Retrofitting homes across the UK is a rising priority, especially with nearly half (48%) of all properties rated EPC D or below, as JLL’s research shows. Improving these ratings is essential to meet sustainability goals, lower tenant bills, and boost property values. Retrofitting – upgrading a building’s energy efficiency without a full rebuild – is often a practical solution for housing providers and landlords. But what exactly is retrofitting, and what are the retrofitting costs involved?
What is Retrofitting?
Retrofitting involves updating existing buildings with energy-efficient technologies and materials to reduce energy consumption and carbon emissions. This process can include structural improvements like insulation or modern technology such as heat pumps. For housing providers, retrofitting offers a strategic way to improve property quality while aligning with environmental and regulatory standards, such as potential upcoming changes to EPC requirements. These upgrades help properties achieve a minimum EPC rating of C or higher, a target that may soon become a requirement for rental units.
Examples of Retrofitting Costs
Costs for retrofitting can vary widely depending on the type of upgrade, property size, and location. Here’s a breakdown of some common retrofitting methods and their costs, drawing on data from GOV.UK and Rightmove.
1. Insulation
- Cavity Wall Insulation: Costs range from £480 to £1,400 depending on wall conditions. Cavity wall insulation is one of the most cost-effective ways to enhance a property’s thermal efficiency.
- Internal Wall Insulation: Prices range from £6,800 to £8,900 per property, with per-meter costs varying from £55 to £140. This option is ideal for properties with limited exterior space or aesthetic restrictions.
- External Wall Insulation: Ranging from £7,100 to £15,000, this type of insulation can be pricier but significantly improves thermal efficiency and reduces external noise.
- Loft Insulation: For around £185 to £670 (up to £2,000 for hard-to-treat cases), loft insulation can dramatically reduce heat loss in homes with attic spaces.
- Underfloor Insulation: Typically costing £3,500 to £8,300, this insulation is beneficial for properties with accessible floor voids.
2. Glazing
- Double Glazing Replacement: Costs vary, with full replacements (panes and frames) ranging from £3,900 to £10,700 per property. Double glazing is essential for reducing heat loss and improving indoor comfort, especially in colder climates.
3. Heating System Upgrades
- Gas Boiler Replacement: Replacing a gas boiler can cost between £1,600 and £2,400, with newer, A-rated boilers saving tenants up to £580 per year on heating.
- Heat Pumps: Air-source heat pumps are a pricier option, around £14,000, but they can save approximately £340 annually. This system is also eligible for certain government grants, offsetting initial costs.
- Heating Controls: Installing new controls costs around £450, allowing for better temperature management, improving energy efficiency, and potentially lowering utility bills.
4. Additional Measures
- Solar Panels: Installation costs approximately £7,000, with annual savings of up to £545 depending on location and sunlight exposure. Solar panels can also increase a property’s value by £1,350 to £5,400.
- Draught-Proofing: A more affordable retrofit option, draught-proofing costs between £85 and £275, helping prevent heat loss and enhance occupant comfort.
- LED Lighting: Switching to energy-efficient LED lighting can cost between £4.20 and £9.80 per bulb, providing substantial long-term savings on electricity.
With these measures combined, the average retrofit cost per home can total around £35,000 according to Green Alliance, but the expenses may vary. Retrofits can also lead to an increase in property value, with some reports showing an average boost of £10,000 when energy-efficient systems are installed.
