How to improve your rental property's EPC rating, and what it actually costs

In England and Wales, today’s binding private-rented-sector MEES floor is EPC E with a £3,500 cost cap; EPC C by 1 October 2030 and a £10,000 cap are government policy but still need legislation. Scotland and Northern Ireland run separate EPC regimes, so the England-and-Wales figures below should not be treated as UK-wide law.

What actually improves an EPC rating?

Insulation, heating and hot-water upgrades, low-energy lighting, better glazing and solar PV are the main works that improve an EPC rating, but the score only moves when the assessor’s data is run through the approved EPC methodology. Government landlord guidance introduces its improvement table by saying, “These measures will improve the energy performance of your dwelling,” and that table includes fabric, heating, lighting and generation measures. In practice, the cheapest route from EPC D to C is usually fabric first: loft insulation, cavity wall insulation where suitable, heating controls, low-energy lighting and only then bigger-ticket items such as solar PV, wall insulation or heating-system replacement. EPC C for rented homes is not yet law: government says it will legislate and introduce “a single compliance date of 1 October 2030,” with a future £10,000 cap, while today’s enforceable minimum remains EPC E and the current statutory cap is £3,500.

Do you have to do the improvements your EPC recommends?

You do not have to follow your EPC’s recommended improvements in the listed order, but a rented home in England and Wales must meet the legal MEES floor or have a valid exemption. The current law defines the “minimum level of energy efficiency” for a domestic private rented property as “an energy performance indicator of band E,” and the letting ban says, “A landlord of a sub-standard domestic PR property must not let the property unless regulation 25, or one or more of the exemptions in Chapter 4, applies.” The EPC recommendations are a route, not a binding shopping list: the MEES rules also recognise improvements identified in “a green deal report, a recommendation report, or a report prepared by a surveyor.” EPC C and the £10,000 cap are planned, not current law; today’s enforceable cap is still £3,500 including VAT.

Does cavity wall insulation improve an EPC rating?

Cavity wall insulation can improve an EPC rating where the property has suitable unfilled cavity walls, and it is formally recognised as an energy-efficiency improvement. The statutory list of qualifying measures includes “cavity wall insulation,” and government landlord guidance treats it seriously enough that a wall-insulation exemption applies where the only remaining relevant improvements are “cavity wall insulation, external wall insulation, or internal wall insulation.” It is not automatically the best or safest measure for every property: exposed locations, damp history, poor brickwork or unsuitable cavities can make it risky, and the EPC gain depends on the existing wall construction recorded by the assessor. Where the wall is suitable, though, cavity fill is usually one of the cheaper fabric upgrades that can move a rental from EPC E or D toward C before landlords reach higher-cost measures.

How many EPC points does loft insulation add?

Standard loft insulation adds an average of 4.9 EPC points, but the actual gain depends on the existing depth, roof type and the rest of the property’s RdSAP calculation. Propertymark reports: “Standard loft insulation can add an average of 4.9 points, however, it is ‘room in roof’ insulation (+9.91 points) that is the most effective measure when it comes to improving an EPC score.” That average is useful for judging whether loft insulation might move a property from D to C, but it is not a statutory points allowance and it is not guaranteed on your certificate. A cold loft with little or no insulation can gain materially; a loft already near modern standards may gain very little. Room-in-roof insulation can be a much bigger EPC lever because it tackles a larger heat-loss area.

How thick should insulation be in a rented property?

When qualifying loft insulation work is undertaken in England, Approved Document L’s example construction is 250mm mineral or cellulose fibre quilt, not the 270mm figure often repeated online. The 2026 Approved Document L table says: “Provide loft insulation – 250mm mineral fibre or cellulose fibre as a quilt laid between and across ceiling joists or loose fill or equivalent.” That is a building-regulations guidance route for meeting the target U-value when the relevant roof or ceiling work is being done; it is not a standing rule that every existing rented property must already contain 250mm. The important correction is that 270mm is not the general legal minimum for rented homes. If a landlord is topping up a cold loft for EPC improvement, the practical target is to reach the required thermal performance, with 250mm mineral or cellulose quilt as the stated example.

Will external wall insulation make your property harder or more expensive to insure?

