Calculating the target primary energy rate and target emission rate

In compliance with the approved document section 1 & 2 (regulations 24, 25, 25B, 26, 26C, 27 & 27C) the BER / TER & BPER / TPER values are obtained from the simulated carbon dioxide emissions and energy use of two buildings.

The ‘actual building’, which forms the basis of the BER & BPER calculations, is the building as designed, but subject to standard operating conditions dictating levels and patterns of occupancy, internal gain and minimum ventilation.

The ‘notional building’, which forms the basis of the TER & TPER calculations, is a version of the actual building modified in accordance with rules relating to glazing area, insulation, system efficiency and other factors. The notional building is also subject to the standard operating conditions. The notional building is created within the BRE SBEM tool.

Both buildings have monthly heat balances performed for standard weather data appropriate to the building location. Results are automatically fed into the BRUKL compliance calculator provided by BRE.

The standard operating conditions are functions of the building type and the activities occurring within each room. They are laid down in the National Calculation Methodology (NCM) Modelling Guide^[3].