Overview
EN ISO 12567-1:2010 - Thermal performance of windows and doors - Determination of thermal transmittance by the hot-box method - Part 1: Complete windows and doors (ISO 12567-1:2010) - specifies a laboratory method to measure the thermal transmittance (U-value) of complete window and door systems using the hot-box method. The standard covers the whole assembly including frames, sashes, shutters, blinds, screens, panels, door leaves and fittings, and produces aggregate thermal-transmittance results representative of the product in service.
The document is the ISO international text adopted by CEN/SIST and supersedes earlier editions. It is intended to support standardized comparisons and product-specific tests under steady-state conditions.
Key topics and technical requirements
- Scope and exclusions: applicable to complete windows and doors; not applicable to edge effects outside the specimen perimeter, solar radiation effects, air leakage through the specimen, or roof/projecting windows where the external face projects beyond the cold-side roof surface (see ISO 12567-2 for roof windows).
- Measurement principle: hot-box (calibrated and guarded) technique derived from ISO 8990 to determine steady-state heat flow and compute U-values.
- Specimen and apparatus requirements: specifications for test specimens, surround panels, calibration panels and metering chambers; instrumentation for temperature, heat flow and air movement.
- Data and calculations: symbols and definitions for thermal quantities, calibration procedures, methods for expressing standardized results, and annexes with environmental temperature calculations.
- Quality and uncertainty: calibration transfer procedures, examples of calibration tests, and uncertainty analysis (informative annexes provide guidance on heat balance and uncertainty evaluation).
Practical applications and users
This standard is used to:
- Provide certified U-values for product data sheets and regulatory compliance.
- Support product development and performance benchmarking for window and door manufacturers.
- Supply test methods for accredited laboratories performing thermal performance testing.
- Inform building designers, energy modelers and specifiers who need validated thermal transmittance data for energy calculations, compliance and retrofit decisions.
- Aid regulators and certification bodies in verifying declared thermal performance.
Typical users: test laboratories, manufacturers, architects, facade engineers, building physicists, certification bodies and national standards organizations.
Related standards
Relevant referenced documents include: ISO 7345, ISO 8990, ISO 8301, ISO 8302, ISO 9288, ISO 10211, EN 12898, and IEC 60584-1. For projecting and roof windows, see ISO 12567-2.
Keywords: ISO 12567-1:2010, hot-box method, thermal transmittance, U-value, thermal performance, windows and doors, SIST, calibrated hot box.