Find out how much energy your home is wasting and where the biggest savings are hiding.
The average UK home wastes a significant portion of its energy bill every year — through poor insulation, inefficient heating systems, and simple behavioural habits. Understanding where the losses are is the first step to reducing them.
According to the Energy Saving Trust, the typical UK home could save £300–£600 per year with a combination of insulation improvements, boiler upgrades, and smart energy habits — without sacrificing comfort.
| Source of waste | Typical annual cost | Fix & estimated saving |
|---|---|---|
| Poor or no loft insulation | £150–£250/yr | Top up loft insulation: save £100–£200/yr |
| Old inefficient boiler | £300–£500/yr extra | A-rated replacement: save £200–£400/yr |
| Unfilled cavity walls | £100–£200/yr | Cavity wall insulation: save £80–£160/yr |
| Draughts and air leakage | £60–£120/yr | Draught proofing: save £50–£100/yr |
| Single glazing | £80–£150/yr extra | Double glazing: save £60–£130/yr |
| Standby devices | £35–£75/yr | Smart plugs / habits: save £30–£70/yr |
| No smart thermostat | £80–£150/yr extra | Smart thermostat: save £75–£130/yr |
The Energy Performance Certificate (EPC) rates homes from A (most efficient) to G (least efficient). In 2025, the average UK home sits at band D. Government targets are pushing for all privately rented homes to reach a minimum of C by 2028, and owner-occupied homes to follow.
An EPC rating isn't just a letter — it translates directly to your energy bill. A D-rated home typically costs 20–30% more to run than an equivalent C-rated property. Moving from G to C can cut bills by 50% or more.
Not all energy improvements require large investment. Some of the most effective changes cost very little:
Air source heat pumps (ASHPs) are increasingly popular as a replacement for gas boilers, particularly with the government's Boiler Upgrade Scheme offering £7,500 grants. They can reduce carbon emissions significantly, but their financial payback depends heavily on your electricity tariff, insulation levels, and how much you currently pay for gas.
In a well-insulated home, an ASHP can reduce heating costs by 20–40% compared to an inefficient gas boiler. In a poorly insulated home, the benefits are much less clear until the fabric is improved first.
For the typical UK household (medium consumption), the Energy Price Cap for 2025 means an average bill of approximately £1,738 per year (Q1 2025 rate), rising or falling each quarter as Ofgem adjusts the cap. Actual bills vary significantly by household size, property type, and usage habits — ranging from under £800 for a small flat to over £3,000 for a large detached home.
The savings depend heavily on your current insulation levels. Adding loft insulation to a home with none can save £150–£250 per year. Upgrading from 100mm to 270mm (the recommended depth) saves around £30–£50/year. Cavity wall insulation saves £100–£200/year on average. For a solid-walled property (internal or external wall insulation), savings of £250–£400/year are possible but installation costs are much higher (£8,000–£20,000+).
Possibly. The Great British Insulation Scheme (GBIS) and ECO4 (Energy Company Obligation) schemes provide free or heavily subsidised insulation and heating upgrades to eligible households — typically those on means-tested benefits or with a low EPC rating. Contact your energy supplier or visit the government's Simple Energy Advice website to check eligibility. The Boiler Upgrade Scheme offers £7,500 grants towards heat pump installation for anyone replacing a fossil fuel boiler.