210mm Rockwool EWI External Wall DD Slab

210mm Rockwool EWI External Wall DD Insulation Slab delivers professional-grade thermal protection for external wall insulation systems with established third-party certification.

Engineered with Rockwool's patented Dual Density technology, these slabs feature a reinforced outer layer and flexible inner core. The high-density surface provides excellent support for render and fixture installation, whilst the softer underside accommodates substrate variations and minor imperfections.

When installed with tight joints, the slabs create a seamless thermal envelope that eliminates heat loss through gaps and thermal bridging.

Specifying 210mm Rockwool DD insulation in your wall insulation project ensures lasting performance and reliability. Stone wool insulation from Rockwool delivers proven durability, with documented performance extending beyond 55 years.

Product specification

• Brand: Rockwool®
• Model: 210mm EWI
• Thickness: 210mm
• Dimensions: 1,200mm x 600mm x 210mm
• Length: 1200mm
• Width: 600mm
• Board Coverage: 0.72m2
• Colour: Pale white
• Density: 110kg/m3
• Compressive strength: ≥ 10 kPa
• Tensile strength: ≥ 10 kPa
• R-Value: 1.39m2K/W
• Thermal Conductivity: 0.036W/mK
• Material: Molten volcanic rocks
• Profile: Square edge
• Temperature resistance: up to 1000ºC
• Fire Classification: A1 Non-combustible
• Shipping method: Articulated Vehicle ǀ Courier
• Applications: External Wall Insulation Systems
• Features: Thermal and Acoustic Insulation Slab
• Manufacturer: ROCKWOOL®

The 210mm Rockwool External Wall Dual Density Slab combines precision engineering with proven performance for external wall applications. These 210mm external wall insulation boards incorporate dual density construction with two distinct wool layers of different densities: a lower density core for accommodating substrate irregularities, and a higher density facing layer ideal for render application. Installation requires mechanical fixings combined with quality adhesive, with a minimum of 7 fixings per square meter recommended for secure attachment.

Application

Install 210mm Rockwool Mineral Wool insulation slabs according to manufacturer guidelines, which detail design specifications and installation procedures. For optimal bonding, secure boards using mortar or adhesive alongside mechanical fixings.

Given the substantial weight of mineral wool products, we recommend the EWI-225 Premium Basecoat over standard adhesives designed for lighter materials. Apply a thin primer coat to prepared surfaces, then once cured, apply the basecoat and set the Fibreglass Mesh.

Non-combustible

210mm Rockwool stone wool achieves the highest 'A1 – Non-combustible' rating under European fire classification standards, preventing ignition and flame propagation.

Durable

1. 210mm Rockwool DD slabs remain dimensionally stable throughout the building's lifespan, resisting shrinkage and deterioration.
2. The dense outer surface supports reliable basecoat adhesion and prevents fastener over-driving.
3. Delivers superior resistance to wind and rain exposure during the installation phase.
4. Proven track record: 210mm Rockwool has performed reliably in European EWI systems for more than 40 years.

Breathable

• 210mm Rockwool stone wool features an open-cell structure allowing water vapour to pass through, whilst water-repellent fibres prevent moisture penetration.
• Provides vapour resistance equivalent to still air.

Thermal performance

Tightly butted joints allow fibres to interlock effectively, preventing heat loss through gaps and thermal weak points.

Acoustic performance

• 210mm Rockwool slabs in EWI systems increase building envelope mass, reducing sound and vibration transmission.
• The fibrous matrix contributes to sound absorption, with testing showing up to 8 dB improvement in weighted sound reduction, Rw (substrate dependent).

Dual Density Slabs for External Walls

• Purpose-built for external wall insulation systems, Dual Density Slabs provide a premium stone wool insulation solution.
• Manufactured using ROCKWOOL's proprietary dual density process, these slabs feature an enhanced density top layer. This creates a robust surface for render and fixture installation, whilst the compliant underside adapts to substrate variations.
• The top layer is clearly marked 'THIS SIDE UP' for straightforward installation and correct orientation.

More Information on 210mm Rockwool External Wall DD Slab

• Manufacturer Link: Rockwool DD
• 210mm Rockwool External Wall DD Slab offers high-performance insulation across diverse applications.
• Browse our full Rockwool Insulation range and filter by thickness or coverage using the sidebar. For project-specific advice or bulk quotations, contact our team by phone on +4402038839057, email sales@insulationbee, or use Live Chat – Competitive UK Rockwool Insulation Pricing.