Calculator
Heat loss calculator
A quick estimate of your building's thermal demand in kW - no registration.
Enter basic building data: heated area, building type, insulation standard and climate zone. The calculator returns the estimated heat loss in kW with a split between transmission (walls, windows, roof) and ventilation. This is a preliminary estimate based on averaged coefficients. It does not replace a full heat load calculation.
Heat loss calculator
Four basic building inputs, result in seconds.
How it works
Enter 4 basic building inputs: heated area, building type, insulation standard and climate zone.
The calculator applies averaged W/m² coefficients for the age and insulation category, then corrects the result for climate zone and building type.
You get the estimated heat loss in kW with a ±10% uncertainty band, a benchmark for your category, and a 70/30 transmission / ventilation split.
For a full heat load calculation in accordance with EN 12831-1 (wall layers, windows, thermal bridges), use the HeatAlgo app. Full compliance covers residential buildings with natural, mechanical, or MVHR ventilation, without air transfer devices (ATDs).