External wall insulation can make a property harder or more expensive to insure if insurers see the system, render, workmanship or water-ingress risk as material, and the NAO’s defect finding makes that a real underwriting concern. The National Audit Office found that “98% of homes with external wall insulation have major issues requiring remediation (between 22,000 and 23,000 homes)” under two government schemes it audited. There is no special statute that says external wall insulation must attract a premium loading, but the general insurance rule still matters: “It is the duty of the consumer to take reasonable care not to make a misrepresentation to the insurer.” A landlord should disclose external wall insulation accurately, keep guarantees and installation records, and expect insurers to differ. The risk is less the EPC measure itself than damp, trapped moisture, poor detailing and claims history.

Will a new boiler improve your EPC rating?

A new boiler can improve an EPC rating if it replaces an inefficient heating system, but there is no fixed EPC-points award for a boiler swap. The EPC must show the rating “calculated and expressed in accordance with the methodology approved by the Secretary of State,” and government guidance explains that after assessment “the data is fed into a government approved software programme.” That means the result depends on the old boiler, controls, fuel, hot-water setup, insulation and the rest of the dwelling. A condensing gas boiler with good controls may help an EPC E or D property, but it is often not the cheapest first move if the loft is under-insulated, the lighting is old, or heating controls are missing. For a landlord chasing EPC C, a boiler should be priced against cheaper fabric and controls work before committing.

Does a heat pump improve your EPC rating?

A heat pump can improve, fail to improve, or even lower an EPC score under the current England-and-Wales rating because the headline EPC metric is cost-based and electricity is priced above gas. DESNZ states: “For instance, installing a heat pump could reduce the EER due to the higher relative cost of electricity compared to gas, despite heat pumps being an efficient low-carbon heating solution.” That is the key trap: a heat pump may cut carbon and run efficiently, but the EPC’s energy-efficiency rating is not a pure carbon score. DESNZ also says, “A cost-based metric may not incentivise switching from fossil fuel heating to low-carbon alternatives.” The Boiler Upgrade Scheme can pay “£7,500 towards an air source heat pump” in England and Wales, but landlords should model the EPC result before assuming a heat pump will deliver EPC C.

How do you improve an EPC rating when the heating is electric?

With electric heating, the usual EPC route is to reduce demand first and then replace direct-acting heaters with better-scoring electric systems such as high-heat-retention storage heaters where suitable. BRE explains the problem plainly: “Electricity is a relatively expensive fuel (around 3 to 4 times the price of mains gas), so even though all direct electric heaters are 100% efficient, the use of electric heating usually results in poor ratings.” It adds that “electric storage heaters can make use of cheaper electricity available at nighttime, so usually result in a better EPC rating than direct electric heaters.” For landlords, that means loft insulation, wall insulation where suitable, draught reduction, hot-water controls and lighting still matter, but panel heaters are often the drag. Storage heaters affect EPC ratings because RdSAP credits the cheaper tariff assumptions where the installation qualifies.

Does a log burner or other secondary heater change an EPC rating?

A fixed log burner or other fixed secondary heater can change an EPC rating because RdSAP records secondary heating where a fixed emitter is present. The MHCLG-approved RdSAP convention says: “Include if fixed emitter present regardless of whether main system(s) heat all rooms.” That means a log burner is not ignored merely because the main heating system already covers the habitable rooms. The effect can be positive or negative depending on the fuel, efficiency and what the assessor records; it is not safe to install a stove just to chase an EPC point without modelling it. If two secondary heaters heat the same number of habitable rooms, the assessor should apply the RdSAP conventions rather than pick the one the owner prefers. In rented homes, stove safety, ventilation, flues, maintenance and insurance can matter as much as the EPC score.

How much do solar panels change an EPC rating?

Solar panels usually improve an EPC rating, but there is no reliable single points figure because RdSAP scores the whole dwelling and only counts PV that serves that specific property. The RdSAP convention says: “In all cases, the PV-generated electricity is included in the assessment of a dwelling only if the dwelling has a PV generation meter serving it.” Government’s own worked example reaches B83 after “solar photovoltaic panels,” but it warns that “The performance ratings after improvements listed below are cumulative,” so that result includes earlier insulation, glazing and heating upgrades rather than solar alone. A specialist EPC site describes the effect as “moderate but positive,” which is a fair market summary. For landlords, solar PV is often a later-stage EPC C measure after cheaper demand-reduction works, unless the property has poor electric heating economics or unusually good roof economics.

How do you improve the EPC rating of a flat?

