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Heat Loss
UK room heat loss from U-value fabric conduction plus ventilation infiltration, for space-heating estimates.
The Ensign ToolboxHeat LossUK room heat loss from U-value fabric conduction plus ventilation infiltration, for space-heating estimates.
Room
Used to label this room in the multi-room breakdown & CSV
Temperatures
°C
°C
K
Room Dimensions
m
m
m
Envelope
Reduces ΔT for non-external boundaries
m²
m²
U-values (W/m²·K)
Ventilation & Gains
%
Realistic MVHR: 70–90 %
W
Reported separately — not subtracted from design heat loss (per CIBSE design-day method)
Enter room dimensions to calculate heat loss