INCA EWI Case Study: Polish Community Centre, Coventry

Improving thermal performance through a combined cavity wall insulation and EWI Pro system.

Project Overview

A Community Building Thermal Upgrade in Coventry

The Coventry Polish Community Centre project involved the installation of an EWI Pro external wall insulation system as part of a wider thermal upgrade to improve the energy efficiency of the building.

The client’s brief was to make the building as energy efficient as possible. To achieve this, the project combined cavity wall insulation with a 60mm EPS EWI Pro system, finished with a silicone render. This approach helped improve the thermal performance of the external walls while also providing the building with a refreshed, durable and weather-resistant façade.

Before the insulation works, the building had a U-value of 1.36 W/m²K. Following the installation of Instafibre-34 within the 70mm cavity and the 60mm EPS external wall insulation system, the wall build-up achieved an improved U-value of 0.24 W/m²K.

Rockwarm Insulation Ltd carried out the installation between October and December 2025, with EWI Pro supporting the project through U-value calculations, specification guidance, technical input and site visits for quality control.

The completed project delivered a significant improvement in thermal performance, helping support the long-term comfort and energy efficiency of this important community building.

Key Project Details

System Selection

EPS External Wall Insulation with Silicone Render Finish

The Coventry Polish Community Centre was specified with a 60mm EPS EWI Pro system, installed alongside cavity wall insulation to help improve the overall thermal performance of the building.

EPS was selected as the external wall insulation layer due to its suitability for improving wall insulation performance while forming part of a complete EWI Pro render system. The 60mm EPS boards were installed externally, creating an insulated façade build-up ready for the reinforced basecoat and final silicone render finish.

The project also included the installation of Instafibre-34 within the existing 70mm cavity. By combining cavity wall insulation with external wall insulation, the project was able to achieve a notable U-value improvement, reducing heat loss through the walls and helping support a more energy-efficient building.

The silicone render finish provided the final decorative and protective layer, helping improve the appearance of the building while offering long-term weather resistance.

Why This System Worked

• Combined Insulation Approach – The project used both cavity wall insulation and external wall insulation to help improve the building’s thermal performance.
• EWI Pro EPS System – The 60mm EPS system provided an external insulation layer as part of the wider façade upgrade.
• Silicone Render Finish – The final silicone render helped protect the façade from weather exposure while providing a clean, refreshed external appearance.

A combined cavity and external wall insulation approach helped improve the building’s thermal efficiency and external finish.

EWI Pro’s Role in the Project

Technical Support from U-Value Calculations Through to Site Visits

EWI Pro supported the Coventry Polish Community Centre project through U-value calculations, specification input, technical guidance and site visits for quality control. At the specification stage, EWI Pro helped assess the proposed insulation approach and supported the project team with U-value calculations. This helped demonstrate the expected improvement in thermal performance, with the wall build-up improving from 1.36 W/m²K before insulation to 0.24 W/m²K after the combined cavity and external wall insulation works. EWI Pro also provided project-specific specification support to help ensure the correct system approach was selected for the building. As works progressed, site visits were carried out to review installation quality and provide technical guidance where required. This support helped give the project team confidence that the specified system was being installed consistently and in line with the intended build-up.

EWI Pro Support

• U-Value Calculations – EWI Pro calculated wall build-up thermal performance before and after insulation works.
• Specification Support – Technical input helped support the correct EWI Pro system approach for the building.
• Site Visits – EWI Pro attended site to provide practical guidance during the installation process.
• Quality Control – Site inspections helped monitor installation quality and support consistency across the façade.

From thermal calculations to site support, EWI Pro helped guide the project from specification through to installation.

System Build-Up

EPS onto Red Brick Silicone Render System

The external wall insulation element of the Coventry Polish Community Centre project used an EWI Pro EPS system installed onto the existing red brick substrate.

The red brick provided the masonry background for the external wall insulation system. 60mm EPS insulation boards were installed externally to help reduce heat loss through the building fabric and support the wider energy efficiency upgrade.

Once the EPS insulation was in place, the system was reinforced with a basecoat layer and embedded fibreglass mesh. This helped create a strong, stable surface ready for the final render finish.

The façade was then prepared with render primer and completed with a silicone render finish, providing the building with a durable, weather-resistant and refreshed external appearance.

