Energy Performance of Buildings (Scotland) Regulations 2025: non-domestic buildings research
This research presents an illustrative comparison between the Energy Performance Certificate (EPC) ratings of five archetypal non-domestic buildings in Scotland when calculated using the current and revised rating systems.
Demonstration of Current and Revised Results
The key results of the modelling exercise are presented in the figure and tables which follow.
Table 2 lists the AR and corresponding energy band which were calculated for each of the five test cases using the current (v6.1.e) and revised (v6.2.a) EPC rating systems.
| Test case identifier | Current (v6.1.e) | Revised (v6.2.a) | ||
|---|---|---|---|---|
| AR | Band | AR | Band | |
| Aberdeen Office | 39 | C | 94 | D |
| Aberdeen Storage | 36 | C+ | 166 | G |
| Dundee School | 19 | B+ | 48 | B |
| Kyle Industrial | 282 | G | 436 | G |
| Wick Retail | 43 | C | 70 | C |
A graphical representation of the current and revised AR values calculated for each of the five test cases is illustrated in Figure 2.
In addition to the calculated BER and SER, Table 3 displays the following performance indicators which are also required to be reported on the building’s EPC:
- The rate of ‘direct emissions’, in kgCO2/m2, which are those emissions arising from the use of fuels other than grid-supplied electricity and district heat networks for regulated end uses in the Actual building. (This indicator is not reported on the EPC under the current rating system but is now required under the revised system.)
- The rate of energy use, in kWh/m², which is the total energy used for regulated end uses in the Actual building.
- The primary energy indicator, in kWhPE/m², which is the rate of total primary energy consumption for regulated end uses in the Actual building.
| Test case identifier | BER | Rate of direct emissions | Rate of energy use | Primary energy indicator | SER |
|---|---|---|---|---|---|
| kgCO2/m2 | kgCO2/m2 | kWh/m2 | kWhPE/m2 | kgCO2/m2 | |
| Aberdeen Office | 39 | 30.6 | 206.45 | 256.02 | 20.8 |
| Aberdeen Storage | 36.1 | 29.8 | 186.27 | 227.5 | 10.9 |
| Dundee School | 19.3 | 13 | 107.36 | 138.69 | 20.2 |
| Kyle Industrial | 282 | 266.7 | 941.85 | 1148.92 | 32.3 |
| Wick Retail | 42.6 | 0.7 | 296.38 | 451.8 | 30.4 |
It is worth noting that the BER values calculated for each of the five test cases are identical in v6.1.e and v6.2.a (since the method for estimating the energy use and emissions is unchanged in the software). The difference between the current and revised EPC rating systems lies in how the AR is derived from the BER and mapped onto a revised band scale.
Table 4 displays the ‘main heating fuel’ and the ‘building environment’ as identified by the software during the calculation. These are also reported on the building’s EPC.
- The main heating fuel is the fuel which delivers the greatest total thermal output for space or water heating in the Actual building
- The building environment is the servicing strategy which contributes the largest proportion of the building’s CO2 emissions.
| Test case identifier | Main heating fuel | Building environment |
|---|---|---|
| Aberdeen Office | Natural Gas | Heating and Natural Ventilation |
| Aberdeen Storage | Natural Gas | Heating and Natural Ventilation |
| Dundee School | Natural Gas | Heating and Mechanical Ventilation |
| Kyle Industrial | Oil | Heating and Natural Ventilation |
| Wick Retail | Grid Supplied Electricity | Heating and Natural Ventilation |
Contact
Email: EPCenquiries@gov.scot