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What inputs do I need for the energy efficiency calculation (SIA 380/1)?

Last updated August 7, 2026

Explanation

For the heating demand calculation per SIA 380/1, you need the following inputs:

- Weather station and altitude in the building details - Zones with usage classification and at least one EBF zone in zone management - Components with U-values (components without U-values block the calculation)

Recording thermal bridges is recommended: without them, vyzn calculates with a warning but the results are less accurate.

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