CE marking and EN 14351 for windows
A CE-marked window is a declaration that the unit meets the harmonised standard for its intended use: EN 14351-1 for external windows and doors. The mark is not a badge added at the end — it is a Declaration of Performance tied to a set of tested characteristics and a factory production control system, and it travels with the unit as the document a European specifier, or a market that recognises the standard, asks for.
What EN 14351-1 actually covers
The standard names the characteristics of an external window or door. Three always apply — watertightness, air permeability and resistance to wind load. The rest are optional and depend on the project: thermal transmittance (U-value), solar factor, sound reduction, impact resistance and the load-bearing of safety devices, among others. The CE mark declares performance against those characteristics, not a single pass-or-fail grade.
The Declaration of Performance
The DoP is the document: it names the product and the manufacturer, lists the harmonised standard and the tested characteristics with their values, and references the assessment system the product falls under. It is generated from the tested characteristics of the configured unit. The mark is only meaningful attached to a DoP that matches the product shipped, which is why the configuration is locked before the paperwork is issued.
The other route: a project-based spec
Outside the EU, the CE mark is often not the entry document. The specification there is the project standard and the test report: AAMA and NFRC in the US, AS 2047 and AS 1170.2 in Australia, UKCA in the UK post-Brexit, the local code of record elsewhere. The drawing office keeps both columns — the EN 14351 characteristic table and the destination-market test — so one order ships to both without re-testing.
How it reads on the schedule
- Name the standard and the characteristics that matter to the project — watertightness and wind load always; U-value, acoustic and impact where they apply.
- State the destination market, because the recognition route differs: EU and EEA on EN 14351 and the CE mark, the UK on UKCA, others on the project test.
- Ask for the test report and, where the standard is the route, the Declaration of Performance for the configured unit — not a general capability statement.
Questions
In the EU and EEA, for external windows and doors covered by the harmonised standard, the CE mark with a DoP is the route to place them on the market. Other markets have their own recognition route.