Energy Performance of Buildings (Scotland) Regulations 2025: stock model research
Research to inform the thresholds of an A-G band scale for the forthcoming update to the Heat Retention Rating. We have a commitment to maintain equivalence between the SAP band C and a ‘Good’ Heat Retention Rating performance, i.e. an HRR band of C or better.
5 Baseline Results
Summarised in Table 1 and Tables 2A-C below are the baseline results of Scotland’s housing stock, based on the SHCS data assessed in our analysis. Using the Cotality RdSAP engine, we calculated SAP 9.94 and SAP 10 ratings for each of the properties in the dataset. A separate SAP rating was also included in the SHCS dataset (calculated using RdSAP 9.93).
As described in previous sections, some assumptions were made to create a workable RdSAP 9.94 and RdSAP 10.2 dataset from the v9.93 SHCS data. For this reason, we include both the original SHCS scores as well as the calculations from our engine, with the scores calculated by our engine giving a better indication of the variance between HEM and SAP when run against the same dataset.
| Band | SHCS RdSAP | Cotality RdSAP 9.94 | Cotality RdSAP 10 |
|---|---|---|---|
| A | 0.07% | 0.28% | 0.24% |
| B | 4.26% | 3.44% | 2.71% |
| C | 47.33% | 50.15% | 51.08% |
| D | 36.14% | 35.34% | 35.62% |
| E | 9.95% | 7.07% | 6.71% |
| F | 1.84% | 2.94% | 2.93% |
| G | 0.40% | 0.78% | 0.71% |
| SHCS RdSAP | Count | Percentage |
|---|---|---|
| Total | 2,525,121 | 100% |
| C or better | 1,304,471 | 51.66% |
| D or worse | 1,220,650 | 48.34% |
| Cotality RdSAP 9.94 | Count | Percentage |
|---|---|---|
| Total | 2,525,121 | 100% |
| C or better | 1,360,342 | 53.87% |
| D or worse | 1,164,779 | 46.13% |
| Cotality RdSAP 10 | Count | Percentage |
|---|---|---|
| Total | 2,525,121 | 100% |
| C or better | 1,364,310 | 54.03% |
| D or worse | 1,160,811 | 45.97% |
We have provided the full results in a spreadsheet that accompanies this report.
Contact
Email: EPCenquiries@gov.scot