A flat’s EPC rating is usually improved through heating, controls, lighting, hot-water efficiency and any insulation the landlord can actually control, because flats often lack the simple loft and wall options available to houses. EPC Advisor notes the common limitation: “You live in a top-floor flat with no individual loft space.” In blocks, the lease may also restrict external wall insulation, windows, roof works or solar panels, so a landlord should separate works they can instruct alone from works needing freeholder or management-company consent. For electrically heated flats, replacing old storage heaters can be one of the more realistic upgrades; the market view is that “upgrading to more modern high-heat-retention units or – where appropriate – efficient electric systems can make a notable EPC difference.” The legal cost cap still matters: for today’s EPC E floor, government says install what fits within £3,500 and then register an exemption if needed.

What grants are there to help pay for EPC improvements?

The main live grants or subsidy routes are ECO4 for eligible low-rated homes, the Boiler Upgrade Scheme for heat pumps in England and Wales, and Warmer Homes Scotland for Scotland. ECO says: “If you rent from a private landlord, the house must have an energy efficiency rating of E, F or G to be eligible,” and it may help with “insulation work, for example to your loft or cavity walls.” The Boiler Upgrade Scheme is “open to people in England and Wales,” can apply to “a property you rent out to tenants,” and pays “£7,500 towards an air source heat pump.” The Great British Insulation Scheme has ended for new installations because “Installations must be complete by 31 March 2026, when the scheme ends.” Scotland’s separate Warmer Homes Scotland route says eligible homeowners and private rented sector tenants could receive “£10,000 or more” for heating or insulation.

What does it cost to bring a rental up to EPC C?

Government modelling puts average landlord spend to reach the planned EPC C standard at £5,400 per property, but the legal EPC C duty and £10,000 cap are not yet in force. The impact assessment says: “Average landlord costs follow the same pattern: £3,200 under Option 1 versus £5,400 under Options 2 and 3.” A separate DESNZ figure for D-to-C modelling says the “average cost of improving a PRS property from EER D to EER C” is around £6,000. The spread matters: a D-rated flat needing heater upgrades may be much cheaper than a solid-wall Victorian terrace needing wall insulation, roof work and damp remediation. Today’s enforceable rule is still EPC E, and government guidance says: “The cost cap: you are not currently required to spend more than £3,500 (including VAT) on energy efficiency improvements.” The planned future cap is £10,000 with 10-year exemptions.

What does an EPC E cost per month to run, compared with a C?

Government modelling says moving rented homes to EPC C saves tenants an average £210 a year by 2030, which is about £17.50 a month. The impact assessment states: “Our analysis projects that, under the final MEES EPC C policy design, tenant households in upgraded properties will save an average of £210 annually on energy bills by 2030 (based on projected 2030 energy prices, adjusted to 2025 pounds).” That is an average policy-model figure, not a promise that every EPC E home costs exactly £17.50 more per month than an EPC C home. Actual bills depend on property size, occupancy, tariff, heating fuel, thermostat use and weather. For landlords, the important point is that much of the financial benefit of EPC upgrades appears in the tenant’s energy bill, not directly in the landlord’s rent account.

Should you spend more than the £10,000 cap, or claim an exemption instead?

EPC C and its £10,000 cap are not law yet: DESNZ still needs an Act of Parliament and a statutory instrument, aimed for 2027, with the new standard planned for 1 October 2030; today’s binding floor is EPC E at £3,500. Government says it will “proceed with introducing new powers by Act of Parliament,” will introduce “a single compliance date of 1 October 2030,” and will raise “the cost-cap to £10,000 with a 10-year validity period for exemptions.” Once that regime exists, DESNZ says: “If the property does not meet the standard after £10,000 has been invested, the landlord may register the property for an exemption valid for 10 years and continue to let the property during this time.” Spending £12,400 now only makes sense if it also protects capital value, avoids later disruption, fixes real defects, or improves rentability.

What is the landlord tenant dilemma?

The landlord-tenant dilemma is the split-incentive problem where the landlord pays for energy-efficiency work but the tenant receives most of the bill saving. DESNZ describes the private-rented-sector problem as including “the split incentive between landlords and tenants.” That is why voluntary upgrades often stall: a landlord may face thousands of pounds of upfront cost, while the direct saving appears on the tenant’s gas or electricity bill. The phrase is policy and economics language, not a statutory term that creates a separate duty. It explains why MEES exists and why EPC C is being pursued through regulation rather than relying only on market demand. It also explains the cash-flow tension for landlords: the works may be rational for the building and tenant, but still unattractive if rent, sale value or finance savings do not recover the cost.

