If your EPC rating is holding you back from selling, remortgaging or renting out your property – or you just want lower energy bills – the good news is that EPC ratings can be improved.
This guide walks through 27 proven ways to improve your EPC rating, grouped by budget and impact. You’ll see which upgrades are free, which cost a few hundred pounds, and which are larger investments that can transform your rating.
- Understand how EPC ratings work and what affects your score
- See quick wins you can do this week – even on a £0 budget
- Compare upgrade options by cost, savings and EPC point impact
- Learn which improvements make sense for your type of home
To see personalised recommendations based on your actual EPC data, start by using our free EPC checker and opening your property report.
How EPC ratings work (in plain English)
An Energy Performance Certificate (EPC) rates your property’s energy efficiency from A (most efficient) to G (least efficient). The underlying SAP score (0–100+) looks at:
- How well your home is insulated
- How efficient your heating system is
- How much heat escapes through windows and doors
- How much you rely on fossil fuels vs renewables
Your EPC shows:
- A current rating (e.g. D 60)
- A potential rating if recommended improvements are completed
- A list of recommended measures with estimated cost and savings
For a fuller explainer, see What is an EPC? A Complete Guide for Landlords and our support guide Is My EPC Still Valid?.
The key point: you improve your EPC by reducing the energy needed to heat and power your home, and by switching to more efficient systems.
Before you start: check your current EPC
Before spending money, it’s worth understanding where you are today.
- Use our EPC checker to find your property by postcode.
- Open your property report to see current and potential ratings.
- Review the recommended measures and their EPC point impact.
You can then use this guide to prioritise upgrades that:
- Fit your budget
- Deliver the biggest EPC point gain
- Make sense for your property type (flat vs detached, Victorian vs new build, etc.)
Quick wins (£0–£100): improvements you can make this month
These changes are either free or low-cost and can help you squeeze extra points from your existing setup.
1. Switch to LED lighting
Replacing old halogen and incandescent bulbs with LEDs is one of the fastest, cheapest energy upgrades.
- Typical cost: £2–£5 per bulb
- Savings: £40–£80 per year for a typical house
- EPC impact: Small but positive, especially if you still have lots of halogens
Many EPCs specifically mention “Low energy lighting” as a factor. Moving from partial to near-100% LED coverage can help on the margins.
2. Draught proof doors, windows and chimneys
Warm air escaping through gaps is wasted energy.
- Use brush strips, sealant and keyhole covers on doors and windows
- Consider a chimney balloon or draught excluder for open chimneys
- Fit letterbox brushes to reduce cold air ingress
Typical cost: £30–£100, with savings of £20–£50 per year and a more comfortable home. Draught proofing indirectly supports other measures like insulation and boiler upgrades by making them more effective.
3. Optimise heating controls
Smart thermostats and better controls don’t directly change your EPC fuel type, but they can lower your heating demand:
- Lower your target temperature by 1°C
- Use programmed schedules so you’re not heating an empty home
- Fit thermostatic radiator valves (TRVs) to control individual rooms
Adding or upgrading heating controls is often a recommended EPC measure. It can add a few SAP points for relatively low cost.
4. Bleed radiators and balance the system
If your radiators have cold spots, your boiler is working harder than it needs to.
- Bleeding radiators is a DIY job using a simple key
- A professional system balance can ensure even heat distribution
The EPC impact is indirect, but this is a good no-regrets step before considering larger upgrades.
For even more free and low-cost changes, see: Cheapest Ways to Improve Your EPC Rating.
Budget improvements (£100–£1,000)
Once you’ve done the quick wins, the next tier of improvements involve slightly more spend but often give better EPC point gains.
5. Top up loft insulation
Heat rises. If your loft is under-insulated, you’re losing a lot of warmth.
- Recommended depth: 270mm of mineral wool insulation
- Typical cost: £300–£600 for a standard house (DIY can be cheaper)
- Savings: £150–£250 per year depending on size and fuel type
- EPC impact: Often +5–10 SAP points
If your EPC mentions “Loft insulation (200mm or less)”, topping up can be one of the best-value upgrades available. Read more in Does Loft Insulation Improve Your EPC?.
6. Insulate hot water cylinder and pipes
If you have a hot water tank, ensuring it’s properly insulated reduces heat loss.
- Fit a compliant cylinder jacket if one isn’t already present
- Lag exposed hot water pipes in the airing cupboard and near the boiler
This is a low-cost upgrade (£30–£80) that can support a higher EPC score, especially in older systems.
7. Improve floor insulation (where accessible)
For suspended timber floors, adding insulation between joists can help:
- Typical cost: £400–£1,000 depending on access
- Savings: Moderate; EPC point gains can be noticeable in draughty homes
This is more invasive than loft insulation but may be recommended in EPC reports for period properties and ground-floor flats.
Mid-range upgrades (£1,000–£5,000)
These measures have higher upfront costs but deliver substantial EPC improvements – often enough to move you from one band to the next.
8. Cavity wall insulation
If your property has unfilled cavity walls, this is often the single biggest EPC win per pound spent.
- Typical cost: £800–£1,500
- Savings: £150–£300 per year
- EPC impact: Often +10–15 SAP points
Not all homes are suitable (e.g. some exposed or hard-to-treat walls), so you’ll need a survey. But where possible, cavity wall insulation is a cornerstone of EPC improvement.
9. Upgrade old single glazing to double glazing
New windows are expensive, but in some homes they play a major role in heat loss and comfort.
- Typical cost: £3,000–£6,000+ depending on property and openings
- Savings: Moderate, but noticeable comfort gains and noise reduction
- EPC impact: Can help move borderline properties up a band
If budget is tight, consider targeted upgrades (e.g. worst rooms first) or alternatives like secondary glazing. A dedicated guide on windows and EPC is planned; for now, weigh this against cheaper insulation and boiler options first.
10. Replace old electric storage heaters (flats)
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.
- EPC methodology is sensitive to heating type and controls
- In some cases, switching to modern panel heaters with smart controls can be beneficial
If you’re in this situation, it’s worth speaking to a qualified assessor to model options before committing.
Major renovations (£5,000+): heating systems, heat pumps and renewables
The biggest EPC gains often come from tackling heating systems and adding renewables. These are significant investments but can transform a G–E property into a C–B home, especially when combined with insulation.
11. Install a new, efficient gas boiler
If you currently have an old non-condensing boiler, replacing it with a modern A-rated condensing boiler can:
- Improve boiler efficiency into the 90%+ range
- Reduce gas use and bills
- Contribute several EPC points – especially when combined with good controls
Our dedicated article explains this in depth: Does a New Boiler Improve Your EPC?. For detailed pricing, see New Boiler Cost UK (2025 Guide), and if your EPC recommends a boiler upgrade you can explore quotes via our boiler partner journey.
