Polystyrene EPS Graphite Insulation Board 80mm – Thermal Bridging Reduction

Product Overview

Professional-grade polystyrene eps grafit 80mm UK boards are the high-performance standard for modern External Wall Insulation (EWI) systems. Enhanced with integrated high-purity graphite particles, these boards reflect radiant heat to deliver significantly higher thermal efficiency than traditional white EPS. With a low thermal conductivity of 0.031 W/mK, this 80mm variant is specifically engineered for effective thermal bridging reduction UK in both new build and renovation projects. Designed as a critical system component, it enables properties to meet stringent UK energy standards and Part L regulations when installed as part of a fully certified façade solution.

Key Benefits

• Superior Thermal Performance: Low thermal conductivity of 0.031 W/mK for maximum energy retention.
• Enhanced Efficiency: Delivers up to 20% better insulation values than standard white polystyrene of the same thickness.
• Lightweight Handling: At only 1.5kg per m², boards are easy to transport, cut, and install on-site.
• High Dimensional Stability: Resistant to shrinking or warping, ensuring a flat and secure base for rendering.
• Moisture Resistance: Closed-cell structure limits water absorption while maintaining vapour permeability for building health.
• System Compatibility: Fully tested for use with premium adhesives, reinforcement mesh, and silicone renders.

Technical Specifications

Property	Value
Thickness	80 mm
Board Dimensions	1000 mm x 500 mm
Coverage per Board	0.5 m²
Thermal Conductivity (λ)	0.031 W/mK
Thermal Resistance (R-Value)	2.58 m²K/W
Compressive Strength	70 kPa
Density	15 kg/m³
Reaction to Fire	Class E (EN 13501-1)
Standard Compliance	EN 13163

Application & Compatibility

• Ideal for use in External Wall Insulation (EWI) systems on masonry, brick, and timber-frame substrates.
• Specifically designed for rendered façade systems requiring high thermal performance with minimal wall thickness.
• Compatible with Atlas and Ceresit adhesive mortars, basecoats, and mechanical fixings.
• Suitable for retrofit energy-efficiency upgrades and new-build thermal envelopes.
• Note: Not suitable for use below the Damp Proof Course (DPC) or on high-rise buildings requiring non-combustible A1 insulation.

Installation Notes

Boards must be secured to a clean, structurally sound substrate using a combination of specialist adhesive mortar and mechanical fixings. To ensure a professional finish and eliminate cold spots, boards should be installed in a staggered "brick-bond" pattern with tight-fitting joints. Before applying the basecoat and mesh, the outer surface of the board must be rasped or sanded to create an abrasive surface for optimal mechanical bonding. Boards should be covered with the basecoat as soon as possible to protect against UV degradation.

Is This Product Right for Your Project?

• Choose this product if: You are looking for a cost-effective, high-performance insulation layer to meet UK building regulations with a slim profile.
• Consider alternatives if: Your project is a high-rise building or requires the highest fire safety rating; in these cases, please view our mineral wool insulation options.

Frequently Asked Questions

How many 80mm boards do I need per square metre?

Each board covers exactly 0.5m², so you will need 2 boards for every 1m² of wall area. We recommend adding 5-10% extra for cutting and waste.

Does this board require mechanical fixings?

Yes. For 80mm thickness in UK EWI systems, mechanical fixings (insulation plugs) are required alongside adhesive to ensure structural stability against wind loading.

Can I use this board for internal wall insulation?

While primarily designed for external use, these boards can be used internally if fitted as part of a correctly designed dry-lining or batten system with appropriate fire protection.

For more information on full system builds, explore our wider range of EPS insulation boards and compatible basecoats.