Guides & Resources
Learn everything about U-value calculations, UK building regulations, and thermal performance.
Fundamentals
How to Calculate U-Values
A complete guide to calculating thermal transmittance (U-values) for walls, roofs, and floors following BS EN ISO 6946 methodology.
Standards
Understanding BR 443
Learn about BR 443 conventions for U-value calculations, including design thermal conductivity values and surface resistances.
Regulations
Part L 2021 Compliance
Everything you need to know about meeting Part L 2021 requirements for new builds, extensions, and renovations.
Advanced
Thermal Bridging Guide
How to account for thermal bridging from studs, fixings, and other repeating elements in your calculations.
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