Introduction

This chapter discusses findings on energy efficiency ratings and heating systems and how this differs by tenure. It then goes on to discuss insulation measures in dwellings, smart meters by tenure and subjective overheating, then finishes with the average cost of improving dwellings to an energy efficiency rating band C.

For an introduction and summary of main findings in this report as a whole, please see the Introduction and key findings page.

Energy efficiency rating

Overall, the energy efficiency of the English housing stock has continued to improve. In 2023, the average SAP rating of English dwellings was 67 points, up from 45 points in 1996. This longer-term upward trend was evident in all tenures and largely driven by improvements in the prevalence of the most common energy efficiency measures across the stock, particularly cavity wall insulation, boiler upgrades from standard to condensing combi and full double glazing, Annex Table 2.1 and Figure 2.1.

Over the last 10 years, the biggest improvements were in owner occupied and private rented dwellings, an 8 point increase for both. However, the social rented sector continued to be the most energy efficient sector, where the average SAP rating of local authority dwellings increased from 65 in 2013 to 70 in 2023, and similarly, the average SAP rating of housing association dwellings increased from 66 in 2012 to 71 in 2023. This is not surprising given the age and type of dwellings in the private sector. The social sector contains a higher proportion of purpose built flats compared to the private sector, which have less exposed surface area (external walls and roofs) through which heat can be lost.

When compared to 2019 (pre-COVID), energy efficiency increased 3 points for owner occupied dwellings (from 64) and 2 points for both private and social rented sector homes (from 64 and 69 respectively), Annex Table 2.1, Figure 2.1.

Figure 2.1: Mean SAP rating, by tenure, 1996 to 2023

^{Base: 1996-2019 all dwellings; 2020-2021 occupied dwellings; 2022 modelled and observed data; 2023 all dwellings
Notes:
1) from 2018 the SAP 2012 methodology used new U values for cavity, solid and stone walls, both insulated and uninsulated.
2) underlying data are presented in Annex Table 2.1
Sources:
1996-2007: English House Condition Survey, dwelling sample
2008-2019: English Housing Survey, dwelling sample
2020-2021: English Housing Survey, modelled data based on occupied dwellings
2022: English Housing Survey, dwelling sample, modelled and observed data based on all dwellings
2023: English Housing Survey, dwelling sample}

The proportion of dwellings in the highest SAP energy efficiency rating (EER) bands A to C increased over the last decade, from 23% in 2013 to over half of all dwellings (52%) in 2023, Annex Table 2.3. 

Figure 2.2 demonstrates the transition of the individual EER bands from 2013 to 2023, highlighting the overall improvement in the energy efficiency of the English housing stock.

Figure 2.2: Energy efficiency rating bands, 2013 to 2023

^{Base: 2013-2019 all dwellings; 2020-2021 occupied dwellings; 2022 modelled and observed data; 2023 all dwellings
Notes:
1) from 2018 the SAP 2012 methodology used new U values for cavity, solid and stone walls, both insulated and uninsulated.
2) EER bands A and B are grouped. There are currently insufficient numbers of Band A properties existing for which meaningful estimates can be made through a sample survey.
3) due to the COVID-19 pandemic, EHS surveyors did not conduct any inspection of vacant properties in 2020. Although an external inspection of vacant homes occurred in 2021, the 2021 combined survey dwelling sample is for occupied properties only.
4) underlying data are presented in Annex Table 2.3
Sources:
2013-2019: English Housing Survey, dwelling sample
2020-2021: English Housing Survey, modelled data based on occupied dwellings
2022: English Housing Survey, dwelling sample, modelled and observed data based on all dwellings
2023: English Housing Survey, dwelling sample}

Energy efficiency rating band, by tenure

In 2023, the most common EER band for owner occupiers and private rented dwellings was band C (both 45%). Although social rented dwellings had a higher proportion, with 67% for local authority dwellings and 68% for housing association dwellings, this is the first time that the most common EER band in the private rented sector was band C, Figure 2.3. 

