Why is External Wall Insulation Popular?
External wall insulation (EWI) has become increasingly popular due to its numerous benefits. One of the main benefits of external wall insulation is that it helps to improve the thermal performance of a building, which in turn reduces energy consumption and lowers energy bills.
EWI systems are built up in several layers, which include insulation board, render, reinforcement mesh, primer, and a decorative finish or top coat render. Homeowners can even choose a brick-effect finish to maintain the traditional character of their property.
Another reason for the popularity of EWI is that all the work takes place outside, which means that there is no need to move out during the renovation work. Unlike internal wall insulation, which can reduce the inside space by up to 7%, choosing EWI avoids interfering with plumbing and electrics and does not impact the space inside the home.
Benefits of External Wall Insulation
1. Improve Thermal Comfort
External wall insulation (EWI) can improve thermal comfort in a property by ensuring that the inside of the property is kept at a comfortable temperature throughout all weather conditions. This means that the property will be warm in the winter and cool in the summer, providing a comfortable living environment for occupants.
By limiting heat loss, EWI improves the indoor thermal comfort, reduces heating costs, and limits CO₂ pollution.
2. Cooler Summers, Warmer Winters
Insulation is crucial for maintaining thermal comfort in a house. External Wall Insulation (EWI) provides year-round benefits by keeping the house warm in winter and cool in summer. EWI ensures that heat generated by the central heating system is retained within the building, while also preventing cold air from entering the property.
During summer, the walls do not absorb heat radiated by the sun, which helps maintain a cool indoor temperature. Wood Fibre insulation is a high-performance material that is particularly effective in keeping the house cool during summer. EWI is an excellent investment for homeowners who want to enjoy a comfortable living space all year round.
3. Reduce Energy Bills
By installing external wall insulation, homeowners can significantly reduce their energy bills. For example, a four-bedroom detached house can save up to £455 per year on energy bills by installing 90mm of EPS onto a solid brick wall. This investment pays for itself over time and provides long-term savings.
4. Improve External Aesthetics
External Wall Insulation (EWI) not only improves the thermal performance of a building but also enhances its external aesthetics. EWI Pro renders are highly functional and watertight, available in a wide range of colours and textures. This allows for a unique and customisable finish that will stand the test of time. The render finish ensures the EWI system is not only practical but also aesthetically appealing.
5. Save Floor Space
External Wall Insulation (EWI) has the advantage of not taking up any internal floor space. This is because the insulation is attached to the external walls with adhesive and mechanical fixings, leaving the entire interior space unaffected.
For those living in properties where space is at a premium, this is a significant benefit. Additionally, the installation process is quick and unintrusive, making it a hassle-free option for homeowners. To ensure a quality installation, it is recommended to find an approved installer with EWI Pro.
6. Reduce Carbon Footprint
External wall insulation can significantly reduce a household’s carbon footprint. By reducing the need for gas and electric heating throughout the year, households with EWI contribute to helping the environment.
7. Increase Lifespan of Building Fabric
External wall insulation can help to increase the lifespan of a building’s fabric. By encasing the entire exterior of a property in a thermal blanket, it reduces heat loss and protects against weathering. The external render that finishes the system acts as a weather-proof barrier, preventing water ingress and damage from extreme weather conditions. This means that the building fabric is protected at all times, which can prolong the life of the building.
8. Acoustic Insulation and Fire Resistance
EWI Pro Mineral Wool systems utilize Rockwool as the insulating material. This material is well-known for its excellent acoustic insulating capabilities and fire resistance, making EWI Pro Mineral Wool systems a premium choice for users. The system offers a wide range of unique benefits, making it an excellent choice for those seeking high-quality insulation.
9. Minimise Thermal Bridging
Thermal bridging is when heat loss is concentrated in gaps within an insulation system, leading to the accumulation of water and condensation. This can significantly reduce the effectiveness of insulation. However, with External Wall Insulation (EWI), thermal bridging is minimised due to the seamless nature of the system. EWI is applied externally and does not require breaks within the insulation boards, thus reducing the risk of thermal bridging.
10. Reduce Damp and Condensation
External Wall Insulation (EWI) can help reduce the occurrence of damp and condensation in buildings. This is because insulation slows down heat transfer, which means that the walls stay warmer. As a result, when hot air comes into contact with the walls, condensation is vastly reduced. This helps to improve indoor air quality and maintain the structural integrity of the building.
To ensure a successful EWI installation, it is recommended to seek detailed design and specification advice from a technical team. On-site support and training are also available to ensure that the installation is done correctly. Additionally, the EWI System Calculator can provide guidance on required materials.
Frequently Asked Questions
What are the benefits of external wall insulation?
External wall insulation provides numerous benefits, including reduced heat loss, lower energy bills, and increased comfort. It also allows walls to contribute to thermal mass, which can lead to a “tea cosy” effect. Additionally, external wall insulation can help to reduce CO2 pollution and improve the thermal performance of a building.
How does external wall insulation impact energy efficiency?
External wall insulation can significantly improve a building’s energy efficiency by reducing heat loss through the walls. This, in turn, can lead to lower energy bills and a more comfortable living environment. By improving the thermal performance of a building, external wall insulation can also help to reduce CO2 pollution and contribute to a more sustainable future.
What is the expected lifespan of external wall insulation?
The expected lifespan of external wall insulation can vary depending on a number of factors, including the quality of the insulation materials, the installation process, and the level of maintenance. However, with proper installation and maintenance, external wall insulation can last for several decades.
What are the cost savings associated with external wall insulation?
External wall insulation can provide significant cost savings over time by reducing energy bills and improving the overall energy efficiency of a building. While the initial cost of installation may be higher than other insulation methods, the long-term savings can more than make up for this initial investment.
Is external wall insulation suitable for all types of walls?
External wall insulation can be suitable for a wide range of wall types, including brick, concrete, and timber. However, it is important to consult with a professional installer to ensure that the insulation is compatible with the specific wall type and that the installation process is carried out correctly.
How does external wall insulation impact the appearance of a building?
External wall insulation can be designed to match the existing appearance of a building, or it can be used to create a new look. This can include a range of finishes, such as render, cladding, and brick slips. By improving the appearance of a building, external wall insulation can also increase its value and curb appeal.