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External wall insulation is a method of improving energy efficiency in buildings by applying a layer of insulation to the exterior walls. This can be done using a variety of materials, including polystyrene, mineral wool, and wood fibre. External wall insulation can significantly reduce heating bills and improve indoor comfort. However, the cost of external wall insulation can vary depending on several factors, including the size of the building, the type of insulation used, and the complexity of the installation.
Unlike the external wall, cavity wall insulation is a process of using insulating material to fill the void between the outer and inner walls. This is usually more prevalent for structures that were constructed after the 1920s because they contain a cavity wall structure. This means you will be able to keep out the cold by filling this gap with insulating material. Mineral wool, polystyrene beads, and polyurethane foam are some of the more frequently used materials to insulate cavity wall insulation. Cavity wall insulation is cheaper than external wall insulation and can help you cut down on your energy costs considerably. The method is useful to boost the energy efficiency of your home.
External & Cavity Wall Insulation Cost in 2024
In 2024, the cost of external wall insulation can vary significantly based on several important factors. These factors include your home size, insulation material type, and the difficulty involved in the installation process. You can generally expect to pay between £6,000 and £15,000 for a detached house. However, smaller properties might cost less, while larger homes could be more expensive. It is essential to get quotes from multiple installers to get an accurate estimate.
On the other hand, the cavity wall insulation cost in 2024 is generally more affordable than external wall insulation. Homeowners can expect to pay between £500 and £2,500, depending on the size of the property and the type of insulation material. For a standard semi-detached house, the cost is usually around £800 to £1,200. If you are a low-income household and can’t afford that lump sum, you can get Government grants. The UK government offers different free insulation programmes to help low-income households just like you. With these programmes, you don’t need to pay a single penny from your pocket. This initiative is absolutely free of cost.
Costs of External Wall Insulation
- Average Spending: £100 to £250 per square metre covering.
- Total cost of external wall insulation: It usually falls between £7,000 and £15,000.
- Installation cost: External wall insulation on a three-bedroom semi-detached home is about £10,000.
Break Down of Material Costs for External Wall Insulation
- Expanded Polystyrene (EPS): Typically ranges from £120 to £150 per square metre.
- Mineral Wool: Tends to be a bit pricier at £140 to £160 per square metre.
- Wood Fibre: it’s a much cheaper option at around £19 per square metre.
Keep in mind that these are approximate averages, and the actual costs may vary based on your specific requirements.
Cavity Wall Insulation Cost
- Average Spending: cost of cavity wall insulation per m2 can range from £13 – £30 considering insulation material alone.
- Installation cost: Cavity wall insulation installation cost ranges from £1,000 to £4,600, based on the type and size of property.
Break Down of Material Costs for Cavity Wall Insulation
- Mineral Fibre: Typically ranges from £13 to £18 per square metre.
- Glass Wool: Ranges from £13 to £18 per square metre.
- Wool Fibre: £25 to £30 per square metre.
- Cavity Wall Boards: £15 to £17 per square metre.
- Expanded polystyrene beads: £18 to £22 per square metre.
- Polyurethane foam: £22 to £26 per square metre.
Keep in mind that these are approximate averages, and the actual costs may vary based on your specific requirements.
Potential Savings on Energy Bills
Both external and the cavity wall insulation therefore results in a big saving on your energy bills. How much one stands to save varies with several considerations. These include the size of the house, the insulation type to be installed, and the current EPC rating.
For instance, external wall insulation can save you £455 per year on heating bills for an average detached house. Likewise, approximately £285 per year can be saved on cavity wall insulation for a semi-detached house.
Factors Affecting Insulation Costs
There are some factors that can influence the price of external and cavity wall insulation. One of the most important is the size of the house. The bigger the house, the more materials will be needed to insulate the house. Insulation material costs vary depending on the material types. So it would be another factor that will affect the overall costs.
For example, high-performance insulation materials such as polyurethane foam cost more than ordinary upward-forward insulation material like mineral wool. Also, the complexity of the installation may determine the costs required to have the system put in place. Firms with complex designs, asymmetrically shaped, more than one storey or other complicated structural designs will attract a higher cost.
Advantages of External and Cavity Wall Insulation
Investing in wall insulation offers several benefits beyond just cost savings on energy bills. Firstly, insulation can improve the comfort of your home by maintaining a more consistent indoor temperature. This can make your home feel warmer in the winter and cooler in the summer. Insulation can also help to reduce noise from outside, providing a quieter and more peaceful living environment. Furthermore, insulating your walls can increase the value of your property by improving its energy efficiency rating. Homes with higher energy efficiency ratings are more attractive to potential buyers.