EPS on Red Brick Build-Up

1. Substrate Preparation
2. Starter Track
3. Insulation Adhesive
4. Mechanical Fixings
5. Expanded Polystyrene (EPS)
6. Basecoat Reinforcement Layer
7. Fibreglass Mesh
8. Topcoat Primer
9. Silicone Render

Why This Build-Up Worked

• Suitable Masonry Substrate – The system was installed onto the existing red brick, providing a solid masonry background for the EWI Pro system.
• 60mm EPS Insulation – The EPS insulation formed the external insulation layer, helping reduce heat loss through the building envelope.
• Reinforced Base Layer – Basecoat and fibreglass mesh created a strengthened layer over the insulation boards.
• Durable Render Finish – The silicone render provided the final protective and decorative finish for the completed façade.

A complete EPS onto red brick system build-up, finished with silicone render for a durable and thermally improved façade.

System Components

Materials Used Across the Build-Up

The Coventry Polish Community Centre project used a combination of cavity wall insulation and an EWI Pro external wall insulation system to improve thermal performance and refresh the building’s external appearance.

Each component played an important role in the completed build-up, from the Instafibre-34 cavity insulation and 60mm EPS boards through to the adhesive, reinforced basecoat, mesh, primer and silicone render finish.

Together, the system components helped deliver a thermally improved and durable façade finish for the community centre.

Component Breakdown

• Instafibre-34 – Installed within the 70mm cavity to help improve the thermal performance of the wall build-up.
• 60mm EPS Insulation – Provided the external insulation layer as part of the EWI Pro system.
• Mechanical Fixings – Helped secure the EPS insulation boards as part of the specified system.
• EWI-220 EPS Basecoat – Used to bond EPS boards and create a reinforced basecoat ready for the render finish.
• Fibreglass Mesh – Embedded into the basecoat to improve reinforcement and façade durability.
• EWI-333 Topcoat Primer – Prepared the reinforced basecoat for the final silicone render application.
• EWI-075 Silicone Render – Provided the final decorative and protective finish for the upgraded façade.

Project Outcome

Improved Thermal Performance with a Refreshed External Finish

The completed Coventry Polish Community Centre project demonstrates how a combined insulation approach can help improve the thermal performance of an existing building.

By insulating the 70mm cavity with Instafibre-34 and installing a 60mm EPS EWI Pro system externally, the project achieved a significant U-value improvement. The wall build-up improved from 1.36 W/m²K before insulation to 0.24 W/m²K after the works were completed.

The silicone render finish also helped refresh the appearance of the building, creating a clean and durable external façade while supporting long-term weather protection.

EWI Pro’s involvement through U-value calculations, specification guidance, site visits and quality control helped support the project from the early technical stages through to installation. This ensured the selected system was suitable for the building and helped the project team deliver a consistent finish on site.

Key Project Outcomes

• U-Value Improvement – The wall build-up improved from 1.36 W/m²K to 0.24 W/m²K.
• Combined Insulation Upgrade – The project used both cavity wall insulation and external wall insulation to improve thermal performance.
• Technical Support – EWI Pro supported the project with U-value calculations, specification input and site visits.
• Refreshed External Finish – The silicone render finish gave the building a clean, durable and weather-resistant façade.

The completed project combined improved thermal performance, technical support and a durable silicone render finish.

More Than a Building

Supporting Heritage, Community and Connection in Coventry

The Coventry Polish Community Centre has been an important part of the city’s community since the 1960s, providing a welcoming space where people of all ages can come together to connect, learn and celebrate their shared heritage.

For many members of Coventry’s Polish community, the centre represents far more than a building. It serves as a cultural and social hub where traditions, language and customs can be maintained and passed on to future generations. Through regular events, celebrations, educational activities and community gatherings, the centre helps ensure that Polish heritage remains a vibrant part of community life.

Alongside its cultural role, the centre provides valuable opportunities for social interaction, learning and personal development. It offers a place where individuals and families can build relationships, access support networks and participate in activities that promote wellbeing and inclusion.

The centre also plays an important role in the wider Coventry community. By creating opportunities for people from different backgrounds to come together, it helps reduce social isolation, encourages integration and strengthens community connections. Its welcoming environment enables both long-standing residents and newcomers to feel part of a supportive and active community.

Investing in the building’s future through energy efficiency improvements helps ensure that the centre can continue delivering these benefits for many years to come. The refurbishment has created a warmer, more comfortable and more sustainable environment, supporting the organisation’s ability to serve future generations.

“Community buildings like the Coventry Polish Community Centre play a vital role in bringing people together, preserving cultural heritage and supporting local communities. We are proud to have helped improve the building’s thermal performance and long-term sustainability, ensuring it can continue serving future generations in a warmer, more comfortable and energy-efficient environment.”

Tyler Cooper
Head of Business Development Capital Schemes, EWI Pro

The Coventry Polish Community Centre continues to play a vital role in preserving heritage, bringing people together and supporting future generations in a warmer, more sustainable space.