Is it worth doing the work, or better to sell the property as it is?

Whether it is worth doing EPC work before selling depends on the discount a buyer demands, but government modelling says a D-to-C upgrade can take about 12 years for a landlord to recoup through rent premium alone. DESNZ says that a “yearly return compares to an average cost of improving a PRS property from EER D to EER C of around £6,000,” meaning “it would take around 12 years for the landlord to recoup their investment cost.” It also says that, given that payback and opportunity cost, “it is unlikely that the landlord in this scenario would proceed with the upgrades.” Selling as a fixer-upper shifts EPC, damp, roof and refurbishment risk to the buyer but usually crystallises a discount. Doing the work first makes more sense where it also solves defects, widens mortgageability, reduces negotiation risk and lets the property sell as lettable stock.

How do you get your EPC updated once the work is done?

You update an EPC in England and Wales by commissioning a new EPC assessment; a registered EPC cannot simply be edited. The regulations say a registered certificate “shall not be altered once registered,” and an EPC remains valid only where “no other energy performance certificate for the building has since been entered on the register.” In practice, the new certificate replaces the old one for marketing and compliance purposes. Use the government assessor-finder and “contact them directly to arrange a viewing”; there is no separate administrative renewal route after works. Scotland has “a different process if you want to find an accredited assessor in Scotland,” and Scottish EPCs are valid for “10 years from the date on which it was issued.” Northern Ireland also requires an accredited assessor visit: “An EPC can only be produced by an accredited energy assessor who will visit the property to carry out an assessment.”

Last reviewed September 2026.