12. Add an air source heat pump
Where the property is well insulated, an air source heat pump can be a strong EPC win and significantly cut carbon emissions.
- Best suited to well-insulated homes with sized radiators or underfloor heating
- Works particularly well when paired with low-temperature heating and smart controls
- Eligible for grants under schemes like the Boiler Upgrade Scheme
We explore costs and grants in Air Source Heat Pump Costs UK and compare against gas boilers in Boiler vs Heat Pump: Cost Comparison.
13. Install solar PV panels
Solar panels don’t directly reduce the heat needed for your home, but they offset electricity use, which can lift your EPC rating.
Key benefits:
- Generate your own electricity during daylight hours
- Lower your bills, especially if you’re home during the day or have battery storage
- Improve the EPC’s “Environmental Impact” rating
See Solar Panels and EPC Rating for a focused breakdown of costs, savings and rating impact.
14. External or internal wall insulation (solid walls)
For solid-walled properties (often Victorian and older), solid wall insulation can have a dramatic effect on heat loss – but it’s a major project.
- External wall insulation: typical cost £8,000–£15,000+
- Internal wall insulation: often cheaper but more disruptive to internal space
If you own a period property, also read How to Improve EPC on Victorian House for heritage-sensitive options.
Comparing improvement options: cost vs EPC point gain
Every property is different, but as a rule of thumb:
- Best £ per EPC point tends to be: loft insulation top-ups, cavity wall insulation, draught proofing and heating controls.
- Medium £ per point: boiler upgrades (from very old to modern), some floor insulation measures.
- High £ per point but high impact: heat pumps, solar PV, solid wall insulation.
Your EPC report will list each recommended measure with a potential point gain. Use that as a starting point and then cross-check with:
- Cheapest Ways to Improve Your EPC Rating
- How Much Does It Cost to Improve EPC Rating? – boiler-specific but very cost-focused
- Home Energy Grants UK 2025 (coming soon) for funding options
Which improvements are right for your property?
Not every recommendation makes sense for every home. A sensible sequence is:
- Check your current EPC using our EPC checker.
- Tackle quick wins and low-cost insulation first.
- Only then consider bigger investments like windows or heating systems.
- For Victorian or heritage homes, read How to Improve EPC on Victorian House before committing to invasive works.
- If you’re a landlord, cross-check against EPC Rules for Landlords 2025–2030 to prioritise compliance.
Our property reports are designed to mirror this logic, ranking improvements by impact, cost and disruption. Learn more about how we prioritise recommendations in our methodology.
Grants and funding for EPC improvements
Depending on your circumstances, you may be able to reduce costs using:
- National schemes such as ECO4 and the Boiler Upgrade Scheme
- Local authority grants for insulation and low-carbon heating
- Supplier-funded offers (e.g. free or discounted loft and cavity wall insulation)
We cover this in detail in Home Energy Grants UK 2025: Complete Guide to Funding (/insights/home-energy-grants-uk – cluster 6). Where grants aren’t available, you might still improve affordability by:
- Bundling works (e.g. insulation + boiler) to reduce labour costs
- Getting multiple quotes via specialist installers
If your EPC specifically recommends a new boiler, you can compare prices and finance options via our boiler partner route – see New Boiler Cost UK (2025 Guide) for typical price ranges.
FAQs
What improves EPC rating the most?
It depends on your starting point, but common high-impact upgrades include:
- Cavity wall insulation (where suitable)
- Loft insulation top-ups in poorly insulated homes
- Replacing very old boilers with efficient condensing models
- Adding low-carbon heating (heat pumps) in well-insulated properties
- Solid wall insulation in older, hard-to-treat homes
Your EPC recommendations panel is the best place to see which of these will make the biggest difference for your specific property.
How can I improve my EPC rating cheaply?
Start with free and low-cost measures:
- Swap to LED lighting in all rooms
- Draught proof around doors, windows and chimneys
- Optimise heating controls and thermostats
- Add or upgrade hot water cylinder insulation
Then move on to budget-friendly insulation (especially loft and cavity walls). For a dedicated budget guide, see Cheapest Ways to Improve Your EPC Rating.
Will a new boiler improve my EPC?
Often yes – especially if you’re replacing a non-condensing or very old boiler with a modern A-rated model. The exact impact depends on your starting rating, property type and controls. We cover this in detail in Does a New Boiler Improve Your EPC?.
Do solar panels improve EPC ratings?
Yes. Solar PV can improve the EPC by offsetting your electricity usage with on-site generation. The effect is more noticeable for properties that use a lot of electricity or electric heating. For a focused breakdown, read Solar Panels and EPC Rating.
How do I know if I’ve reached the next band?
Your EPC shows both your current band and your potential band. After major improvements, you’ll need a new EPC assessment to confirm your new rating. Use Is My EPC Still Valid? to check whether you also need to renew your certificate.
When you’re ready, head back to the EPC checker to view your property’s recommendations and start planning which of these 27 improvements will move you towards your target EPC band.
You don’t have to spend thousands on heat pumps or new windows to improve your EPC rating. In many homes, simple, low-cost changes can move you up a band – or at least get you much closer.
This guide focuses on the cheapest ways to improve your EPC rating, from free behavioural tweaks to upgrades under £500. It’s the budget-friendly companion to our main guide: 27 Ways to Improve Your EPC Rating.
- Start with free EPC improvements you can do today
- See which upgrades under £500 give the biggest EPC gain
- Understand where to draw the line and save larger works for later
Before you start, use our EPC checker to see your current rating and recommended improvements.
Step 1: Free EPC improvements (£0 spend)
These measures cost nothing except a bit of time and can still strengthen your EPC position – especially when combined.
1. Use your heating controls more efficiently
EPC assessments assume typical heating patterns, but poorly used controls can still hurt in practice:
- Set a realistic temperature (e.g. 19–20°C instead of 22–23°C).
- Use a timer or programmer so you’re not heating an empty home.
- Turn heating off in unused rooms if you have individual controls.
If your current EPC says you have “no time or temperature control”, consider adding them when budget allows – we cover that in the paid section below.
2. Close curtains and internal doors
This won’t directly change the EPC calculation, but it reinforces the effect of other measures by reducing heat loss.
- Close curtains at dusk to keep heat in.
- Shut doors between heated and unheated rooms.
These habits make your home feel warmer, which makes it easier to live comfortably at slightly lower thermostat settings.
3. Bleed radiators and balance your system
If radiators are cold at the top, your heating system is not running efficiently.
- Bleeding radiators is a simple DIY task using a radiator key.
- After bleeding, you may need to re-pressurise the boiler (follow the manual).
This can improve comfort and reduce wasted energy, particularly in older systems.
4. Find and fix obvious draughts (DIY-friendly)
From gaps under doors to unused chimneys, draughts waste heat you’ve already paid for.
