How to improve an EPC rating from C to B
Going from C to B means reaching a score of 81 from between 69 and 80. B is close to new-build territory, so the cheap measures are often used up by this point. Solar panels are the usual next step, and your EPC's recommendations show whether B is possible. No rule requires homes to reach B.
Decide whether B is worth chasing
C is the level the government plans to use for private rented homes by 2030. No law asks homeowners or landlords to reach B. So this is a choice, and it is worth being clear about why you want it: lower bills, comfort, a green mortgage offer or simply a better rating.
It helps to know what B represents. The Office for National Statistics reported a median score of 84 for homes built after 2012. In other words, a typical recent new-build sits in band B. An older home reaching 81 is matching modern construction with a building that was not designed for it.
Check whether your EPC shows a route
Look up your certificate and compare the current and potential scores. A home on 79 needs 2 points. A home on 69 needs 12.
If the potential rating is B, the recommendations show one way there. If it stays at C, the assessor's list does not reach it, and getting there will mean work beyond the list or a change of heating or generation. Ask an assessor to model the options before you pay for anything large.
Measures that usually matter from C
Most C-rated homes already have a modern boiler and some insulation, so the options look different from lower bands.
| Measure | Typical cost | What to know |
|---|---|---|
| Solar panels, about 4.5 kWp | About £7,600 | Often the main route, because it does not need the building opened up |
| Floor insulation, suspended floor | About £1,400 to £2,500 | Best done when floors are already up |
| Solid wall insulation | About £12,000 to £15,000 | Only where walls remain uninsulated |
| Air source heat pump | About £12,000 before any grant | The effect on today's rating varies |
These are the Energy Saving Trust's typical figures, mostly for a semi-detached home in Great Britain. Costs vary with the home, the region and the installer, so treat them as a starting point and get quotes.
Check the remaining gaps too. A loft top-up, a better cylinder or heating controls are small jobs that may still be available and are worth finishing first.
A typical order of work
- Finish any small items on your recommendations list.
- Time disruptive work with other projects. Floor insulation fits a new floor, and wall insulation fits a re-render or a full redecoration.
- Add solar panels if the roof suits them. Check orientation, shading and whether planning limits apply.
- Look at a heat pump when your boiler is nearing the end of its life, not while it has years left.
- Commission a new EPC at the end, because the rating only changes when one is lodged.
What is unrealistic from C
- Reaching B through lighting, draught-proofing or better controls alone, unless you are within a point or two.
- Paying back the cost quickly. Solid wall insulation saves about £280 a year in a semi-detached home, which is a very long payback on a £12,000 job.
- Treating a heat pump as an automatic jump. It should cut carbon, but today's score is built on fuel cost and electricity costs more per unit than gas. Ask for the rating to be modelled.
- Reaching B in a listed building, or a conservation area home with restricted changes. If a large share of your options are ruled out, stopping at C is sensible. See what a conservation area means.
Why the target may shift
New-style EPCs are planned for the second half of 2027, with four headline measures in place of a single rating. The current rating is due to stay on certificates until at least the end of 2029, and eventually be removed.
This matters more at C and B than anywhere else, because you may be paying for a letter that is about to stop being the headline. Under current proposals, a home relying on a fossil fuel boiler could not score C on the heating measure, however good its current rating, while a heat pump would always score C or above. Band boundaries are not final.
If you are doing this work for comfort and lower bills, the change makes little difference. If you are doing it only for a B on the certificate, it is worth waiting for the final details before a major spend.
Help with the cost
The Warm Homes: Local Grant does not apply, because it is for homes rated D to G. The Boiler Upgrade Scheme offers £7,500 towards a heat pump in England and Wales, or £9,000 for eligible oil or LPG homes without mains gas until March 2027, and no longer requires an EPC. Warm Homes loans can cover solar, batteries and heat pumps. Qualifying installations are zero rated for VAT until 31 March 2027.
Questions, answered
Is B much better than C?
On the current scale, B starts at 81 and C at 69. A home at the top of C and one at the bottom of B are almost identical, so check the score, not just the letter.
Can a Victorian house get a B?
It can happen, but it usually needs wall insulation, good heating and solar panels together. Many older homes will not reach it at a sensible cost, and the walls may need specialist advice.
Should I wait for the new EPC before doing work?
For comfort and bills, there is no need to wait. If the rating is your only goal, waiting for the final measures is reasonable. A launch date for new-style EPCs had not been confirmed when we checked.