Sources

• GOV.UK MEES landlord guidance — “These measures will improve the energy performance of your dwelling.” Source
• Energy Efficiency (Private Rented Property) (England and Wales) Regulations 2015, regulation 24 — “the cost cap” means £3,500 less— Source
• DESNZ, Improving the energy performance of privately rented homes: government response — “introducing a single compliance date of 1 October 2030 for the new standard” Source
• Energy Efficiency (Private Rented Property) (England and Wales) Regulations 2015, regulation 22 — “minimum level of energy efficiency”, in relation to a domestic PR property and a non-domestic PR property, means an energy performance indicator of band E Source
• Energy Efficiency (Private Rented Property) (England and Wales) Regulations 2015, regulation 23 — “A landlord of a sub-standard domestic PR property must not let the property unless regulation 25, or one or more of the exemptions in Chapter 4, applies.” Source
• Energy Efficiency (Private Rented Property) (England and Wales) Regulations 2015, regulation 24 — “a green deal report, a recommendation report, or a report prepared by a surveyor” Source
• Energy Efficiency Regulations 2012, Schedule — “cavity wall insulation” Source
• GOV.UK MEES landlord guidance — “Register this exemption if the only relevant improvements for your property are: cavity wall insulation, external wall insulation, or internal wall insulation (for external walls)” Source
• Propertymark — “Standard loft insulation can add an average of 4.9 points, however, it is ‘room in roof’ insulation (+9.91 points) that is the most effective measure when it comes to improving an EPC score.” Source
• Approved Document L 2026 — “Provide loft insulation – 250mm mineral fibre or cellulose fibre as a quilt laid between and across ceiling joists or loose fill or equivalent” Source
• National Audit Office, energy efficiency installations report — “98% of homes with external wall insulation have major issues requiring remediation (between 22,000 and 23,000 homes).” Source
• Consumer Insurance (Disclosure and Representations) Act 2012, section 2 — “It is the duty of the consumer to take reasonable care not to make a misrepresentation to the insurer.” Source
• Energy Performance of Buildings Regulations 2012, regulation 9 — “calculated and expressed in accordance with the methodology approved by the Secretary of State” Source
• GOV.UK EPC guide — “Once the assessment is completed the data is fed into a government approved software programme.” Source
• DESNZ, Reforms to the energy performance of buildings regime — “For instance, installing a heat pump could reduce the EER due to the higher relative cost of electricity compared to gas, despite heat pumps being an efficient low-carbon heating solution.” Source
• DESNZ, Reforms to the energy performance of buildings regime — “A cost-based metric may not incentivise switching from fossil fuel heating to low-carbon alternatives because of the effects of the relationship between fuel prices incorporated within the methodology.” Source
• GOV.UK Boiler Upgrade Scheme — “£7,500 towards an air source heat pump (sometimes called an air-to-water heat pump)” Source
• BRE SAP 2012 — “Electricity is a relatively expensive fuel (around 3 to 4 times the price of mains gas), so even though all direct electric heaters are 100% efficient, the use of electric heating usually results in poor ratings.” Source
• BRE SAP 2012 — “However, electric storage heaters can make use of cheaper electricity available at nighttime, so usually result in a better EPC rating than direct electric heaters.” Source
• RdSAP conventions v12.2 — “Include if fixed emitter present regardless of whether main system(s) heat all rooms.” Source
• RdSAP conventions v12.2 — “In all cases, the PV-generated electricity is included in the assessment of a dwelling only if the dwelling has a PV generation meter serving it.” Source
• GOV.UK MEES landlord guidance — “The performance ratings after improvements listed below are cumulative, that is, they assume the improvements have been installed in the order that they appear in the table.” Source
• EPC Advisor — “Solar PV tends to have a moderate but positive effect on EPC scores.” Source
• EPC Advisor — “You live in a top-floor flat with no individual loft space.” Source
• EPC Advisor — “For flats with old electric night storage heaters, upgrading to more modern high-heat-retention units or – where appropriate – efficient electric systems can make a notable EPC difference.” Source
• GOV.UK Energy Company Obligation — “If you rent from a private landlord, the house must have an energy efficiency rating of E, F or G to be eligible.” Source
• GOV.UK Energy Company Obligation — “You may get help with the cost of: insulation work, for example to your loft or cavity walls” Source
• GOV.UK Boiler Upgrade Scheme — “This scheme is open to people in England and Wales.” Source
• GOV.UK Boiler Upgrade Scheme eligibility — “own the property you're applying for (including if it's a business, a second home, or a property you rent out to tenants)” Source
• GOV.UK Great British Insulation Scheme — “Installations must be complete by 31 March 2026, when the scheme ends.” Source
• Home Energy Scotland — “Eligible homeowners and private rented sector tenants could receive £10,000 or more of funding for energy efficiency improvements like heating or insulation.” Source
• DESNZ impact assessment — “Average landlord costs follow the same pattern: £3,200 under Option 1 versus £5,400 under Options 2 and 3.” Source
• DESNZ impact assessment — “average cost of improving a PRS property from EER D to EER C of around £6,000” Source
• GOV.UK MEES landlord guidance — “The cost cap: you are not currently required to spend more than £3,500 (including VAT) on energy efficiency improvements.” Source
• DESNZ impact assessment — “Our analysis projects that, under the final MEES EPC C policy design, tenant households in upgraded properties will save an average of £210 annually on energy bills by 2030 (based on projected 2030 energy prices, adjusted to 2025 pounds).” Source
• DESNZ, Improving the energy performance of privately rented homes — “Government will proceed with introducing new powers by Act of Parliament” Source
• DESNZ, Improving the energy performance of privately rented homes — “raising the cost-cap to £10,000 with a 10-year validity period for exemptions” Source
• DESNZ government response — “If the property does not meet the standard after £10,000 has been invested, the landlord may register the property for an exemption valid for 10 years and continue to let the property during this time.” Source
• DESNZ impact assessment — “the split incentive between landlords and tenants” Source
• DESNZ impact assessment — “it would take around 12 years for the landlord to recoup their investment cost.” Source
• DESNZ impact assessment — “it is unlikely that the landlord in this scenario would proceed with the upgrades.” Source
• Energy Performance of Buildings Regulations 2012, regulation 27 — “shall not be altered once registered.” Source
• Energy Performance of Buildings Regulations 2012, regulation 9 — “no other energy performance certificate for the building has since been entered on the register.” Source
• GOV.UK, Find an energy certificate assessor — “contact them directly to arrange a viewing” Source
• GOV.UK, Find an energy certificate assessor — “There is a different process if you want to find an accredited assessor in Scotland.” Source
• Energy Performance of Buildings (Scotland) Regulations 2008, regulation 6 — “An energy performance certificate for a building is valid for a period of 10 years from the date on which it was issued.” Source
• nidirect — “An EPC can only be produced by an accredited energy assessor who will visit the property to carry out an assessment.” Source