- Use basic sealant or draught-excluder tape around leaky windows.
- Roll up a towel or use a draught excluder at the bottom of doors.
- Block open chimneys temporarily if they’re not in use (using safe, purpose-made products).
Once you know where the worst draughts are, you can tackle them more permanently when you have budget available.
For more free and £0–£50 ideas, see the quick-win section of 27 Ways to Improve Your EPC Rating.
Step 2: Low-cost upgrades under £100
These are high-ROI improvements that fit into most household budgets.
5. Swap to LED lighting throughout
If your EPC report mentions “Low energy lighting”, moving to 100% LEDs is an easy win.
- Replace remaining halogens and incandescents with LED bulbs.
- Prioritise rooms you use most (kitchen, living room, hallway).
Typical cost: £20–£80, with annual savings of £40–£80+ and a small EPC uplift.
6. Add hot water cylinder insulation
If your hot water cylinder doesn’t have a modern jacket:
- Fit a BS-compliant cylinder jacket (often around £25–£40).
- Lag nearby hot water pipes to reduce heat loss.
This is a classic low-cost measure that can appear in EPC recommendations, particularly in older homes with tanks.
7. Basic draught proofing kit
Upgrade your temporary draught fixes using inexpensive kits:
- Letterbox brush and draught-proof flap
- Rubber seals for door and window frames
- Foam strips around loft hatches
You can typically complete a small house for £50–£100.
Step 3: High impact under £500
Once you’ve tackled free and sub-£100 improvements, consider a few strategic upgrades under £500.
8. Loft insulation top-up (DIY or partial)
Full loft insulation jobs can cost more than £500, but you may be able to:
- Do a DIY top-up where safe, especially in easily accessible lofts.
- Focus on the worst areas first (thin or missing insulation).
Even partial improvements can reduce heat loss and support a better EPC score. For a full overview, see Does Loft Insulation Improve Your EPC?.
9. Upgrade heating controls
If your EPC indicates poor heating controls, improving them can be a cost-effective step:
- Install a room thermostat if you don’t have one.
- Add TRVs (thermostatic radiator valves) to key rooms.
- Consider a smart thermostat with scheduling and remote control.
Typical spend: £200–£500 depending on what’s already installed. Controls won’t fix a very old boiler, but they can squeeze more value from the system you have.
10. Improve floor insulation in targeted areas
You don’t have to insulate entire floors at once. Under suspended timber floors, you may be able to:
- Insulate accessible sections from below (e.g. from a cellar).
- Combine with other works (e.g. when lifting boards for plumbing).
Costs vary widely, but selective work can stay under £500 if access is simple.
When low-cost options aren’t enough
If you’re aiming to move from E to C or D to B, low-cost measures might not be sufficient on their own. In that case:
- Use our EPC checker to see how far your potential rating is from your current band.
- Read How to Improve EPC from D to C or How to Improve EPC from E to D for band-specific guidance.
- Consider mid-range upgrades like cavity wall insulation or a boiler replacement if recommended.
We also have specialist content for older homes: How to Improve EPC on Victorian House.
Low-cost doesn’t mean low quality
Low-cost EPC improvements are not about cutting corners. In many cases, they simply mean:
- Fixing obvious inefficiencies (draughts, missing insulation, poor controls).
- Getting the most from the heating system you already have.
- Doing preparatory work that makes future upgrades more effective.
From there, you can decide whether bigger investments like new boilers, heat pumps or solar panels are worthwhile:
- New Boiler Cost UK (2025 Guide)
- Does a New Boiler Improve Your EPC?
- Air Source Heat Pump Costs UK
- Solar Panels and EPC Rating
Check also whether you qualify for support under national or local schemes – see Home Energy Grants UK 2025 (/insights/home-energy-grants-uk) for an overview of grants and funding (cluster 6).
FAQs
What is the cheapest way to improve EPC rating?
The absolute cheapest ways are behavioural and DIY: using heating controls properly, draught proofing, LED lighting, and insulating hot water tanks. After that, loft insulation and cavity wall insulation often provide the best value for money per EPC point gained.
Can I improve my EPC rating without spending money?
You can make some progress through free actions – particularly if your current setup is very inefficient. But to move a full band (e.g. from E to D or D to C), you’ll almost always need to invest in insulation or heating upgrades. We cover the free-first approach in 27 Ways to Improve Your EPC Rating.
Is it worth spending money just to improve EPC?
It depends on your goals:
- Selling soon? A better EPC can make the property more attractive and support price negotiations.
- Landlord? You may need improvements to meet minimum standards – see EPC Rules for Landlords 2025–2030.
- Owner-occupier? Many EPC improvements also reduce bills and improve comfort, so you benefit directly.
What should I do next?
- Use the EPC checker to view your current rating and recommendations.
- Tick off all free and sub-£100 steps.
- Plan one or two sub-£500 upgrades that match your EPC recommendations.
- Revisit our main guide, 27 Ways to Improve Your EPC Rating, to plan medium and long-term improvements.
Taken together, these low-cost actions can make a surprisingly big difference to both your EPC rating and your monthly bills.
If your property is EPC band D, you’re in good company – it’s one of the most common ratings in England and Wales. But with rising energy costs and tighter rules on the horizon, many owners now want to get to band C.
The jump from D to C usually doesn’t require a full-scale renovation. Instead, it’s about choosing the right combination of insulation, heating and control upgrades – and doing them in the right order.
This guide focuses on:
- The cheapest options to move from D to C
- Typical costs and bill savings for each measure
- How to prioritise improvements using your EPC report
Before you start, look up your current EPC using our free EPC checker and open your property report.
Step 1: Understand your current D rating
Two different D-rated homes can have very different improvement paths.
Check your current and potential scores
On your EPC:
- Note the current SAP score (e.g. D 62).
- Note the potential SAP score if all recommended measures are completed (e.g. B 82).
The closer you already are to band C (69+), the fewer improvements you’ll need.
Review recommended measures
Your EPC lists recommended improvements, typically ordered by cost-effectiveness. Common examples include:
- Loft insulation top-up
- Cavity wall insulation
- Floor insulation (suspended floors)
- Heating controls upgrade
- New boiler or heat pump
- Solar panels or hot water improvements
We’ll now map these to typical costs and EPC impact so you can decide where to start.
Step 2: Low-cost upgrades that help push D towards C
These improvements alone might not move you a full band, but they set the stage and help on the margins.
1. Loft insulation top-up (if under-insulated)
If your loft has less than 270mm of insulation, topping up is often the first major step.
- Typical cost: £300–£600 (DIY or installer)
- Savings: £150–£250 per year
- EPC impact: Often +5–10 SAP points
For many D-rated homes, loft insulation plus one other major measure is enough to tip into C. Read more in Does Loft Insulation Improve Your EPC?.
