EPCs look mysterious because the points score is rarely explained on the certificate itself. Understanding what counts makes the upgrade conversation easier on both sides.
Heating system
A modern, efficient main heating source is the single biggest contributor. An older boiler quietly costs significant points across the rest of the certificate.
Insulation
Loft insulation, cavity-wall insulation and floor insulation each contribute. The assessor measures what they can see; uninsulated lofts are an obvious miss.
Glazing
Double-glazing in a high proportion of windows lifts the score; single-glazed windows pull it down disproportionately.
Lighting and hot water
A property with all-LED lighting and a well-insulated hot water cylinder picks up small, free points across the board.
Read the certificate alongside the points breakdown and the obvious wins almost identify themselves.