| Retrofit Measure | Cost Range | Description |
| Insulation | ||
| Cavity Wall Insulation | £480 – £1,400 | Cost-effective for enhancing thermal efficiency, based on wall conditions. |
| Internal Wall Insulation | £6,800 – £8,900 | Ideal for properties with limited exterior space; £55 – £140 per meter. |
| External Wall Insulation | £7,100 – £15,000 | More expensive but greatly improves thermal efficiency and reduces noise. |
| Loft Insulation | £185 – £670 | Effective for reducing heat loss; up to £2,000 for hard-to-treat lofts. |
| Underfloor Insulation | £3,500 – £8,300 | Beneficial for homes with accessible floor voids. |
| Glazing | ||
| Double Glazing Replacement | £3,900 – £10,700 | Essential for reducing heat loss and improving comfort, especially in colder climates. |
| Heating System Upgrades | ||
| Gas Boiler Replacement | £1,600 – £2,400 | Newer A-rated boilers can save up to £580 per year on heating costs. |
| Heat Pumps (Air Source) | Around £14,000 | Price option with approx. £340 in annual savings; eligible for government grants to offset costs. |
| Heating Controls | Around £450 | Improves temperature management, boosts energy efficiency, and lowers bills. |
| Additional Measures | ||
| Solar Panels | Around £7,000 | Annual savings of up to £545; increases property value by £1,350 – £5,400. |
| Draught-Proofing | £85 – £275 | Affordable option to prevent heat loss and enhance comfort. |
| LED Lighting | £4.20 – £9.80 per bulb | Energy-efficient lighting offers long-term electricity savings. |
Why Should You Retrofit Your Home?
1. Lower Bills: Retrofitting directly reduces energy consumption, lowering bills for tenants and mitigating financial pressures from energy price hikes. Housing providers also benefit by offering a more attractive, affordable rental experience.
2. Environmentally Friendly: Energy-efficient properties conserve resources, reducing carbon footprints. Retrofitting aligns with the UK’s sustainability goals and the global drive to combat climate change.
3. Future Proofing Properties: EPC standards may continue to evolve, pushing more properties toward minimum ratings. Retrofitting today prepares properties for tomorrow’s requirements, protecting long-term asset value.
4. Boost Property Value: By modernising energy efficiency, retrofits can enhance a home’s value. For example, moving an EPC rating from F to C could increase a property’s value by up to 15%, according to Rightmove.
How to Retrofit Your Home: Four Key Steps
Completing a successful retrofit involves a few essential steps, which can be adjusted based on the property and goals. Here’s a simple guide for housing providers:
1. Assess Energy Efficiency: Begin by understanding the energy performance of each property. Energy Performance Certificates (EPCs) give a clear view of a building’s energy status, identifying areas for improvement. Alternatively, a detailed home energy plan or assessment by a professional can provide tailored recommendations.
2. Conduct a Home Survey: A professional surveyor will assess specific needs, tailoring the retrofit plan to the property’s unique features. This can involve checking insulation levels, assessing heating systems, and identifying areas prone to energy loss, humidity, or mould. A post-retrofit EPC will also help verify the effectiveness of improvements.
3. Find Qualified Contractors: Skilled contractors are essential for effective retrofitting. For insulation, glazing, or heating systems, seek certified experts who understand the complexities of energy efficiency. Trustmark and other industry organisations can help connect you with qualified professionals.
4. Explore Financing Options: Financing can be a significant concern, but various funding options and grants exist. The UK government and local councils may offer support, especially for energy-saving improvements like insulation and heating upgrades. It’s also possible to phase out upgrades over time, prioritizing essential tasks as recommended by your energy assessor.
Prove the Value of Your Retrofit with ResiSure
Retrofitting brings a host of benefits to housing providers and tenants alike, from reducing energy costs and emissions to enhancing property value and meeting evolving regulations. But proving the effectiveness of retrofits is essential, especially when it comes to applying for grants or demonstrating compliance with EPC standards.
ResiSure’s technology provides a unique solution by giving real-time insights into key environmental metrics like temperature, humidity, and mould levels across your property portfolio. Our smart, wireless devices take readings every half hour, ensuring you have an accurate, up-to-date picture of each home’s living environment. This data is displayed on your customisable dashboard and sent via regular reports, helping you understand trends and prevent issues before they arise.With ResiSure, housing providers gain a powerful tool to not only improve tenant living conditions but also validate the impact of their retrofit activities, supporting future retrofit projects and funding opportunities. To find out more about our groundbreaking tech, get in touch with our team below – we’d love to help you validate your retrofit and future-proof your properties for years to come.