Thermal Permeability in Windows and Doors
Standard: EN ISO 10077-1:2007
Standard Information
- Standard Number: EN ISO 10077-1:2007
- Title: Thermal performance of windows, doors and shutters - Calculation of thermal transmittance
- Part 1: General
- Status: Current
Thermal Transmittance Values
Key Parameters
- Uw: Overall thermal transmittance of window
- Ud: Overall thermal transmittance of door
- Ug: Thermal transmittance of glazing
- Uf: Thermal transmittance of frame
- Ψg: Linear thermal transmittance of glazing edge
Calculation Methods
The standard provides calculation methods for:
- Single and multiple glazed units
- Various frame materials
- Different panel configurations
- Thermal bridges
- Air cavity effects
Performance Classes
Typical thermal transmittance values (W/m²K):
- Basic: Uw/Ud ≤ 2.6
- Improved: Uw/Ud ≤ 1.8
- Enhanced: Uw/Ud ≤ 1.4
- High Performance: Uw/Ud ≤ 1.0
- Passive House: Uw/Ud ≤ 0.8
Influencing Factors
- Frame material and design
- Glazing type and configuration
- Spacer materials
- Panel construction
- Installation method
- Size and proportions
Application Guidelines
Recommended Values by Building Type
- Residential Buildings: 1.4-1.8 W/m²K
- Commercial Buildings: 1.6-2.2 W/m²K
- Low Energy Houses: 0.8-1.2 W/m²K
- Passive Houses: ≤ 0.8 W/m²K
Documentation Requirements
Required documentation includes:
- Calculation reports
- Component specifications
- Test certificates
- Installation instructions
- Maintenance guidelines
Verification Methods
- Calculation according to standards
- Hot box testing
- Computer simulations
- Field measurements
- Thermal imaging
Important Considerations:
- Consider local climate conditions
- Check national building regulations
- Verify energy efficiency requirements
- Ensure proper installation
- Account for thermal bridging