Energy Efficiency

A dwelling’s energy efficiency rating is scored between 1 and 100 using the Standard Assessment Procedure (SAP). Energy Performance Certificates (EPC) display these ratings, and which broad ranking band they fall into, the highest attainable being an A rating (high energy efficiency, low running costs), and the lowest, G (low energy efficiency, high running costs).

Here, ratings and corresponding bands have been derived using the SAP 2012 (v9.93) methodology since this is the most recent version with three full years of data. Figure 3 shows the proportion of dwellings in local authorities which had the lowest rated properties (F or G) - the least energy efficient - and Figure 4 the highest rated properties (bands A, B or C).

Island and rural local authorities generally had the highest proportion of the least energy efficient dwellings. A total of ten local authorities had rates above the national average (3%), with the highest being Dumfries & Galloway (14%), Na h-Eileanan Siar (13%), Orkney Islands (12%) and Highland (9%). These local authorities also had lower proportions of properties in the highest efficiency bands than the national average.

In 2022-2024 four local authorities had statistically different, lower than the national average shares of F and G rated dwellings with Glasgow (<0.5%) being the lowest[1]. Correspondingly, seven local authorities also had higher than average proportions of A, B or C rated dwellings with North Lanarkshire (69%) being the highest compared to 55% for the national average. Island and rural local authorities tended to have lower than average proportions of A, B or C rated dwellings with Shetland Islands (16%), Orkney Islands (20%) and Na h-Eileanan Siar (22%) having the lowest.

It is important to bear in mind that the characteristics of the housing stock in an area can affect energy efficiency. For example, detached houses and housing which is off the gas grid are more likely to be F or G rated than other housing types while flats are more likely to be A, B or C rated.

Apart from Argyll and Bute, all 10 local authorities with higher proportions of F or G rated stock also had a higher than average proportion of houses and all 10 had a higher proportion of dwellings which were off the gas grid. Of the seven local authorities with higher than average proportions of A, B or C rated properties, all but South Lanarkshire had a lower than average proportion of dwellings off the gas grid.

The full local authority release also includes the share of properties rated EPC F or G using the SAP 2009 methodology. Dwellings with main heating fuels other than mains gas (for example oil or coal) have systematically lower SAP ratings in SAP 2012 v9.93 than in SAP 2009 and this is particularly true at the lower end of the SAP range. The main reason for this is that SAP fuel prices for these fuels have risen more than for mains gas between SAP iterations. As a result, average energy efficiency ratings tend to be slightly lower under SAP 2012 v9.93 compared to SAP 2009. A summary of the main differences between the two methodologies can be found in the 2019 SHCS Methodology Report.

On average across 2022-2024, 3% of dwellings had an F or G energy rating.

Figure 3: Percent Dwellings in Lowest Energy Efficiency Bands F or G (SAP 2012) by local authority, compared to Scotland average. SHCS, 2022-2024[2] [3]. [Note 1]

On average across 2022-2024, 55% of dwellings had a rating in energy bands A, B, and C.

Figure 4: Percent Dwellings in Highest Energy Efficiency Bands A, B or C (SAP 2012) by local authority, compared to Scotland average. SHCS 2022-2024. [Note 1]