Applications

Cork-based thermal insulating stucco combining recycled cork, natural hydraulic lime (NHL 5), perlite, cellulose, and pumice into a single machine- or trowel-applied system. Serves as both continuous insulation and a finish-ready substrate for interior plaster or exterior stucco. No foam, no boards, no joints. Ideal for exterior retrofit of masonry and stuccoed properties, and exceptionally well-suited for historic buildings where moisture management is critical.

Advantages

• Made with rapidly renewable recycled cork, natural hydraulic lime, and other natural ingredients; low carbon footprint with no gypsum, cement, or concrete
• Highly vapor permeable with the ability to actively absorb and release moisture, preventing condensation and protecting masonry from long-term moisture damage
• Natural hydraulic lime composition is inherently alkaline, inhibiting mold and fungal growth and supporting healthy indoor air quality
• Monolithic, joint-free application provides superior crack resistance compared to conventional stucco systems
• Extremely lightweight at 15.6 lb/ft³ (250 kg/m³) relative to its insulation value
• Fast to apply by machine or trowel, with a 40-minute workability window
• Two-in-one system: continuous insulation and stucco substrate combined into a single assembly, applicable over existing plaster
  
• Contributes to LEED credits; certified by Indoor Air Comfort® ideal for historic interior restoration and exterior retrofits

Properties

• Expected Thermal Resistance (R): R-3.9 per inch (0.270 m²K/W per cm)
• Expected Thermal Conductivity (λ): 0.243 BTU·in/(hr·ft²·°F) (0.035 W/mK)
  
• Density: 15.6 lb/ft³ (250 kg/m³) (±15%)
• Compressive Strength: 406 psi (2.8 N/mm²) (EN 998-1, Category CS II)
  
• Composition: Recycled cork, natural hydraulic lime NHL 5, expanded amorphous silica, perlite, pumice
• Application: Machine- or trowel-applied; min. thickness 0.6 inch (1.5 cm), max. per layer 1.6 inch (4 cm)

• R-value: R-3.9 per inch (λ = 0.037 W/mK)
• Coverage: 1.35 lb/ft² (2.60 kg/m²) per inch of thickness
• Delivery size: 33 lb (15 kg) paper bags, 60 bags per pallet
• Expected in stock: July 2026

It can go on a wide variety of substrates including brick, stone, block, concrete, existing stucco, wood sheathing, and straw bale. It works externally as an insulating stucco system or internally as an insulating wall finish. Primary applications are historic masonry retrofits and solid-wall buildings where vapor diffusion is non-negotiable, but it's equally at home on any new construction project where a natural, insulating stucco system makes sense.

It is applied similarly to stucco, but in layers up to 1.6" (4 cm) per coat. Apply this lightweight insulation render by hand trowel or spray machine. Most larger projects will be spray-applied using a standard stucco sprayer/pump. Fiberglass mesh is embedded at the midpoint for any total application thickness over 2⅜" (60 mm), or on movement-prone substrates such as wood-framed and straw bale walls. No specialist trade beyond an experienced stucco or plaster applicator is required. The system is commonly finished with Diasen Argatherm skim coat and a vapor-permeable, breathable paint which also ensures full system warranty coverage.

The product carries CE marking, EN testing, UKCA certification and has been widely used across Europe and the UK. The lambda value of 0.037 W/mK converts to approximately R-3.9 per inch, a meaningful contribution when applied at typical stucco thicknesses. North American testing is currently underway, including thermal resistance and fire behavior. We expect full results by end of summer 2026 and will update the team as they come in. In the meantime, email or call us directly with questions.