A Building Energy Rating (BER) certificate is an energy label for your home — like
the labels on household appliances. It rates energy performance and carbon emissions on a scale from
A1 (most efficient) to G (least efficient).
A1 Super energy efficient — warm, comfortable, running on minimal energy (max 25 kWh/m²/yr).
G Least efficient — often cold and damp with huge energy demand and high bills.
Choosing an A-rated extension means lower energy bills and a higher standard of living — modern,
well-insulated, and warm year-round on minimal heating.