Ask ten suppliers in Foshan about CE marking and most will tell you they are "CE certified". That sentence is the first sign of a problem, and it is usually not a lie — it is a misunderstanding that has been copied from catalogue to catalogue for twenty years.
There is no such thing as a CE certificate held by a supplier. Understanding what CE marking actually is changes what you ask for, what you compare, and who you can hold responsible when something is wrong.
1. What CE marking actually is
Windows and doors placed on the EU market are covered by the Construction Products Regulation (CPR, EU 305/2011). The harmonised standard for windows and external pedestrian doorsets is EN 14351-1.
Under that system:
- The manufacturer draws up a Declaration of Performance (DoP) and signs it. The manufacturer's name and address are on it.
- The manufacturer affixes the CE marking. Nobody issues it to them.
- A notified body carries out initial type testing (ITT) — the test report carries the notified body's four-digit number.
- Most windows are placed under AVCP system 3: the notified body does the testing, the manufacturer does the declaration. Fire and smoke doorsets go under system 1, where the notified body is involved continuously and does issue a certificate.
The practical consequences are direct:
| You ask for | What it proves |
|---|---|
| The DoP, with the manufacturer named | Who is legally responsible for the declared performance |
| The ITT report and the notified body's 4-digit number | That the declared performance was actually tested by an accredited body |
| The CE mark on the product or its label | That the marking requirement was followed |
| Nothing | What a trading company can give you — a copy of somebody else's document |
This is where "we are CE certified" falls apart. A trading company, an agent, or a supplier cannot hold CE marking on a product it does not manufacture. If the DoP names a factory, that factory is the responsible party — and if the company quoting you is not that factory, you have found the gap.
2. What the declaration has to state
CE marking is not a quality grade. It is a declaration of measured performance in a defined class. For windows, the characteristics that matter most in practice:
| Characteristic | Test standard | Typical scale |
|---|---|---|
| Air permeability | EN 12207 | Classes 1–4 (4 = tightest) |
| Watertightness | EN 12208 | Classes 1A–9A (9A = driven rain) |
| Resistance to wind load | EN 12210 | Classes 1–5, plus deflection class A / B / C |
| Thermal transmittance | EN ISO 10077-1 / -2 | Uw value in W/m²K |
| Sound insulation | EN ISO 717-1 | Rw (C; Ctr) in dB |
| Reaction to fire | EN 13501-1 | Where the application requires it |
| Burglary resistance | EN 1627–1630 | RC1–RC6 (usually RC2 / RC3) |
| Load-bearing capacity of safety devices | EN 14351-1 | Required for devices used in cleaning or maintenance |
| Dangerous substances | — | Declaration where relevant |
Two points worth holding on to. First, EN 12207, EN 12208 and EN 12210 are the three that buyers actually compare, because they are the ones that decide whether a window survives a real building in a real climate. Second, burglary resistance is optional — it appears only when the manufacturer declares it, and it is asked for most often in Germany, the Netherlands and Austria.
3. The mistake: comparing "CE" instead of comparing classes
Every window we are discussing here can carry a CE mark. That tells you the paperwork exists. It tells you nothing about the window.
A window declared at watertightness class 2 and a window declared at class 9A both show the same CE marking. One is built for sheltered sites. The other is built for wind-driven rain on an exposed facade. The mark does not distinguish them; the class does.
So the useful sentence in a specification is not "CE marked". It is:
Watertightness to EN 12208 class 9A, wind load to EN 12210 class 4 with deflection class C, Uw ≤ 1.4 W/m²K.
Write that, and the quotes you receive are suddenly comparable — and the factories that cannot reach those numbers stop quoting.
Where each characteristic tends to come up:
- Wind load (EN 12210) — coastal sites, high-rise, anything with an engineering wind calculation behind it.
- Watertightness (EN 12208) — exposed facades, driven rain, monsoon and typhoon regions.
- Thermal transmittance (Uw) — central and northern Europe, and anywhere energy performance is part of the building permit.
- Sound insulation (Rw) — city centres, airports, rail corridors.
- Burglary resistance (EN 1627) — Germany, the Netherlands, Austria, and ground-floor residential in general.
- Fire — fire doorsets, tested to the EN 1634 series and classified under EN 13501-2, with the notified body involved continuously under AVCP system 1.
4. A note on the UK
Since Brexit, the UK has continued to recognise CE marking for most construction products, with UKCA as the alternative route. The position has been revised more than once, so confirm the current rules — and your project specification — before you assume either mark is accepted.
5. Where this sits in a sourcing order
The sequence matters, because everything downstream depends on it:
- Get the DoP first. Before anything else — before drawings are passed, before a single window is discussed. If there is no DoP, there is no declared performance, and every number that follows is a claim rather than a tested value.
- Check the manufacturer named on the DoP against the factory that is quoting you. This one step catches the most common substitution in the market.
- Check the classes against your site, not against the catalogue. A drawing review is where a class that is too low gets caught — on paper, before production.
- Check the notified body number is real and within the scope it claims.
- Keep the ITT report with the order file. It is the document your own client will ask you for later.
That is the part we run on every order: the drawing review sets the classes, the DoP and the test reports back them up, and the production checks confirm that what was declared is what gets built.
Checklist before you accept a CE claim
- DoP provided, manufacturer's name visible
- Notified body's four-digit number present and verifiable
- Classes declared, not just "CE marked"
- Classes match your site conditions and your specification
- ITT report on file with the order
- Fire doorsets: system 1, with the notified body's certificate — not a declaration
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