2. Heating controls upgrade
If your EPC notes limited or missing controls, upgrades can be high-value:
- Add a room thermostat and programmer if you don’t have them.
- Install TRVs on radiators to control room-by-room temperatures.
- Consider a smart thermostat for more precise control.
Typical cost: £200–£500, with moderate EPC gains and immediate comfort improvements.
3. Targeted draught proofing
Especially in older homes, draughts around doors, windows and floors can lead to higher heating demand.
- Install draught-proof strips, letterbox brushes and chimney balloons (where appropriate).
- Seal obvious gaps using suitable products (avoid blocking essential ventilation).
These measures won’t transform your EPC on their own, but they improve the effectiveness of bigger upgrades.
For budget-first options, see Cheapest Ways to Improve Your EPC Rating.
Step 3: High-impact measures likely to move you from D to C
To gain a full band, most D-rated homes will need at least one of the following, sometimes in combination with low-cost steps.
4. Cavity wall insulation (where suitable)
If you have uninsulated cavity walls, this is often the single most effective upgrade for moving from D to C.
- Typical cost: £800–£1,500
- Savings: £150–£300 per year
- EPC impact: Often +10–15 SAP points
Check your EPC and property type. If it mentions “Cavity wall – no insulation (assumed)”, get a professional survey to confirm suitability and quote.
5. New A-rated gas boiler (from very old systems)
If your boiler is old and inefficient, replacing it with a modern condensing boiler can:
- Improve efficiency to 90%+
- Reduce gas usage and bills
- Deliver useful EPC gains, especially when paired with good controls
This is particularly relevant if your EPC shows your heating system as a weak point or recommends a boiler upgrade. Dive deeper in Does a New Boiler Improve Your EPC? and see price ranges in New Boiler Cost UK (2025 Guide).
6. Upgrading electric heating in flats
For electrically heated properties (e.g. with old storage heaters), moving towards:
- High-heat-retention storage heaters, or
- Efficient electric systems with smart controls
can trigger significant EPC changes due to how the calculation treats electric heating. Because this is complex and property-specific, it’s worth getting advice from an assessor or installer before investing.
7. Floor insulation for suspended timber floors
If you have ventilated timber floors:
- Insulating from below (where accessible) can cut heat loss.
- Typical cost ranges from £800–£2,000, but partial work may still help.
This measure is more disruptive, so it’s often best tackled alongside other works.
Step 4: Major upgrades that can leapfrog you to C (and beyond)
For some D-rated homes, particularly those already near the top of the band, one major upgrade may be enough to reach C or even B.
8. Air source heat pump (in well-insulated homes)
If your property is already well insulated, an air source heat pump can significantly improve both your EPC and carbon emissions.
- Strongest results in homes with good fabric efficiency and sized radiators.
- Often eligible for grants, such as the Boiler Upgrade Scheme.
See Air Source Heat Pump Costs UK and Boiler vs Heat Pump: Cost Comparison for costs and suitability.
9. Solar PV panels
Solar panels help by offsetting electricity use rather than reducing heat demand, but they still improve EPC scores.
- Typical cost: £4,000–£8,000+ depending on system size.
- Savings: Vary with usage patterns and export tariffs.
For a focused breakdown of EPC impact, see Solar Panels and EPC Rating.
10. Solid wall insulation (for older homes)
If you’re in a period property with solid walls, internal or external wall insulation can have a huge effect – but it’s a major project.
- Very effective for heat loss reduction and EPC scores.
- Expensive and potentially disruptive – often best combined with refurbishments.
For heritage-sensitive guidance, see How to Improve EPC on Victorian House.
How much will it cost to go from D to C?
Because every property is different, there’s no single price tag. But a common pattern for D → C is:
- £300–£600 for loft insulation top-up (if required)
- £800–£1,500 for cavity wall insulation (if available)
- Optional £200–£500 on controls/draught proofing
Total: Many homes can move from D to C for roughly £1,000–£2,000 if they’re starting from a reasonably efficient baseline.
If major systems (boiler, windows, walls) are outdated, costs may be higher – but so will the comfort and bill savings.
Grants and help for getting to band C
You may not have to fund everything yourself. Depending on your income, location and heating system, you may be eligible for:
- ECO4 and related schemes for insulation and heating upgrades
- The Boiler Upgrade Scheme for low-carbon heating
- Local authority grants for low-income or vulnerable households
We cover the landscape in Home Energy Grants UK 2025: Complete Guide to Funding (/insights/home-energy-grants-uk). Use this alongside our main cost guide, New Boiler Cost UK (2025 Guide), if a boiler upgrade is part of your D → C plan.
Landlords: D to C for rentals
If you’re a landlord, the D to C journey ties directly into compliance:
- Current minimum standard is generally band E (with exemptions).
- The government has proposed raising minimum standards towards band C for rentals.
Improving from D to C early can help you avoid a last-minute scramble later. For a full overview of the rules, exemptions and potential fines, see:
- EPC Rules for Landlords 2025–2030
- EPC Exemptions for Landlords Explained
- Landlord EPC Fines and Penalties
FAQs
What is the EPC score for band C?
Band C covers EPC SAP scores of 69–80. If your current rating is D 68, you may only need a small improvement; if you’re D 55, you’ll need more substantial upgrades.
What are the cheapest ways to move from D to C?
For many homes, the best value sequence is:
- Loft insulation top-up (if needed).
- Cavity wall insulation where available.
- Heating controls and draught proofing.
If you still fall short, consider a boiler upgrade or other larger works.
Do I need a new EPC after making improvements?
Yes. The EPC doesn’t automatically update. Once you’ve completed major upgrades, you’ll need to book a new assessment. Use Is My EPC Still Valid? to check whether you also need to replace an expiring certificate.
What should I do next?
- Use our EPC checker to confirm your current rating and recommendations.
- Make a shortlist of measures from this article and your EPC report.
- Read Cheapest Ways to Improve Your EPC Rating to order them by budget.
- Plan works over 6–24 months, starting with insulation and controls, then tackling heating and renewables as budget allows.
If you’re starting from band E rather than D, see How to Improve EPC from E to D for a more foundational roadmap.
If your property is EPC band E, you’re below the typical rating for much of the housing stock – and that’s increasingly a problem for energy bills, buyers and landlords.
The move from E to D is often a foundational upgrade step. It usually involves dealing with missing or very poor insulation and tackling obvious inefficiencies in your heating system.
This guide covers:
- Why moving from E to D matters
- Which improvements usually deliver the biggest gains
- How to plan upgrades in a realistic, budget-conscious way
For a full overview of improvement options, start with 27 Ways to Improve Your EPC Rating. Here, we focus on what specifically helps an E-rated property.
Why improving from E to D is important
- Energy bills: E-rated homes tend to be significantly more expensive to heat than D or C-rated homes.
