: What it means
A Building Energy Rating (BER) certificate indicates your building's energy performance. It is similar to the energy label for household appliances.
The certificate rates your building on a scale of A-G. A-rated homes are the most energy efficient and will tend to have the lowest energy bills. G-rated are the least energy efficient.
All newly built homes are required to have a minimum A3 rating while a typical rating for existing homes depends largely on the age of construction and building type. Table 2 Right shows the percentages of BER Ratings associated with dwelling age.
(CSO statistical release, 21 April 2017)
There are two measurements which determines which rating your building is given: the energy value and a CO2 Emissions Indicator. The Energy value is measured in KWh/m2/yr which relates to KiloWatt hours per m2 per year. That is essentially the amount of energy used in the building every year to supply the needs of the household. The C02 Emissions Indicator is an estimate of the carbon footprint of the building.