EN 12428 - Industrial, commercial and garage doors - Thermal transmittance - Requirements for the calculation
EN 12428 specifies the method for determining the thermal transmittance (U) of industrial, commercial and garage doors and gates, with the aim of assessing their thermal insulation performance.
Aim
- Provide a unified calculation procedure to declare thermal transmittance (U in W/m²-K);
- Allow manufacturers to declare performance in the Declaration of Performance (DoP) in accordance with the harmonised standard EN 13241.
Scope of Application
- Non-transparent or partially transparent doors and gates;
- Includes manual or motorised doors with insulating elements (sandwich panels, insulation, etc.);
- Excludes exclusively glazed or automatic pedestrian doors (other specific standards).
Main contents
U-value calculation:
- based on the geometric and thermal characteristics of the building material;
- takes into account thermal bridges, joints and frames.
Possibility of using:
- Values measured in laboratory (ISO 12567-1),
- simplified formulae provided in the standard for typical cases.
Relevance of:
- total surface area,
- type of structure (monolithic or sectional),
- accessory elements (portholes, rails, seals, etc.).
In practice
It is not mandatory for all installations, but often required in:
- buildings with energy criteria or environmental certifications (e.g. NZEB, LEED, etc.),
- public specifications and local regulations (depending on the country);
- It helps to demonstrate compliance with European energy directives (e.g. EPBD - Energy Performance of Buildings Directive).