What Heat Loss does
A room, zone and building heat-loss breakdown with a reproducible calculation trace.
How it fits into the workflow
- Define each zone and its exposed dimensions.
- Add openings, U-values, ventilation and thermal-bridge allowances.
- Review fabric and ventilation losses separately before any equipment-sizing work.
Where it can save time
Once zones and envelope elements are recorded, the tool separates fabric and ventilation losses and makes option changes easy to compare. That is quicker than rebuilding a whole worksheet every time an area, U-value or air-change assumption changes.
Compliance and professional limits
The estimate can inform early energy discussions and Approved Document L coordination, but it is not a validated EN 12831 or ACCA Manual J calculation and must not be used to size final heating equipment.
Professional boundary: This is a concept-stage estimate, not a validated EN 12831 or Manual J calculation and must not size final heating equipment.
In summary
Heat Loss is most useful when its saved output remains connected to the project decision and is reviewed within the limits described above.