EPC C Upgrade Planner: Cost Your Route to Band C

Upgrade planner

Build your route to C

Tick the measures that apply. Costs are indicative 2026 UK ranges for a typical 2–3 bed home; always get quotes.

Loft insulation top-up to 270 mmCheap, quick and one of the best points-per-pound upgrades. fabric £500–£1,200 Cavity wall insulationCheck the wall is suitable first; exposure and existing fill matter. fabric £1,500–£3,500 Draught-proofing doors, windows and hatchesLow cost and tenants notice it straight away. fabric £200–£700 Suspended timber floor insulationBest done at void periods when carpets are up. fabric £1,500–£4,000 Replace single glazing with double/tripleWorth doing where glazing is single or failed; otherwise low priority. fabric £4,000–£9,000 Internal wall insulation (per external room)Needs careful moisture detailing. Use a PAS 2035 route. fabric £2,500–£5,000 External wall insulation (whole house)Big impact, big cost. Check planning and grant eligibility. fabric £10,000–£20,000 Heating controls: programmer, room stat, TRVsA small, cheap gain that also cuts tenant bills. heating £250–£600 Insulated hot water cylinder and pipeworkA jacket costs pennies; a new cylinder costs more but helps. heating £50–£900 Efficient condensing boiler replacementOnly where the old boiler is non-condensing or failing. heating £2,500–£4,500 High heat-retention storage heatersOften the best move for flats without gas. heating £2,500–£5,000 Air source heat pump (after £7,500 grant)Boiler Upgrade Scheme can fund £7,500. Fabric first so it runs well. heating £1,500–£7,000 Solar PV (3–4 kWp)Strong on smart readiness and tenant bills where the roof suits. smart £5,000–£7,500 Home battery storagePairs with PV and time-of-use tariffs. smart £3,000–£6,000 Smart meterFree from the energy supplier. Ask your tenant to book it. smart Free Low-energy lighting throughoutTiny cost, and it removes an easy EPC recommendation. fabric £50–£200

Estimated cost£0

Typical impact—

Against a £10,000 cap

Start with fabric: it is the primary test and where cap spend must go first.

Questions

Common questions

How accurate are the costs?

They are indicative 2026 ranges for a typical 2–3 bedroom home. Your EPC recommendations and installer quotes give real figures.

Why fabric first?

The 2030 rules make fabric performance the primary test, and insulation lets any new heating system run efficiently.

Sources

Checked 18 September 2026. Regulations can change: always confirm on GOV.UK.

Keep reading

Upgrade guideThe measures, costs and order of works.Cost cap calculatorThe most you'll have to spend.GrantsFunding that cuts the cost of reaching C.New EPC metricsFabric, heating and smart readiness explained.

Build your route to band C, and see what it costs.