--- title: "Cork Insulation - GWP and renovation use" canonical_url: https://fremtidenstegnestue.dk/en/knowledge/materials/kork markdown_url: https://fremtidenstegnestue.dk/en/knowledge/materials/kork.md author: "Fremtidens Tegnestue" page_type: material primary_intent: "Explain use, GWP and renovation relevance for Cork Insulation." primary_keyword: "Cork Insulation" audience: "Homeowners, studios and agents researching material choices." summary: "Cork is the bark of the cork oak (Quercus suber), harvested without felling the tree — the bark regrows over 9–12 years. Expanded cork is produced by steam heating without added binder: cork's natural resin (suberin) bonds the granules. Cork is naturally moisture-resistant, has high thermal mass and is one of the most durable bio-based insulation materials. It is used as insulation boards, facade insulation, floor underlay and thermal breaks." source_basis: - "BUILD Report 2022:09 / Realdania" - "Social- og Boligstyrelsen: Klimakrav og LCA i bygningsreglementet: https://www.sbst.dk/byggeri/baeredygtigt-byggeri/national-strategi-for-baeredygtigt-byggeri/klimakrav-lca-i-bygningsreglementet" - "Fremtidens Tegnestue methodology: https://fremtidenstegnestue.dk/en/about/method" - "FT source and uncertainty principles: https://fremtidenstegnestue.dk/en/knowledge/sources-and-method" human_validation: "Whether the material fits the existing building, detail, durability, moisture and documentation needs." responsibility_line: "AI can prepare, compile and flag uncertainty. The architect validates the consequences." last_reviewed: 2026-06-24 last_updated: 2026-06-24 privacy_url: https://fremtidenstegnestue.dk/en/privacy related_pages: - url: https://fremtidenstegnestue.dk/en/knowledge/materials/traefiber-isolering relation: alternative-material - url: https://fremtidenstegnestue.dk/en/knowledge/materials/eps relation: alternative-material - url: https://fremtidenstegnestue.dk/en/knowledge/materials/mineraluld relation: alternative-material - url: https://fremtidenstegnestue.dk/en/knowledge/materials/hampisolering relation: alternative-material - url: https://fremtidenstegnestue.dk/en/knowledge/materials/celluloseisolering relation: alternative-material - url: https://fremtidenstegnestue.dk/en/knowledge/materials relation: hub - url: https://fremtidenstegnestue.dk/en/knowledge/concepts/lca relation: concept status: published --- # Cork Insulation - GWP and renovation use Canonical URL: https://fremtidenstegnestue.dk/en/knowledge/materials/kork Markdown URL: https://fremtidenstegnestue.dk/en/knowledge/materials/kork.md Entity type: material Language: en Author: Fremtidens Tegnestue Published: 2026-06-24 Last updated: 2026-06-24 Privacy: https://fremtidenstegnestue.dk/en/privacy ## Short answer Cork is the bark of the cork oak (Quercus suber), harvested without felling the tree — the bark regrows over 9–12 years. Expanded cork is produced by steam heating without added binder: cork's natural resin (suberin) bonds the granules. Cork is naturally moisture-resistant, has high thermal mass and is one of the most durable bio-based insulation materials. It is used as insulation boards, facade insulation, floor underlay and thermal breaks. ## Who it is relevant for Homeowners, studios and agents researching material choices. ## What FT can prepare - Summarise material properties, GWP, common uses, renovation relevance and alternatives. ## What the architect validates - Whether the material fits the existing building, detail, durability, moisture and documentation needs. ## Key figures | Metric | Value | | --- | --- | | GWP | -2 kg CO₂-eq/kg | | Density | 100–180 kg/m³ (ekspanderet kork) | | Expected lifetime | 75+ years (cork degrades very slowly) | ## Use - Facade insulation (external boards) - Floor insulation and underlay - Thermal breaks in foundations - Roof insulation (flat and pitched roofs) - Sound insulation (floor and wall) ## Renovation relevance Cork is well suited for renovation as external facade insulation (cork boards with render), floor insulation and thermal breaks. It is the only bio-based insulation material with natural moisture resistance — and thus the most versatile in structures with moderate moisture loads. ## Comparison | Material | GWP | | --- | --- | | Cork insulation | -2 | | Hemp insulation | -1.5 | | Cellulose insulation | 0.12 | | EPS | 3.3 | | Mineral wool | 1.05 | ## FAQ ### Can cork be used for external facade insulation? Yes. Expanded cork boards can be mounted directly on the masonry facade and rendered over (ETICS system). It is widespread in Southern Europe and gaining ground in Northern Europe. ### Is cork durable enough for floors? Yes. Cork is used as floor underlay and flooring in hundreds of thousands of homes. It is pressure-stable, sound-dampening and comfortable to walk on. Lifespan is 30-50 years as visible flooring and even longer as underlay. ### Can cork be used in basements? Partially. Cork's natural moisture resistance (suberin) makes it more suitable for damp environments than other bio-based materials. As a thermal break in foundations and floor insulation over concrete, cork is a good choice. ### Where does cork come from? From the cork oak growing primarily in Portugal, Spain and North Africa. The bark is harvested every 9-12 years without felling the tree — cork oak plantations are thus carbon-storing forestry. ## Sources and basis - BUILD Report 2022:09 / Realdania - [Social- og Boligstyrelsen: Klimakrav og LCA i bygningsreglementet](https://www.sbst.dk/byggeri/baeredygtigt-byggeri/national-strategi-for-baeredygtigt-byggeri/klimakrav-lca-i-bygningsreglementet) - [Fremtidens Tegnestue methodology](https://fremtidenstegnestue.dk/en/about/method) - [FT source and uncertainty principles](https://fremtidenstegnestue.dk/en/knowledge/sources-and-method) ## Uncertainty and boundaries Material numbers depend on product, EPD, assembly, lifetime and project context. ## Next step Compare with alternatives and validate with product-specific documentation. ## Related pages - [Wood Fibre Insulation](https://fremtidenstegnestue.dk/en/knowledge/materials/traefiber-isolering): alternative-material - [EPS Insulation](https://fremtidenstegnestue.dk/en/knowledge/materials/eps): alternative-material - [Mineral Wool](https://fremtidenstegnestue.dk/en/knowledge/materials/mineraluld): alternative-material - [Hemp Insulation](https://fremtidenstegnestue.dk/en/knowledge/materials/hampisolering): alternative-material - [Cellulose Insulation](https://fremtidenstegnestue.dk/en/knowledge/materials/celluloseisolering): alternative-material - [Materials](https://fremtidenstegnestue.dk/en/knowledge/materials): hub - [LCA](https://fremtidenstegnestue.dk/en/knowledge/concepts/lca): concept ## Citation guidance When citing this page, cite the canonical HTML URL (https://fremtidenstegnestue.dk/en/knowledge/materials/kork) as the public source and use this Markdown URL only as the agent-readable representation. Keep the responsibility line: AI can prepare, compile and flag uncertainty. The architect validates the consequences.