Expanded Cork Granules are an ultra-lightweight, 100% natural insulation material derived as a by-product from the production of expanded insulation cork boards. These granules are perfect for use in lime screeds, floor voids, cavity insulation, and other areas where breathable, sustainable, and high-performance insulation is required.
Offering a thermal conductivity of 0.040–0.041 W/m·K and a density of just 60–70 kg/m³, cork granules combine exceptional insulation properties with minimal environmental impact. They are fully recyclable, biodegradable, and carbon-negative, making them ideal for natural building, conservation, and eco-renovation projects.
✅ Key Features
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100% Natural & Renewable – Sourced from the bark of cork oak trees without felling
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Thermal Conductivity: 0.040–0.041 W/m·K
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Density: 60–70 kg/m³
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Fire Reaction: Euroclass E
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Excellent Acoustic Insulation – Naturally dampens vibration and sound transmission
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Highly Breathable – Supports vapour diffusion, ideal for solid-wall structures
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Durable & Stable – Maintains insulation properties over time
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Non-Toxic – Free from synthetic resins, binders, or VOCs
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Carbon-Negative – Each harvest helps offset atmospheric CO₂
📦 Product Options
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Grain Sizes: 3–10 mm
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Packaging: Supplied in 250L bags
🛠️ Common Applications
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🔹 Floor Joist Voids – Loose-fill insulation in suspended floors
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🔹 Internal Wall Cavities – Ideal for vapour-open retrofits
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🔹 Roof Spaces & Attic Insulation
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🔹 Vibration Isolation & Acoustic Control – Under machinery, HVAC, or subfloors
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🔹 Packing and Lightweight Fills – Natural alternative to synthetic fillers
What is Cork?
Cork is the bark of the cork oak (Quercus suber L.), a unique tree native to the Mediterranean basin. Cork is composed of a microscopic honeycomb of gas-filled cells, lined with suberin and lignin, making it light, resilient, and naturally insulating. A single cubic centimetre contains nearly 40 million cells, contributing to its extraordinary thermal, acoustic, and mechanical properties.
Harvested every 9 years without harming the tree, cork bark regenerates naturally. Each cork oak can live for 200 years and be harvested up to 17 times—making cork one of the world’s most sustainable building materials.
Environmental Benefits
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♻️ Fully Recyclable & Biodegradable
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🌬️ VOC-Free & Non-Toxic
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🌱 Chemical-Free & Breathable
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🌳 Supports Biodiversity & Rural Economies
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🟢 Carbon Sink Material – Each m³ of cork stores carbon and reduces atmospheric CO₂