- Comfort: You’re more likely to experience cold spots, draughts and condensation.
- Regulation (landlords): Current minimum standards are generally band E – but if your EPC expires and a new assessment drops you below E, you may struggle to let the property without improvements or exemptions.
Improving to D is often the first major milestone – and puts you in a stronger position to eventually reach C if desired.
Step 1: Understand your E rating
Start by grabbing your current EPC:
- Use our EPC checker to find your property by postcode.
- Note your current rating (e.g. E 43) and potential rating (e.g. C 73).
- Read through the recommended measures section.
Typical issues in E-rated homes include:
- Very little or no loft insulation
- Uninsulated cavity or solid walls
- Old electric storage heaters or non-condensing boilers
- Poor or non-existent heating controls
- Single glazed windows and significant draughts
We’ll tackle the most common improvement paths.
Step 2: Fix the worst heat loss first (insulation)
For most E-rated properties, insulation is the single most important factor.
1. Add or top up loft insulation
If your EPC mentions “Loft insulation (less than 100mm)” or similar, you’re likely losing a lot of heat through the roof.
- Aim for 270mm of insulation.
- Typical cost: £300–£600, less if you can do some or all of it yourself.
- Savings: £150–£250 per year depending on fuel type and property size.
This alone can sometimes move an E-rated home into D, especially when combined with smaller improvements. See Does Loft Insulation Improve Your EPC? for more detail.
2. Consider cavity wall insulation (if available)
If you have cavity walls and they’re currently uninsulated:
- Cavity wall insulation can deliver a large EPC jump, often +10–15 SAP points.
- Typical cost: £800–£1,500, but grants may be available.
Check your EPC or speak to an installer to confirm whether your walls are suitable. When combined with loft insulation, many E-rated homes can move to D or even C.
3. Draught proofing and basic fabric improvements
Once you’ve tackled the big gaps, deal with draughts:
- Seal around doors, windows and loft hatches using appropriate draught-proofing products.
- Consider secondary glazing or thicker curtains as interim measures where full window replacement isn’t yet affordable.
For a budget-first approach, see Cheapest Ways to Improve Your EPC Rating.
Step 3: Improve an inefficient heating system
If your EPC shows your heating system as a key weakness, upgrading it can make a large difference.
4. Replace very old gas boilers
If you have a non-condensing or very old gas boiler:
- Upgrading to an A-rated condensing boiler can improve efficiency and EPC scores.
- Combine the boiler upgrade with modern controls for best results.
We cover how much this can help in Does a New Boiler Improve Your EPC? and explain typical installation costs in New Boiler Cost UK (2025 Guide).
5. Improve electric heating (flats and some houses)
If you rely on old electric storage heaters or direct electric panel heaters:
- Consider high-heat-retention storage heaters or efficient electric systems with smart controls.
- In some cases, installing a heat pump may be viable and heavily supported by grants.
Because EPC calculations are sensitive to heating type and fuel, professional advice is essential before making big changes.
Step 4: Major measures (if needed)
If your property is at the bottom of band E (e.g. E 39) and has significant issues, you may need more structural changes such as:
- Solid wall insulation (internal or external) in older homes.
- Upgrading single glazing to double or secondary glazing.
- Installing an air source heat pump where the fabric is strong enough.
These are bigger investments and may be better suited to a long-term plan – especially if you’re ultimately aiming for band C. For period homes, see How to Improve EPC on Victorian House.
How much does it cost to go from E to D?
Costs vary widely, but a typical improvement path might involve:
- £300–£600: Loft insulation
- £800–£1,500: Cavity wall insulation (if suitable)
- £100–£300: Draught proofing and basic fabric improvements
- Optional £1,800–£3,000+: Boiler or heating system upgrade
Total investment to move from E to D is often in the £1,000–£3,000 range, depending on starting condition and property type.
Grants and schemes for E-rated homes
If your property is band E or lower, you may qualify for extra support:
- ECO4 and similar schemes target poorly rated homes, especially for lower-income households.
- The Boiler Upgrade Scheme can help fund heat pumps where appropriate.
- Local councils sometimes offer area-based insulation initiatives.
We summarise the key options in Home Energy Grants UK 2025: Complete Guide to Funding (/insights/home-energy-grants-uk). Check this alongside your EPC recommendations to see where grants might apply.
Landlords: staying on the right side of EPC rules
For landlords, E-rated properties are particularly important:
- Band E is generally the minimum required rating for most new tenancies and renewals (subject to exemptions).
- If a renewed assessment drops your property below E, you may not legally be able to let it without improvements or a valid exemption.
To understand your obligations and options:
- Read EPC Rules for Landlords 2025–2030.
- Check EPC Exemptions for Landlords Explained if improvements are not practical or would exceed cost caps.
- Review Landlord EPC Fines and Penalties to understand the risks of non-compliance.
FAQs
Is it worth improving from E to D if I can’t reach C yet?
Yes. Moving from E to D usually:
- Cuts bills significantly.
- Improves comfort and reduces damp/condensation risks.
- Puts you in a better position for future changes towards C when budget or grants allow.
What if my EPC is old – should I improve first or get a new one?
If your EPC is close to expiring anyway, it can be efficient to:
- Implement a couple of high-impact insulation improvements (e.g. loft/cavity wall).
- Then book a new assessment to capture your improved rating.
If you’re unsure whether your certificate is still valid, check Is My EPC Still Valid?.
What’s the best order to do improvements in?
For most E-rated homes, a sensible sequence is:
- Loft insulation (and cavity wall insulation if available).
- Draught proofing and basic fabric improvements.
- Heating system and controls upgrades.
- Larger measures like windows, solid wall insulation or heat pumps.
Use your property report from our EPC checker and our main guide, 27 Ways to Improve Your EPC Rating, to fine-tune this for your specific home.
Victorian homes are full of character – high ceilings, sash windows, ornate features – but they’re rarely energy efficient out of the box. Many sit in EPC bands E or D, and owners are often unsure how to improve them without compromising original details.
The good news: you can significantly improve a Victorian property’s EPC rating with the right mix of fabric upgrades, sensitive insulation and modern heating – while still respecting its period character.
This guide covers:
- Why Victorian homes perform poorly on EPCs
- Fabric-first measures that work with solid walls and sash windows
- Heating and renewable options that make sense for older properties
For a general overview of improvement options, see 27 Ways to Improve Your EPC Rating. Here, we’ll focus on period-home specifics.
Why Victorian houses often have low EPC ratings
Typical Victorian and late-19th-century homes share characteristics that EPC calculations penalise:
- Solid brick walls with no cavity to fill
- Single-glazed sash windows or early double glazing
- Little or no loft or floor insulation
- Older gas boilers or even electric heating in some conversions
- High ceilings and uncontrolled draughts
On your EPC, you’ll often see:
- “Solid brick walls – no insulation (assumed)”
- “Suspended timber floor – no insulation (assumed)”
- “Single glazed windows” or “Older double glazing”
Improving your rating means addressing these issues thoughtfully, balancing conservation with performance.