Figure 2.3: Energy efficiency rating bands, by tenure, 2023

^{Base: all dwellings
Notes:
1) underlying data are presented in Annex Table 2.2
Source: English Housing Survey, dwelling sample}

Energy efficiency rating band, by dwelling characteristics

In 2023, the most energy efficient homes (EER bands A to C) were more likely to be newer dwellings. The majority of dwellings built after 1990 were in bands A to C (86%), whereas just 23% of dwellings built prior to 1919 had an EER of A to C, Annex Table 2.4.

Purpose built high rise (82%) and purpose built low rise (72%) flats had the highest proportion of A to C rated dwellings compared with all other dwelling types (between 39% to 52%), while bungalows (61%) had the largest proportion of D to G rated dwellings compared to all other dwelling types (between 18% to 54%).

Energy efficiency rating band, by region

Overall, the North East and London had a higher proportion of energy efficient dwellings compared to other regions. In the North East 65% of dwellings had an EER of A to C compared with 59% in London and 45% to 55% in all other regions, Figure 2.4 and Annex Table 2.4.

Figure 2.4: Dwellings with energy efficiency rating A to C, by region, 2023

^{Base: all dwellings
Notes:
1) underlying data are presented in Annex Table 2.4
Source:
2023 English Housing Survey, dwelling sample}

Heating system

There are two key methods of increasing the energy efficiency of existing dwellings: upgrading the dwelling’s heating system and increasing insulation.  

Between 1996 and 2023, the proportion of homes with central heating increased (from 80% to 93%), while the proportion of homes with room heaters as their main heating source – the least cost-effective and most inefficient method of heating – decreased from 12% to 3%, Annex Table 2.5.

In 2023, owner occupied and local authority homes had the highest proportion of homes with central heating (both 95%), followed by housing association homes (91%), and private rented homes (86%) with the lowest. In addition, the proportion of dwellings in the private rented sector with fixed room heaters were higher than in other tenures (8% compared to 2% for owner occupied and 1% for the social rented sector), Annex Table 2.6.  

Condensing boilers are generally the most efficient boiler type and since the mid-2000s have been mandatory for new and replacement boilers. As expected, the proportion of dwellings with condensing or condensing-combination boilers has increased considerably since 2001. In 2001, just 10% of homes had combination boilers and 28% had condensing-combination boilers. By 2023, this increased to 19% and 55% respectively, Figure 2.5 and Annex Table 2.7.

Figure 2.5: Boiler types, 1996 to 2023

^{Base: 1996-2019 all dwellings; 2020-2021 occupied dwellings; 2022 modelled and observed data; 2023 all dwellings
Notes:
1) Condensing and condensing-combination boilers were rare in 1996, so data on these types were not collected. Values of zero have been assumed to reflect this.
2) Underlying data are presented in Annex Table 2.7
Sources:
1996-2007: English House Condition Survey, dwelling sample
2008-2019: English Housing Survey, dwelling sample
2020-2021: English Housing Survey, modelled data based on occupied dwellings
2022: English Housing Survey, dwelling sample, modelled and observed data based on all dwellings
2023: English Housing Survey, dwelling sample}

Private rented and housing association homes were also the most likely to have no boiler in their property at all (19% and 18% respectively), compared to 13% of local authority dwellings and 7% of owner occupied.

Overall, homes in the social rented sector were more likely to have newer, more energy efficient condensing-combination boilers (67%) compared to private rented and owner occupied dwellings (61% and 60% respectively). This may reflect the age and type of dwellings across tenures, Annex Table 2.8.

Insulation

The second main method of increasing a dwelling’s energy performance is by installing or upgrading insulation. Standard insulation measures include installing cavity or solid wall insulation, loft insulation and double glazing. Installation of these measures has increased in the last 10 years, though the changes are not as substantial as for other improvements.

