Eurowall® +: Tongue & Groove Insulation for Thermal and Wind Protection
Eurowall® + insulation boards feature precision tongue & groove joints for reduced thermal bridging, improved windtightness, and protection against wind-driven rain.
Cavity wall insulation plays a vital role in improving thermal efficiency of a building envelope. According to the Energy Saving Trust, up to 35% of a property’s heat can escape through uninsulated or poorly insulated walls. Correctly installed insulation improves thermal performance, energy efficiency, and indoor comfort.
Future Homes Standard: What It Means for Insulation in the UK
The UK government is expected to introduce the Future Homes Standard (FHS) in late 2025, a major step toward building more energy-efficient, low-carbon homes.
While the final details are still being confirmed, the aim of the FHS is clear: to ensure that new homes are “zero carbon ready”. This means they will be designed to operate without carbon emissions as the national electricity grid continues to decarbonise.
Why Insulation Is at the Heart of the Future Homes Standard
Insulation isn’t just about keeping warm - it is central to making homes more energy-efficient and reducing heating costs.
The FHS sets ambitious targets, aiming to cut carbon emissions from new homes by 75–80% compared to current standards. To achieve this, it focuses on two key areas:
- Better building fabric - using high-performance insulation, airtight construction, and smart design to reduce heat loss.
- Low-carbon heating systems - like heat pumps, which are more efficient and environmentally friendly than traditional boilers.
To meet FHS requirements, builders will need to:
✅ Use insulation that conforms to SAP requirements in walls, roofs, and floors (with lower U-values).
✅ Improve junction detailing to reduce thermal bridging.
✅ Design ventilation systems that maintain good indoor air quality while keeping heat in.
Fabric-First and Compliance
In accordance with Approved Document L (England) and equivalent regional standards, the fabric-first approach prioritises reducing energy demand through highly thermally efficient building envelopes before introducing renewable technologies.
PIR insulation provides high thermal resistance relative to thickness compared with traditional mineral-based insulants. Its' dimensional stability ensures consistent thermal performance over time when installed according to design specifications.
By helping achieve lower U-values within standard cavity dimensions, Eurowall® + assists designers and specifiers in meeting Part L requirements and fabric energy efficiency targets as part of a compliant, energy-efficient wall system.
The Plus That Makes the Difference
- Suitable for full-fill masonry cavity walls with a minimum 10 mm residual cavity
- BBA certified for defined applications (refer to the current certificate)
- Tongue and groove joints on all edges for a close, reliable fit
- Foil facings to enhance thermal performance
- Can contribute to U-values of 0.18 W/m²·K or better in standard cavity constructions (design dependent)
- Available in 75 mm, 90 mm, 115 mm, and 140 mm thicknesses
- Compatible with conventional bricklaying techniques
Product performance values are based on testing and certification data available at the time of publication. Actual performance depends on design, detailing, and workmanship.
Recticel’s PIR-fect Solution
Eurowall® + is a precision-engineered PIR foam board with low-emissivity aluminium foil facings on both sides. It is available in 75 mm, 90 mm, 115 mm, and 140 mm thicknesses, providing flexibility for a wide range of wall constructions. Each board features tongue and groove joints on all four edges, supporting a continuous thermal layer and helping to reduce thermal bridging at board joints.
Thermal Performance
PIR insulation achieves a thermal conductivity (λ-value) as low as 0.022 W/m·K, depending on thickness and facing material.
In standard masonry cavity wall constructions, a 90 mm Eurowall® + board can contribute toward achieving a U-value of 0.18 W/m²·K in a 100 mm cavity wall while maintaining a minimum 10 mm residual air gap.
These values are indicative and depend on wall design, materials, and installation quality. Final U-values should always be verified through project-specific thermal calculations in accordance with BS EN ISO 6946 and relevant building regulations, these are available via our Technical Department.
Installation and Use
Eurowall® + boards are designed for installation using conventional bricklaying techniques. The tongue and groove edges provide a tight interlocking fit, reducing the risk of gaps and ensuring continuity across the insulation layer.
Boards should be closely butted both vertically and horizontally, with care taken to maintain the minimum residual cavity defined in the design. While general board joints typically do not require taping, corners, openings, and penetrations will require specific treatments as outlined in Recticel’s installation instructions and the BBA certificate.
Eurowall® + should always be installed in accordance with Recticel’s installation guide and relevant building regulations.