For most homes, the answer is yes—especially when considering long-term energy savings, increased comfort, and sustainability benefits.
However, the decision depends on factors such as installation costs, the specific type of property, and the amount of disruption you’re willing to tolerate.
With rising energy costs and growing concerns about sustainability, more homeowners are turning to External Wall Insulation Installers to reduce heating bills and enhance the overall comfort of their homes.
In this article, we’ll explore the financial, environmental, and comfort-related benefits of EWI, while also addressing the potential downsides to help you make an informed decision.
Key Benefits of EWI
Energy Efficiency
One of the biggest advantages of external wall insulation is its ability to drastically reduce heat loss. It works by providing a continuous insulating layer on the outside of your home, helping keep the warmth in during winter and cool air inside during summer.
EWI can prevent up to 35% of heat loss from the walls of your home, compared to other forms of insulation like cavity wall insulation or internal wall insulation, which tend to be less effective at creating a complete thermal barrier.
In comparison to cavity wall insulation, which only insulates the internal gap between two walls, EWI covers the entire external surface of the building.
This comprehensive approach results in more consistent and efficient temperature regulation, particularly for older properties with solid or non-cavity walls.
Financial Savings
The installation of EWI can lead to significant reductions in your heating bills. For an average UK household, EWI can save around £300 to £500 per year in energy costs, depending on factors such as house size, insulation thickness, and the material used.
While the upfront cost of installation can range from £5,000 to £15,000, the payback period typically ranges from 20 to 30 years. The exact payback period depends on your energy usage and the specific materials used. However, the long-term savings on energy bills generally outweigh the initial investment, making it a cost-effective solution over time.
Increased Home Comfort
EWI doesn’t just save you money; it also increases the comfort of your home. Insulating the outside of your home helps maintain a stable indoor temperature, reducing the likelihood of cold spots or drafts. This leads to a more comfortable living environment, especially in older properties that may have suffered from poor insulation or significant heat loss.
In addition, EWI helps manage moisture levels within your home, reducing the risk of dampness and condensation. This can help prevent common issues like mold growth, which is often exacerbated by cold walls and inadequate insulation.
Resale Value & EPC Rating
Homes with high-quality insulation, including external wall insulation, typically perform better in terms of resale value. The increased energy efficiency and enhanced comfort can make a home more attractive to potential buyers. Additionally, EWI can significantly improve a property’s Energy Performance Certificate (EPC) rating, which is increasingly becoming a key factor in the buying decision.
With better energy efficiency, homes with EWI are often seen as more cost-effective and environmentally friendly, giving them an edge in the property market.
Sustainability & Carbon Savings
External wall insulation plays an essential role in reducing your home’s carbon footprint. By improving energy efficiency, EWI helps reduce the amount of energy needed to heat your home, which directly reduces carbon emissions. Over its lifespan, EWI can save around 1,000 to 1,500kg of CO2 per year, contributing to the UK’s goal of achieving Net Zero emissions by 2050.
This makes EWI not only a smart choice for homeowners but also a positive step toward more sustainable living.
Potential Downsides
High Upfront Cost
One of the primary concerns for homeowners considering EWI is the high upfront cost.
But how much does EWI cost in the UK? As mentioned, the installation of EWI can range from £5,000 to £15,000, depending on factors such as the size of the property, the materials used, and any additional work required (e.g., rendering or cladding).
However, financing options such as loans or grants may be available to help offset the cost. Government schemes, such as the ECO4 (Energy Company Obligation), can also assist low-income households in covering part or all of the cost.
Aesthetic Changes & Planning Permission
Another consideration is that EWI can alter the appearance of your home. Some homeowners are concerned that the installation of EWI might change the look of their property. Additionally, in some cases, planning permission may be required, especially if your property is listed or in a conservation area. It’s essential to check with your local council before proceeding with installation.
Installation Challenges
The installation of external wall insulation can be a complex and time-consuming process. It typically takes 1-3 weeks for a team of professionals to complete the installation of EWI on an average-sized house. During this period, you may experience some disruption to daily life, as scaffolding will need to be erected, and the installation team will need access to various parts of your home’s exterior.
Potential Damp Risks
If not properly installed, external wall insulation can lead to issues like condensation and interstitial damp. This typically occurs when there is insufficient ventilation behind the insulation or if moisture gets trapped during installation. To avoid these problems, it’s crucial to hire experienced professionals who follow the correct procedures and ensure proper ventilation behind the insulation layer.
Real-World Data: Cost vs. Savings
Let’s break down the estimated costs and savings to help you better understand the return on investment for external wall insulation.
| House Type | EWI Cost | Annual Energy Savings | Payback Period |
|---|---|---|---|
| Semi-Detached | £10,000 | £300-£500 | 20-25 years |
| Detached | £15,000 | £400-£600 | 25-30 years |
| Mid-Terrace | £8,000 | £250-£450 | 20 years |
As shown in the table, the payback period for EWI installation can vary, but it typically takes 20-30 years for homeowners to fully recover the cost through energy savings.
Despite the long payback period, the continued savings on heating bills and the improved comfort levels make it a worthwhile investment in the long run.
Grants & Financial Support
There are several grants and funding options available to help reduce the upfront cost of installing external wall insulation. So, what grants are available for EWI?
| Scheme | Funding Type | Who Qualifies |
|---|---|---|
| ECO4 | Partial/Full Grant | Low-income households |
| Great British Insulation Scheme | Partial Grant | Homes with low EPC ratings |
These schemes are designed to assist low-income households or those living in homes with poor EPC ratings. Depending on eligibility, grants can cover part or even all of the installation cost.
Final Verdict: Is EWI Worth It?
In conclusion, external wall insulation is worth the investment for many homeowners, especially those living in older homes with solid or non-cavity walls. The benefits—reduced heating bills, improved home comfort, increased property value, and sustainability—generally outweigh the high upfront cost.
If you’re looking for long-term savings, energy efficiency, and a more comfortable living environment, EWI is a smart choice. Additionally, government grants can make it more affordable, so it’s worth checking if you qualify for financial support.
FAQ’s
Does EWI increase home value?
Yes, homes with external wall insulation typically have higher energy efficiency, which can increase their resale value.
Is EWI better than cavity wall insulation?
EWI is more effective than cavity wall insulation for homes without cavities or those with solid walls. It provides more comprehensive thermal coverage.
How long does external wall insulation last?
EWI generally lasts between 30 to 40 years, depending on the materials used.
Can I get EWI for free?
Low-income households and homes with poor EPC ratings may be eligible for government grants that cover part or all of the EWI installation cost.