In 2023, insulation with a thickness of 200mm or more had been installed in 40% of dwellings which had a loft (up from 37% in 2013). Just over half (53%) of dwellings had cavity or solid wall insulation (up from 46% in 2013) and 89% of homes in England had full double glazing, up from 80% of homes in 2013, Figure 2.6 and Annex Table 2.9.

Figure 2.6: Insulation measures, 2013 to 2023

^{Base: 2013 to 2019 all dwellings; 2020-2021 occupied dwellings; 2022 modelled and observed data; 2023 all dwellings
Notes:
1) Percentages are based on all dwellings, including those with no loft or other wall type.
2) Underlying data are presented in Annex Table 2.9. See footnotes in this table for further detail on methodology for cavity and solid wall insulation.
Sources:
2013-2019: English Housing Survey, dwelling sample
2020-2021: English Housing Survey, dwelling sample
2022: English Housing Survey, dwelling sample, modelled and observed data based on all dwellings
2023: English Housing Survey, dwelling sample}

Among dwellings with solid walls, the social rented sector had a higher proportion of dwellings with solid wall insulation (local authority housing 39%, and housing association 28%) compared to both private rented (10%) and owner occupied dwellings (9%), Annex Table 2.10.

Private rented dwellings had the lowest proportion of cavity wall insulation (60%) compared to all other tenures (73% owner occupied, 78% local authority and 80% housing association dwellings), Figure 2.7.

Figure 2.7: Wall insulation, by main wall type and tenure, 2023

^{Base: dwellings with predominantly cavity walls (green); dwellings with predominantly solid walls (blue)
Note: underlying data are presented in Annex Table 2.10
Source:
Source: English Housing Survey, dwelling sample}

Smart meters and electricity payment methods

The replacement of traditional meters with smart meters is a national infrastructure upgrade that aims to make the country’s energy system cheaper, cleaner and more reliable. Smart meters offer a range of intelligent functions. For example, they can tell residents how much energy they are using in pounds and pence via an In-Home Display. This information should help customers manage their energy use, save money and reduce emissions. When smart meters are working properly, they communicate automatically with energy suppliers, which avoids manual meter reads and provides customers with accurate bills.

The English Housing Survey asks residents whether they have a smart meter. This section of the report is based on the information given by the resident and focuses on electricity meters only.

In 2023-24, over half of households in England reported having an electricity smart meter (55% or 14 million households), this represents an increase compared with 2022-23 (53%), Annex Table 2.11 and Figure 2.8.

In 2023-24, owner occupiers and social renters were more likely to report having an electricity smart meter (59% and 53% respectively) compared to private renters (47%), Figure 2.10. Since 2022-23, the proportions of households with a smart meter increased for both owner occupiers (59% in 23-24 vs 56% in 22-23) and private renters (47% in 23-24 vs 43% in 22-23).

Figure 2.8: Electricity smart meters, 2023-24

^{Base: all households
Notes:
1) Self reported presence of electricity smart meters
2) Underlying data are presented in Annex Table 2.11
Source: English Housing Survey, full household sample}

Households who paid for their electricity by direct debit (57%) or pre-payment token (54%) were more likely to report having an electricity smart meter than those who paid on receipt of the bill (49%), standing order (47%) or by other methods (33%) e.g. included in the rent, fixed annual bill, Annex Table 2.11.

The EHS results are broadly in line with smart meter statistics from the Department for Energy Security and Net Zero (DESNZ). As of 30 September 2024, 68% of domestic properties had an electric smart meter. Differences between EHS and DESNZ statistics are likely to reflect the different time periods for data collection and the EHS survey reliance on self-reporting.

Subjective overheating

The English Housing Survey includes a subjective measure for gauging whether residents feel any part of their home gets uncomfortably hot and, if so, which parts.

In 2023, 12% of households reported at least one part of their home got uncomfortably hot. This was an increase from 11% in 2022.

Those in the owner occupied sector, (13%) were more likely to report at least part of their home got uncomfortably hot than those in the private and social rented sectors (both 11%).

