Internal

Heat loss

The heat loss card with sample data, rendered outside the auth wall so the caveat treatment can be reviewed.

Heat Loss

How quickly your home loses heat, calculated using the Home Energy Model — the methodology replacing SAP for official energy assessments.

Heat transfer coefficient

284

watts per degree

Heat loss parameter

3.14

per square metre

Peak heating need

6.5 kW

at -2°C outside

Where the heat goes

Through walls, roof, floor and windows70%
Through junctions and cold bridges11%
Through draughts and ventilation19%
ElementAreaU-valueHeat loss
External walls961.60154 W/K
Roof450.4018 W/K
Windows144.8067 W/K
Ground floor450.7032 W/K

Indicative only

Several key values were assumed from your property's age and type. Adding your EPC or more survey detail will sharpen this considerably.

2 things we had to assume — see the working for what and why.