Step 1: Start with the least intrusive fabric upgrades
Before tackling walls and windows, focus on measures that have minimal visual impact but big thermal benefits.
1. Loft insulation (including eaves and access hatches)
Loft insulation is usually the lowest-risk, highest-return fabric upgrade:
- Aim for 270mm where headroom and ventilation allow.
- Pay attention to eaves areas, pipework and tanks to avoid freezing.
- Insulate and draught proof the loft hatch.
Victorian roofs can be irregular, so use installers experienced with older properties. For more detail, see Does Loft Insulation Improve Your EPC?.
2. Floor insulation for suspended timber floors
Many Victorian homes have suspended timber floors over a ventilated void.
- Insulating from below (e.g. from a cellar) is often the least intrusive option.
- Ensure ventilation is maintained to prevent damp and rot.
- Combine with draught proofing around skirting boards.
Even partial floor insulation in coldest rooms can cut draughts and improve EPC scores.
3. Draught proofing that respects period features
Victorian homes often leak heat through:
- Gaps around original doors and frames
- Traditional sash windows
- Unused chimneys and fireplaces
Look for heritage-sensitive solutions:
- Discreet brush seals for doors and sash windows.
- Chimney balloons or dampers in disused flues (while ensuring appropriate ventilation elsewhere).
- Heavy, well-fitted curtains and secondary glazing where replacement isn’t possible.
Much of this can be done without altering the building fabric permanently.
Step 2: Walls and windows – working with period constraints
Solid walls and original windows are the big challenge in Victorian properties.
4. Internal wall insulation (IWI)
Because Victorian homes usually have solid walls, you can’t simply inject cavity insulation. Instead, consider internal wall insulation:
- Often best applied to external-facing walls in key rooms.
- Use breathable systems designed for solid walls to reduce damp risks.
- Expect some loss of floor space and potential disruption to skirting, sockets and radiators.
Proper design and installation are critical. This is not usually a DIY job, and listed buildings need extra care and consent.
5. Secondary glazing for sash windows
Replacing original sash windows can be expensive and may not be allowed in conservation areas. Secondary glazing can be a good compromise:
- Adds an extra pane on the inside, improving thermal and acoustic performance.
- Often reversible, which can be important for heritage buildings.
- Can significantly reduce draughts and heat loss.
Some homeowners also choose sympathetic double-glazed sash replacements in less sensitive areas, using traditional sightlines and profiles.
6. External wall insulation (EWI) – in selective cases
External wall insulation can dramatically improve thermal performance but:
- Can change the appearance of the façade (rendering over brick).
- May be unacceptable in conservation areas or for listed buildings.
Where aesthetics and planning allow (e.g. less visible side/rear elevations), EWI can be combined with other measures for a major EPC uplift.
Step 3: Heating and hot water upgrades
Once the building fabric is significantly improved, focus on how you heat the home efficiently.
7. Upgrade an old boiler and controls
Many Victorian homes still run on aging non-condensing boilers.
- Replacing these with a modern A-rated condensing boiler can improve EPC ratings and reduce bills.
- Combine boiler replacement with zoned controls and thermostatic radiator valves.
For costs and EPC impact, see Does a New Boiler Improve Your EPC? and New Boiler Cost UK (2025 Guide).
8. Explore low-carbon heating (where suitable)
Heat pumps can work in Victorian homes, but only if:
- The property is well insulated, particularly at the loft and walls.
- Radiators or underfloor heating are sized for low-flow temperatures.
When the fabric is ready, an air source heat pump can significantly improve both EPC and carbon performance. See Air Source Heat Pump Costs UK and Boiler vs Heat Pump: Cost Comparison.
9. Hot water efficiency
Don’t overlook hot water:
- Fit or upgrade cylinder insulation and pipe lagging.
- Consider more efficient cylinders or controls where appropriate.
These measures are relatively inexpensive and support overall efficiency.
Step 4: Renewables and generation
Victorian homes can often accommodate renewables with careful design.
10. Solar PV and roof considerations
Solar panels can:
- Offset electricity use;
- Improve your EPC environmental rating;
- Reduce bills significantly if you’re home during the day.
Roof structure and aesthetics matter – especially in conservation areas – so use installers with heritage experience. We cover EPC impact in Solar Panels and EPC Rating.
11. Smart controls and zoning
For larger Victorian homes:
- Consider zoned heating (e.g. upstairs vs downstairs), smart TRVs, and room-by-room control.
- Use smart thermostats that learn occupancy patterns.
This is particularly helpful where parts of the home are only used occasionally.
Planning and phasing your Victorian retrofit
Improving a Victorian home’s EPC is rarely a one-weekend project. A sensible phasing could look like:
- Immediate comfort and fabric steps: loft insulation, draught proofing, basic floor insulation where accessible.
- Medium-term fabric upgrades: internal wall insulation in select rooms, secondary glazing.
- Heating upgrades: new boiler or heat pump (once fabric is improved), upgraded controls.
- Renewables: solar PV and other technologies where appropriate.
Use our EPC checker and property report to understand your current and potential ratings, and cross-reference suggestions with:
- 27 Ways to Improve Your EPC Rating
- Cheapest Ways to Improve Your EPC Rating
- How to Improve EPC from E to D and How to Improve EPC from D to C for band-specific paths.
Listed buildings and EPC exemptions
If your Victorian home is listed, some EPC recommendations may not be appropriate or permitted.
- Certain changes (e.g. external wall insulation, window replacement) may be restricted.
- In some cases, you may be able to register an EPC exemption where required works would unacceptably alter the character of the building.
For more on exemptions (particularly for landlords), see EPC Exemptions for Landlords Explained.
FAQs
Can I get a good EPC rating in a Victorian house?
Yes – with a well-planned retrofit, many Victorian homes can reach band C or better, especially when loft, floor and wall insulation are combined with efficient heating and controls. However, it may take more investment than for newer, cavity-walled properties.
What are the best first steps for a Victorian EPC upgrade?
In most cases:
- Loft insulation and basic draught proofing.
- Floor insulation where accessible.
- Secondary glazing or other window improvements.
From there, consider internal wall insulation and heating upgrades.
Do all EPC recommendations make sense for period homes?
No. Some generic recommendations (like certain types of external wall insulation or window replacement) may not be suitable for heritage properties. Always consider planning constraints, building physics and aesthetics – and speak to specialists where needed.
What should I do next?
- Use the EPC checker to see your current rating and recommendations.
- Make a fabric-first plan prioritising loft, floors and draughts.
