External Wall Insulation Systems

Our professional external wall insulation systems are designed to transform cold, inefficient properties into energy efficient and comfortable homes. EWI systems work by insulating external walls to form a protective thermal building envelope, helping your property stay warm, reducing heat loss and lowering energy bills.

What are external wall insulation systems?

External wall insulation involves fixing an insulation layer to the outside of an existing wall, then applying a reinforced base coat and decorative finish. These insulation systems are designed for properties with solid walls or where cavity walls are unsuitable.

The system covers the entire face of the exterior walls, including areas around windows, doors and door reveals, creating a continuous thermal envelope around the building.

Benefits of external wall insulation

• Helps significantly reduce heat loss through external walls.
• Improves the thermal performance of the property.
• Makes your home warmer and more energy efficient.
• Can lower heating costs and heating bills.
• Reduces carbon emissions and supports sustainable building.
• Helps relieve fuel poverty by reducing heating demand.
• Enhances the building fabric and adds long-term property value.

Lower heating costs and reduced energy bills

By upgrading your property with external insulation, you reduce unwanted heat loss and improve thermal efficiency. This lowers overall energy consumption and reduces reliance on heating systems, keeping your home warmer for longer.

External vs internal wall insulation

Compared with internal wall insulation, installing EWI systems on the outside avoids reducing internal living space. It also protects the structure from water ingress, weathering and damp problems, helping prevent condensation and improving the condition of the entire building envelope.

External systems also enhance building maintenance by shielding the existing façade and improving long-term durability of the existing building.

Choosing the right insulation board for external walls

Your choice of insulation boards will depend on the property type, existing wall condition, project goals and structural requirements.

• Expanded polystyrene (EPS) – lightweight, cost-effective and widely used.
• Mineral-based boards – offering improved fire resistant properties.
• Natural materials such as wood fibre for breathable, low-carbon builds.

Each insulation material is selected based on thermal performance, moisture movement, and compatibility with the building substrate.

Improving U-value and meeting building regulations

Our systems are engineered to improve the U value and meet or exceed current building regulations. By adding a high-performance insulation layer, your property becomes more thermally efficient while reducing long-term heating and maintenance risks.

Our technical team can help you calculate U-values, assess thickness requirements and advise on the right system for your project.

Planning permission and installation considerations

Some properties may require planning permission, especially listed buildings or properties in conservation areas. Our team can provide guidance on whether your external wall insulation project will need approval.

During installation, key factors include:

• Double-checking suitability of the existing wall and substrate.
• Incorporating details such as corner bead protection.
• Managing water vapour movement to avoid damp and condensation.
• Ensuring protection around windows, doors and rooflines.

EWI is one of the most effective ways to insulate and future proofing your property against rising energy costs and climate change.

If you need support choosing the right system or understanding installation method options, our technical team is available for expert advice and guidance.