Households living in detached houses (16%) were most likely to report overheating in their homes, compared with 6% in high rise flats, 11% in low-rise flats and a range of 9 to 12% for terraced and other types of houses, Annex Table 2.12.

Households in newer homes were more likely to report overheating than those in older homes. Older homes can be more difficult and costly to insulate compared to new homes.  In 2023, 14% of residents in homes built from 2003 onwards reported at least one part of their home got uncomfortably hot. This was a higher proportion than for those in homes built between 1919 and 1964 (ranging from 10% and 11%).

Costs to improve to an energy efficiency rating band C

This chapter looks at the cost of improving dwellings with an energy efficiency rating (EER) band of D or lower to an EER band of at least C, by dwelling characteristics.

In 2023-24 almost half of the dwellings in England (46%) would be eligible to be improved to an EER band C or higher, around 2% (440,000) would either not eligible or d be unable to reach band C, and the remaining dwellings in the stock already had an EER band of C or higher, Annex Table 2.13.   

The mean cost to improve dwellings to an EER band C was £7,320 per dwelling. The median cost per dwelling was slightly higher, at £8,017 to improve dwellings to band C, Annex Table 2.14.

Private sector (both owner occupied and private rented) dwellings had a higher average cost than social sector dwellings; £7,515 compared with £5,489. Within these sectors, owner occupied and private rented dwellings would cost on average £7,714 and £6,864, respectively to improve to a band C, compared to £5,086 and £5,752 required to improve local authority and housing association dwellings, Annex Table 2.14, Figure 2.9.

Figure 2.9: Average cost to improve to energy efficiency rating band C, by tenure, 2023

^{Base: all dwellings able to be improved to an EER band C
Notes: Underlying data are presented in Annex Table 2.14
Source: English Housing Survey, dwelling sample}

The age and type of dwelling have a large influence on the energy efficiency of homes, and it is not surprising that the cost to bring older dwellings up to a band C was higher. Dwellings built before 1919, which are more likely to be of solid wall construction, had the highest average cost to improve to a band C, at £10,788, followed by dwellings built between 1919 to 1944 (£6,849).

Detached dwellings had the highest average cost to reach band C, at £8,570, closely followed by medium/large terraced houses (£8,547). Conversely, purpose built, low rise and purpose-built, high rise flats had the lowest average costs, at £4,023 and £2,741, respectively.

As expected, dwellings with an EER rating of F and G had a higher average cost to improve to a band C than D or E rated dwellings; £16,983 compared with £6,018 and £12,381 respectively.

The North East had the lowest average cost of £5,698 to achieve an EER rating of band C, followed by Yorkshire and the Humber (£6,335), compared with all other regions (£7,142 to £8,282), Figure 2.10.

Figure 2.10: Average cost to improve to energy efficiency rating band C, by region, 2023

^{Base: all dwellings able to be improved to an EER band C
Notes: Underlying data are presented in Annex Table 2.14
Source: English Housing Survey, dwelling sample}

Banded costs to improve to an energy efficiency rating band C

It would cost between £1,000 to £4,999 to improve just over a quarter (28%) of eligible dwellings to an EER band C and around £5,000 to £9,999 to improve just under half (43%). Around 5% of eligible dwellings would require less than a £1,000 investment, whereas 16% of eligible dwellings would require larger investments of between £10,000 and £14,999. The remaining 8% would need more than £15,000 to improve to a band C, Figure 2.11, Annex Table 2.15.

Figure 2.11: Banded cost to improve to energy efficiency rating band C

^{Base: all dwellings able to be improved to an EER band C
Notes: Underlying data are presented in Annex Table 2.15
Source: English Housing Survey, dwelling sample}

Owner occupied dwellings (9%) were more likely to cost £15,000 or more to bring up to band C compared to private rented (6%), housing association (2%) and local authority (1%) dwellings,  Annex Table 2.15.

London (63%) was more likely to have dwellings that cost between £5,000 and £9,999 to improve to band C than other regions (33% to 48%).