- Combine this guide with 27 Ways to Improve Your EPC Rating to build a realistic 3–5 year upgrade roadmap.
With the right strategy, you can keep the character of your Victorian home and dramatically improve its comfort, running costs and EPC rating.
If your EPC mentions “Loft insulation (less than 100mm)” or “No loft insulation (assumed)”, you’re almost certainly losing more heat than you need to through the roof – and leaving EPC points on the table.
Loft insulation is one of the cheapest, most effective ways to improve your EPC rating, and it’s often the first upgrade energy assessors recommend.
This guide explains:
- How loft insulation affects your EPC score
- Typical costs and bill savings
- Whether it’s enough to move you up a band on its own
For a wider list of upgrade options, see 27 Ways to Improve Your EPC Rating. Here, we’ll focus purely on the roof.
How EPCs treat loft insulation
The EPC assessor records:
- Whether your property has a pitched roof and an accessible loft
- How much insulation is present (e.g. 50mm, 100mm, 270mm)
- Any known limitations (e.g. no access, sloping ceilings, flat roofs)
The calculation then estimates how much heat is lost through the roof. A well-insulated loft significantly reduces this, improving both:
- Your energy efficiency rating (the main A–G score)
- Your environmental impact rating (CO₂ emissions)
Properties with very little or no loft insulation are penalised heavily in the EPC model – which is why topping it up is such a common recommendation.
How much can loft insulation improve your EPC rating?
Exact EPC gains depend on:
- Your starting insulation level (e.g. 0mm → 270mm vs 100mm → 270mm)
- Property type and size (flat vs house, detached vs mid-terrace)
- Other factors like wall insulation and heating system
As a rough rule of thumb:
- Going from no insulation to 270mm can add 5–10 SAP points, sometimes more.
- Going from thin insulation (e.g. 50–100mm) to 270mm may add 3–6 SAP points.
For some properties, that can be enough to:
- Move from E to D or D to C when combined with other basic measures.
- Close a gap where you’re just 1–3 points short of the next band.
This is why loft insulation appears prominently in both How to Improve EPC from E to D and How to Improve EPC from D to C.
Typical costs and savings
Costs vary with insulation type, loft size and whether you DIY or hire a professional.
DIY loft insulation
- Materials (rolls of mineral wool or similar): often £200–£400 for an average 3-bed house.
- You’ll need safe access, suitable boards to walk on and care around wiring and fixtures.
DIY can be great for topping up existing insulation where the loft is easy to move around in and you’re confident with basic practical tasks.
Professional loft insulation
If access is tricky or you prefer not to DIY:
- Typical installation cost: £300–£700+ depending on loft complexity and location.
- Many installers also address ventilation, loft hatches and pipe/tank protection.
Annual savings
According to various UK energy-efficiency sources, typical savings for a gas-heated, semi-detached house can be around:
- £150–£250 per year when upgrading from no insulation to 270mm.
Exact figures will vary with energy prices and usage, but payback times are often quite short – especially if grants reduce your upfront cost.
Is loft insulation always the first upgrade?
In many homes, yes – but not always.
Loft insulation is often the first priority when:
- Your EPC explicitly warns of insufficient loft insulation.
- The loft is easily accessible and safe to work in.
- You haven’t done any other major fabric improvements yet.
Other measures may take priority when:
- You live in a top-floor flat with no individual loft space.
- The roof structure is unusual or already insulated in another way.
- You have very specific damp or condensation issues that need addressing first.
Use your property report from our EPC checker to see where loft insulation sits in your personalised list of recommendations.
Landlords: loft insulation and minimum standards
For landlords, loft insulation can be an essential part of meeting minimum EPC requirements:
- Poor roof insulation can drag a rental property into band F or G, risking non-compliance.
- Adding or improving loft insulation is usually low-disruption compared to other upgrades.
Improving roof insulation can make it easier to reach or maintain the required band, particularly if future changes raise the bar towards band C. For more on the rules, see:
How loft insulation works with other EPC improvements
Loft insulation is most effective when combined with:
- Wall insulation (cavity, internal or external, depending on property type)
- Floor insulation and targeted draught proofing
- Efficient heating systems and good controls
It makes sense to view it as part of a broader improvement plan:
- For budget-first ideas, see Cheapest Ways to Improve Your EPC Rating.
- For band-specific guidance, read How to Improve EPC from E to D and How to Improve EPC from D to C.
- For Victorian and solid-walled homes, see How to Improve EPC on Victorian House.
Grants and funding for loft insulation
Depending on your circumstances, you may not have to pay the full cost:
- National schemes such as ECO4 often fund or subsidise loft insulation for eligible households.
- Some local authorities run area-based schemes that include loft and cavity wall insulation.
We summarise the main options in Home Energy Grants UK 2025: Complete Guide to Funding (/insights/home-energy-grants-uk). Check this alongside your EPC recommendations to see whether you qualify.
FAQs
Is loft insulation enough to move me up an EPC band?
Sometimes. If you’re only a few SAP points short of the next band – and your loft is currently uninsulated or poorly insulated – topping up the loft can be enough. In many cases, though, you’ll need loft insulation plus one or two additional measures (like wall insulation or heating upgrades).
Do I need a new EPC after adding loft insulation?
Yes. The EPC is a snapshot at the time of assessment; it doesn’t auto-update. After completing loft insulation and any other significant improvements, you’ll need a new EPC assessment to capture your improved rating. See Is My EPC Still Valid? for validity rules.
Can loft insulation cause damp or condensation?
When done correctly with adequate ventilation, loft insulation should not cause damp problems – and may even help by keeping the house warmer. However, blocking essential airflow or insulating around existing moisture issues can create problems, so it’s important to:
- Maintain or improve roof ventilation.
- Avoid blocking air bricks or vents.
- Address known damp issues before adding large amounts of insulation.
What should I do next?
- Use the EPC checker to confirm what your current EPC says about your loft.
- Decide whether a DIY top-up or professional installation is right for you.
- Plan how loft insulation will fit into your wider upgrade strategy using 27 Ways to Improve Your EPC Rating.
As a relatively low-cost, high-impact measure, loft insulation is one of the best starting points for improving your EPC rating and cutting energy bills.
If your EPC recommends “Replace boiler with a new condensing boiler” or flags your heating system as inefficient, it’s natural to ask: will a new boiler actually improve my EPC rating – and by how much?
The short answer: yes, it often can, especially if you’re replacing a very old non-condensing boiler. But a new boiler is rarely the first step, and it works best when combined with insulation and better controls.
This guide covers:
- How EPCs treat boilers and heating systems
- How much EPC improvement you can realistically expect
- When a boiler upgrade makes sense vs when to prioritise other measures
For a full cost breakdown, read New Boiler Cost UK (2025 Guide). Here, we focus on EPC impact.
