Why have my heat losses changed since the last time I opened the project?

We occasionally have to make small updates to how heat losses are calculated, for example to fix minor bugs.

Autumn 2026: we are updating the default temperatures of heated and unheated spaces in line with new guidance. These updates will automatically be applied to heat loss calculations on new projects. On pre-existing projects, you will have the option to accept the new heat loss calculations, or to view the existing project as it was without making any further changes to the floor plan.