How to Choose the Right Insulation for Your Home
Choosing the right insulation for your home depends on several factors. These include the age and type of your property, your budget, and your energy-saving goals. For older homes with solid walls, external wall insulation may be the best option to maximise energy savings. For properties with cavity walls, cavity wall insulation is usually a more cost-effective solution. It’s essential to consider the long-term benefits and savings when deciding on the type of insulation. Consulting with a professional insulation installer can provide valuable insights into the best options for your home. They can conduct a thorough assessment of your property and recommend the most suitable insulation type and material.
Government Grants and Funding for Insulation
In the UK, several government grants and funding schemes can help reduce the cost of wall insulation. These schemes aim to improve energy efficiency in homes, reduce carbon emissions, and help homeowners save on energy bills. The Energy Company Obligation (ECO) scheme, for example, provides funding for insulation and other energy efficiency improvements for eligible households. Taking advantage of these schemes can significantly reduce the upfront cost of insulation, making it a more affordable investment.
1. Energy Company Obligation (ECO4) Scheme (Active)
The ECO4 scheme requires energy suppliers to help low-income households and vulnerable groups improve their energy efficiency. One way they do this is by offering grants towards the cost of external and cavity wall insulation. To be eligible for ECO4 funding, you must meet certain criteria. This criterion includes having a low income or being in receipt of certain benefits. The specific requirements can vary depending on your local circumstances.
2. Green Homes Grant Scheme (Closed)
The Green Homes Grant scheme provided funding for homeowners to improve the energy efficiency of their homes. One of the eligible improvements was external and cavity wall insulation. The scheme was open to homeowners who met certain eligibility criteria. This criterion consists of having a property with an Energy Performance Certificate (EPC) rating of D or below. Unfortunately, the Green Homes Grant scheme has now closed. It may be worth checking with your local council to see if any similar schemes are available.
3. Great British Insulation Scheme (Active)
The Great British Insulation Scheme aims to help homeowners reduce their energy bills by improving the insulation. The scheme offers funding towards the cost of external and cavity wall insulation. To be eligible for the GBIS, you must have a property with a low EPC rating. The specific requirements can vary depending on your local circumstances.
The Installation Process for Wall Insulation
The installation process for both external and cavity wall insulation involves several steps. The first step is to prepare the exterior walls by cleaning them and making any necessary repairs. Insulation boards are then fixed to the walls, followed by a protective layer of render or cladding. The entire process can take several days to complete, depending on the size of your property. For cavity wall insulation, the process is quicker and less disruptive. Small holes are drilled into the exterior walls, and insulation material is blown into the cavity using specialised equipment. Once the cavity is filled, the holes are sealed, and the process is complete. Both types of insulation require professional installation to ensure they are effective and safe.
Maintenance and Longevity of Wall Insulation
Both external and cavity wall insulation are designed to last for many years with minimal maintenance. However, it’s essential to check the condition of your insulation regularly to ensure it remains effective. For external wall insulation, this involves inspecting the render or cladding for cracks and repairing them. Cavity wall insulation requires less maintenance, but it’s still a good idea to have it checked periodically. Properly installed and maintained insulation can last for decades, providing on-going savings and comfort.
Common Myths About Wall Insulation
There are several common myths about wall insulation that can deter homeowners from making this beneficial investment. One of the most prevalent myths is that insulation can cause damp problems. In reality, properly installed insulation helps prevent dampness by reducing condensation within the walls. Another myth is that insulation is only beneficial in colder climates. Insulation is useful for retaining heat in winter and helps keep homes cooler in the summer. Some homeowners may also believe that insulation is too expensive. However, considering the long-term savings on energy bills and potential government grants, insulation is often more affordable than people think.
Summary
Investing in wall insulation is a smart decision for any homeowner looking to reduce energy bills. Understanding the insulation cost can help you make informed decisions that suit your budget. Whether you choose external or cavity wall insulation, the benefits of a warmer, more energy-efficient home makes it a worthy investment.
Frequently Asked Questions
The costs of External Wall Insulation (EWI) and Cavity Wall Insulation (CWI) can vary based on factors such as the size of your home, the type of insulation materials used, and the complexity of the installation process.
Generally, External Wall Insulation tends to be more expensive than Cavity Wall Insulation due to the additional labour and materials involved in the external application. However, the specific costs can vary depending on individual circumstances.
In many regions, government grants or subsidies are available to help homeowners offset the cost of insulation. It’s advisable to check with your local authorities or energy efficiency agencies to see if you qualify for any financial assistance.