How EPCs assess your boiler and heating system
The EPC model looks at:
- The type of boiler (combi, system, regular)
- Whether it’s condensing or non-condensing
- The fuel it uses (mains gas, LPG, oil, etc.)
- The efficiency rating (often from manufacturer data or standard tables)
- The presence and quality of heating controls (thermostats, programmers, TRVs)
Together, these factors determine:
- How much energy is needed to heat your home to a standard level
- How much of that energy ends up as useful heat vs being lost in flue gases
Upgrading a boiler essentially improves the efficiency component – more of the energy you buy is turned into usable heat.
How much can a new boiler improve your EPC rating?
There is no one-size-fits-all answer, but typical patterns include:
- Replacing a non-condensing G-rated boiler with a modern A-rated condensing boiler can add several SAP points – sometimes enough to move a borderline property up a band.
- Upgrading from an already condensing but older boiler to a slightly more efficient model will have smaller EPC impact, though you may still see bill savings.
The biggest EPC gains generally occur when:
- Your current boiler is very old and inefficient.
- Your property already has reasonable insulation (loft/walls) so heating accounts for a large share of your energy use.
You can check how much your heating system is holding you back by reviewing the recommendations and heat demand sections on your EPC. Start by looking up your property via our EPC checker.
When is a new boiler worth considering for EPC improvement?
1. Your boiler is at end-of-life anyway
If your boiler is already:
- Breaking down frequently,
- Expensive to repair, or
- Nearing the end of its expected lifespan,
then upgrading to an efficient model gives you:
- Reduced running costs and improved reliability, and
- A better EPC rating as a side benefit.
2. You’re borderline on an EPC band
If you’re just a few points below a target band (for example, D 66 aiming for C 69):
- Loft/wall insulation and controls may close most of the gap.
- A boiler upgrade can then provide the extra push into the higher band.
Use How to Improve EPC from D to C and Cheapest Ways to Improve Your EPC Rating to decide whether a boiler or another fabric measure is the better “finisher” for your situation.
3. You’re a landlord planning ahead for tighter standards
For landlords, a new boiler can be part of a long-term strategy to reach or maintain minimum EPC standards:
- Current rules focus on avoiding F and G bands.
- Future proposals have pointed towards band C for rentals.
Upgrading to an efficient boiler can help protect you against future tightening of rules – but only if combined with fabric measures. For a full compliance view, see:
When other measures should come first
Even if your boiler is old, it isn’t always the first thing to change.
Priority often goes to:
- Loft insulation improvements – see Does Loft Insulation Improve Your EPC?
- Cavity wall insulation where suitable
- Basic draught proofing and floor insulation
- Heating controls (thermostats, programmers, TRVs)
These can be cheaper per EPC point gained than a boiler replacement. Once you’ve addressed them, a boiler upgrade can then maximise the benefit of your reduced heat demand.
Boiler types and EPC impact
Gas combi vs system vs regular boilers
From an EPC perspective:
- What matters most is the efficiency rating, not just the boiler type.
- A modern A-rated combi or system boiler will generally score better than an old G-rated boiler of any type.
Other considerations (hot water comfort, cylinder vs combi, system complexity) should also inform your choice but are not directly EPC-specific.
Electric boilers and direct electric heating
Electric boilers can simplify pipework, but in the EPC model, electric resistance heating is treated as less efficient from a primary energy and carbon perspective than gas – even if the device itself is “100% efficient” at point of use.
That means switching a gas boiler to a straightforward electric boiler can hurt your EPC unless you pair it with exceptionally good insulation or on-site generation (like solar PV).
Heat pumps vs boilers
Heat pumps are treated very favourably in EPC calculations because they deliver multiple units of heat for each unit of electricity consumed.
- In some homes, switching from a gas boiler to a well-designed heat pump can significantly boost EPC scores.
- However, they work best in well-insulated properties with suitable emitters (radiators/underfloor).
For a detailed comparison of running costs and suitability, see Boiler vs Heat Pump: Cost Comparison and Air Source Heat Pump Costs UK.
How much does a new boiler cost?
Costs depend on:
- Property size and heat requirement
- Boiler type and brand
- Installation complexity (e.g. relocating boiler, flue changes, system cleaning)
Our full breakdown is in New Boiler Cost UK (2025 Guide), but as a broad range:
- Combi boiler replacement: often £2,000–£3,000+ including installation
- System or regular boiler upgrades: often £2,500–£4,000+ depending on cylinder and system changes
Because these are ballpark figures, always get fixed quotes from reputable installers before making a decision.
Grants and funding for boiler upgrades
Grants for traditional gas boilers are more limited than for low-carbon options, but you may still benefit from:
- Boiler upgrade or replacement schemes targeting inefficiency (through some local programmes).
- Wider home energy grants that include heating upgrades as part of a package.
If you’re more interested in switching to a heat pump, the Boiler Upgrade Scheme may help with upfront costs. For an overview of the funding landscape, see Home Energy Grants UK 2025: Complete Guide to Funding (/insights/home-energy-grants-uk) and Boiler Grants UK 2025.
How a new boiler fits into your overall EPC plan
Think of a new boiler as one element in a wider improvement strategy:
- If you’re going from E to D, focus first on loft and wall insulation, then consider the boiler – see How to Improve EPC from E to D.
- If you’re going from D to C, the boiler may be a key part of the final push, especially in homes already well insulated – see How to Improve EPC from D to C.
- For Victorian or solid-walled homes, make sure the fabric is addressed before sizing new heating – see How to Improve EPC on Victorian House.
Use your property report from our EPC checker to see where “replace boiler” sits in the list of recommended measures and compare it against cheaper EPC wins.
FAQs
Will a new boiler on its own move me up an EPC band?
Sometimes – especially if your current boiler is very old and you’re close to the next band. But in many cases, you’ll need boiler + insulation or boiler + controls to see a full-band improvement.
Do I need to change radiators when I replace my boiler?
Not always. Many boiler replacements can reuse existing radiators, though your installer may recommend system cleaning or partial radiator upgrades for best performance. Heat pumps, by contrast, more often require emitter changes due to lower flow temperatures.
Should I pick a boiler or a heat pump for a better EPC?
From an EPC perspective, a well-designed heat pump can often score better than a gas boiler – but only if your property is ready and the system is correctly specified. A high-efficiency boiler may still be the more practical step in many homes today. Compare both using Boiler vs Heat Pump: Cost Comparison and your EPC recommendations.
What should I do next?
- Use the EPC checker to view your current rating and recommendations.
- Read New Boiler Cost UK (2025 Guide) for pricing context.
- Consider whether loft/wall insulation and controls should come before or alongside a boiler upgrade.
- Once you’ve made improvements, book a new EPC assessment to see your updated rating – and then plan the next steps using 27 Ways to Improve Your EPC Rating.