Did you know that more than 56% of homes in England are currently classed as having below-average energy efficiency? For many households, this means skyrocketing energy bills, drafty winters, and an outsized carbon footprint.
Home improvement specialists Eurocell analysed national EPC data to map out England’s least efficient homes—and the results reveal stark contrasts between regions, shining a spotlight on areas most in need of urgent upgrades.
What is an EPC?
EPC stands for Energy Performance Certificate and is a document that outlines a home's energy efficiency. Homes are rated on a scale from A (most energy efficient) to G (least energy efficient), and a potential energy rating highlights the maximum potential efficiency of a property if all possible recommendations are followed and implemented.
An EPC is required whenever you sell a property, rent a property out, or build a new property. EPCs are valid for 10 years and cover that property no matter how many times it's sold or rented out during that time.
The national picture
Across England, more than 56% of homes are classed as having below-average energy efficiency, scoring a D or lower.
The D rank makes up the largest national share, with over 9.3 million homes in this tier. By contrast, only 74,770 homes have scored top marks and have gained an A certification - just 0.3% of the country's available housing stock.
Where are England’s least-efficient homes?
According to the research, Eden in Cumbria has the least energy-efficient housing in England. 4,319 (17%) of the 24,361 homes here are classed as either an F or G on the rating scale.
Nestled in the scenic Lake District, Eden is famed for its natural beauty but struggles with an ageing housing stock. Many homes here are traditional stone cottages, often built before insulation standards existed. While picturesque, these properties are notoriously inefficient at retaining heat, leaving residents with steep energy bills and cold winters.
West Devon comes next in the rankings, with over 15% of its 26,169 homes gaining an F or G EPC rating. Home to vast swathes of Dartmoor National Park, much of the population in West Devon is spread across rural villages, without access to energy provided by the national grid. Many homes here rely on costly heating systems like oil or solid fuel, dragging down the average rating.
Cornwall also has some of the least energy-efficient homes in the country, with 14% of properties falling into the bottom two bands. The coastal county is home to a significant number of older, solid-wall properties that struggle to meet modern insulation standards. Coastal properties also suffer from a much damper climate than some other parts of the UK, meaning that there can be serious damp and mould issues.
Common problems that lead to inefficiency
Many of the areas identified as having inefficient housing have common traits that can help explain their EPC scores:
- Older housing stock: Many of the homes in areas such as Eden, Shropshire, East Lindsey and Norfolk are upwards of 100 years old. When they were built, energy efficiency wasn’t as much of a consideration, and retrofitting older solid-wall properties with measures such as cavity wall insulation can be impossible.
- Rural isolation: Homes in rural areas can often be cut off from the energy network, so rely heavily on oil or solid-state fuel sources, which are expensive and are generally considered to be more polluting than mains gas. Their location can also make it difficult for contractors to retrofit new systems, such as heat pumps.
- Economic challenges: Many regions, especially rural areas, have lower household incomes, meaning saving up for costly upgrades can be difficult.
Where are England’s most efficient homes?
Tower Hamlets has proportionally the most energy-efficient housing in the country, according to Eurocell’s research. This bustling borough in East London has seen a large wave of new housing developments in the last few years, all built to modern efficiency standards. High-rise buildings here come equipped with advanced insulation and triple-glazed windows, which contribute to an impressive 34.39% of homes having above-average EPC ratings.
Vale of White Horse in Oxfordshire ranks second for having some of the most energy-efficient homes in England. While much of the area is rural, commuters to Oxford, Swindon and London have created a demand for new high-end homes, all of which come with top energy efficiency scores. Many new properties here come with solar panels, air source heat pumps, triple-glazed windows and more. This demand has led to 26.66% of homes in the area scoring top EPC ratings.
Greenwich also ranks highly in the research, with 23.63% of properties scoring either an A or B on its EPC certificate. Buyers here can expect to pay a premium, whoever, as Rightmove suggests that the average sale price this year is £613,053.
How to improve your EPC rating
When you get your EPC, you’ll also be given a potential rating, showing what your property could be if you upgrade certain features. Improving the energy efficiency of your home or rental property not only helps lower energy bills but also boosts the property’s value and reduces environmental impact.
Upgrade of energy-efficient PVC-U windows
The vast majority of homes are now equipped with doubled-glazed window frames, however, the technology behind them has evolved substantially in the past 20 years. Upgrading to modern PVC-U windows can help reduce heat loss by up to 18% and save you hundreds of pounds on your energy bills.
Seal any gaps to block any draughts
Draughts and air leaks around windows and doors can significantly impact energy efficiency. Left unchecked, what starts as a small draught can spiral into a much larger structural issue.
Use a high-quality sealant to seal up any problem areas, and you should notice a warmer home straight away.
Invest in energy-efficient doors
Alongside windows, the front and back doors are another major source of heat loss. Swapping them out for composite doors that provide a better seal can boost your energy savings, as well as provide a more secure entrance to your home.
Add to or upgrade your insulation
Many older properties suffer from either too little or no loft and cavity wall insulation. Up to 33% of a home’s heat can be lost through its roof. Homes are required to have a minimum of 270mm of loft insulation, but many older properties do not. To help with the cost of upgrading insulation, the government’s Great British Insulation Scheme can provide cheaper or even free loft and cavity wall insulation, assuming you meet the necessary requirements.
Consider renewable energy sources
If budget allows, installing solar panels, an air source heat pump or a more efficient boiler can give your property a significant energy boost, as well as lower your energy bills. Modern, energy-efficient LED lights can also help bring down your energy costs.
How to find your EPC rating
If you’re curious about what your property’s EPC rating is, you can find it at www.gov.uk/find-energy-certificate. This link contains information about your current and potential rating, as well as recommendations on how to improve your rating, and how much money you could save on your energy bills by doing so.
Methodology
Eurocell analysed data from the Department of Levelling Up, Housing and Communities which contains figures for every household in England and Wales. The number of ratings was contrasted with the number of properties to determine which areas have the best/worst homes in terms of energy efficiency.
Data correct as of December 2024.