard EN 1090-1, the execution class applied, the name and certificate number of the notified body, and the declared characteristics of the component. The DoP is issued with the CE-marked component and is the buyer’s proof that the structure was assessed under the regulated system. Where an EN 10204 certificate proves the input material, the DoP covers the finished structural component and its execution.
Welding quality: ISO 3834
Welding is where a structure is made or lost, so EN 1090 ties the execution classes to a welding quality standard, ISO 3834. The higher the execution class, the more comprehensive the welding quality requirements: EXC2 work is welded under ISO 3834-2, the comprehensive level, with qualified welding procedures, qualified welders and the records to prove them. This is a separate, welding-specific discipline from the general production control, and it is why a certified structure is more than a good-looking weld: the procedure, the welder and the inspection are all documented behind it.
Steel and aluminium: EN 1090-2 and 1090-3
The technical requirements differ by metal, so EN 1090 splits them. EN 1090-2 sets the execution requirements for steel structures, covering the grades, the fabrication, the welding, the tolerances and the corrosion protection. EN 1090-3 does the same for aluminium structures, which behave differently in welding and in service. A fabricator working in both metals, as many do on carports, canopies and mixed structures, works to both parts as the job requires. The shared part 1 then carries the conformity assessment and CE marking across both, so a mixed structure is documented on one basis.
What CE marking means for the buyer
For a buyer or specifier, the CE mark and its DoP answer a simple question: was this load-bearing component made to a controlled, declared and independently assessed standard. It confirms the execution class, points to the notified body that certified the production control, and states the declared characteristics, so the component can be accepted into a project and its paperwork filed against the design. Specifying EN 1090 with the right execution class from the outset, rather than discovering it is needed at handover, is what keeps a structural project compliant and its sign-off straightforward.
Who needs CE marking, and when
CE marking under EN 1090 applies to load-bearing structural components placed on the European market, so it is triggered by the structural role of the part, not by the material alone. A fabricated steel or aluminium frame that carries load, a carport, a canopy, a PV mounting structure, a steel building, falls within it and must be assessed, CE-marked and issued with a Declaration of Performance. Raw material that a customer will fabricate themselves is supplied with its material certificate instead, and the fabricator who turns it into a structure carries the EN 1090 obligation. Knowing which side of that line a supply sits on decides which documents it needs.
What the CE mark does not mean
The CE mark on a structural component is often misread, so it helps to be clear on what it is not. It is not a general company quality badge that a maker awards itself; it is a regulated, product-specific declaration assessed against EN 1090-1 and backed by a notified body. It is not the same as a material certificate: the CE mark and its Declaration of Performance cover the finished structure and its execution, while an EN 10204 certificate covers the input metal. And it is not optional decoration on a load-bearing component sold in Europe; it is a legal requirement under the Construction Products Regulation. Reading it correctly keeps a project’s compliance honest.
Inspection and records in EN 1090
Much of EN 1090 is about proving, not just doing. The execution class sets how much inspection and documentation a structure needs, and at EXC2 that means records that tie the finished component back to its inputs and its execution: the material certificates for the steel and aluminium, the qualified welding procedures and welder qualifications, and the inspection results. These records are what stand behind the Declaration of Performance, so a certified structure can be audited after the fact rather than taken on trust. This is the same traceability logic as a material certificate, applied to the whole fabricated component instead of the raw metal. It is also why specifying the execution class early matters: a structure built without the EXC2 records in place cannot simply have them added at handover, any more than metal can be certified after it has lost its traceability.
EN 1090 and material certificates together
EN 1090 and EN 10204 are two documents that answer different questions on the same job. An EN 10204 certificate, usually a 3.1, proves the input steel or aluminium meets its grade and is traceable by its heat number. The EN 1090 Declaration of Performance covers the finished load-bearing component and how it was executed. A certified fabricator builds a CE-marked structure from certified material, so the two trails join: the material certificate feeds into the structural declaration. For the material document see our guide to EN 10204 material certificates.
EN 1090 at ULAMEX
ULAMEX brings 38 years of experience in European metals trading and has been in the steel and aluminium wholesale industry since 1988, manufacturing its own load-bearing structures under EN 1090-1 EXC2 and welding them to ISO 3834-2.
| Element | Detail |
|---|---|
| Standard | EN 1090-1 for CE marking; EN 1090-2 steel, EN 1090-3 aluminium |
| Execution class | EXC2 (the default for ordinary structures) |
| Welding quality | ISO 3834-2, the comprehensive level for EXC2 |
| Structural products | Carport, PV mounting and fencing structures, CE-marked with a Declaration of Performance |
| Material | Certified steel and aluminium with EN 10204 3.1 on request |
ULAMEX CE-marks its own carport, PV mounting and fencing structures under EN 1090-1 EXC2 with a Declaration of Performance, and supplies certified material with EN 10204 3.1 certificates for others to fabricate. Send the structure or the material and the requirements your project sets, and ULAMEX will return a non-binding quotation with lead time and availability. See our supply capabilities, our PV mounting systems and structural steel guides, or the EN 10204 material certificates guide. Contact the export desk at [email protected] or +48 504 424 761.
Frequently asked questions
What is EN 1090?
EN 1090 is the European standard for the execution of steel and aluminium structures. EN 1090-1 covers the conformity assessment and CE marking of structural components, EN 1090-2 sets the technical requirements for steel structures and EN 1090-3 for aluminium. It is the standard that makes a load-bearing structural component legally sellable and traceable in Europe.
What does CE marking under EN 1090 mean?
It means a load-bearing steel or aluminium component has been assessed for conformity to EN 1090-1 under the Construction Products Regulation, with its factory production control certified by a notified body, and issued with a Declaration of Performance. The CE mark is a regulated declaration of assessed performance, not a self-awarded quality badge.
What are the execution classes EXC1 to EXC4?
They are four rising levels of control, inspection and documentation. EXC1 is for the simplest work such as small storage buildings, EXC2 covers most ordinary structures and applies by default if none is specified, and EXC3 and EXC4 cover higher-consequence structures such as bridges. The class is chosen from the consequence of failure and the loading.
What is a Declaration of Performance?
The Declaration of Performance, or DoP, is the document by which the manufacturer takes responsibility for a component’s declared performance. It carries a unique product code, a reference to EN 1090-1, the execution class, the notified body’s name and certificate number, and the declared characteristics. It is issued with the CE-marked component.
How does EN 1090 relate to material certificates?
They are different documents. An EN 10204 certificate, usually a 3.1, proves the input steel or aluminium meets its grade and is traceable. The EN 1090 Declaration of Performance covers the finished load-bearing component and its execution. A certified fabricator builds a CE-marked structure from certified material, so the two trails join.
Does ULAMEX work to EN 1090?
Yes. ULAMEX manufactures its own carport, PV mounting and fencing structures under EN 1090-1 EXC2, welds them to ISO 3834-2, and CE-marks them with a Declaration of Performance. It also supplies certified steel and aluminium with EN 10204 3.1 certificates for others to fabricate. Send the requirements your project sets for a quotation.