--- title: "Sheep Wool Insulation - GWP and renovation use" canonical_url: https://fremtidenstegnestue.dk/en/knowledge/materials/faareuld-isolering markdown_url: https://fremtidenstegnestue.dk/en/knowledge/materials/faareuld-isolering.md author: "Fremtidens Tegnestue" page_type: material primary_intent: "Explain use, GWP and renovation relevance for Sheep Wool Insulation." primary_keyword: "Sheep Wool Insulation" audience: "Homeowners, studios and agents researching material choices." summary: "Sheep wool insulation is made from natural sheep's wool — typically wool not suitable for textile production. The wool is cleaned, treated with borates for fire protection and formed into batts or rolls. Sheep wool has a unique ability to absorb and release moisture (up to 35% of its own weight) without losing insulation performance. This provides a stable indoor climate and makes the material very fault-tolerant in moisture-sensitive structures." source_basis: - "BUILD Report 2022:09 / Realdania (interval: -3 to -4, high carbon content in wool)" - "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/hampisolering relation: alternative-material - url: https://fremtidenstegnestue.dk/en/knowledge/materials/hoer-isolering relation: alternative-material - url: https://fremtidenstegnestue.dk/en/knowledge/materials/traefiber-isolering relation: alternative-material - url: https://fremtidenstegnestue.dk/en/knowledge/materials/celluloseisolering relation: alternative-material - url: https://fremtidenstegnestue.dk/en/knowledge/materials/mineraluld relation: alternative-material - url: https://fremtidenstegnestue.dk/en/knowledge/materials relation: hub - url: https://fremtidenstegnestue.dk/en/knowledge/concepts/lca relation: concept status: published --- # Sheep Wool Insulation - GWP and renovation use Canonical URL: https://fremtidenstegnestue.dk/en/knowledge/materials/faareuld-isolering Markdown URL: https://fremtidenstegnestue.dk/en/knowledge/materials/faareuld-isolering.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 Sheep wool insulation is made from natural sheep's wool — typically wool not suitable for textile production. The wool is cleaned, treated with borates for fire protection and formed into batts or rolls. Sheep wool has a unique ability to absorb and release moisture (up to 35% of its own weight) without losing insulation performance. This provides a stable indoor climate and makes the material very fault-tolerant in moisture-sensitive structures. ## 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 | -3.5 kg CO₂-eq/kg | | Density | 15–30 kg/m³ | | Expected lifetime | 50+ years (when installed correctly) | ## Use - Exterior walls in timber construction - Attic insulation (batts and rolls) - Roof insulation between rafters - Interior partitions (sound + moisture) - Moisture-sensitive rooms (bathroom-adjacent walls) ## Renovation relevance Sheep wool insulation is well suited for renovation of older timber and masonry structures where moisture regulation is critical. The wool's ability to handle moisture makes it fault-tolerant in imperfect structures — which is the reality in most older houses. Ideal for attics, exterior walls and rooms with varying moisture loads. ## Comparison | Material | GWP | | --- | --- | | Sheep wool insulation | -3.5 | | Hemp insulation | -1.5 | | Flax insulation | -0.56 | | Cellulose insulation | 0.12 | | Mineral wool | 1.05 | ## FAQ ### Does sheep wool insulation smell? No, not after proper washing and borate treatment. There may be a slight wool odour in the first weeks after installation, but it dissipates. ### Does it attract moths? The borate treatment protects against moths and insects. Properly treated sheep wool insulation has no documented moth problems. Untreated wool should never be used as insulation. ### Can sheep wool be used in bathroom walls? Not directly in wet rooms, but in walls adjacent to bathrooms. The wool's moisture regulation helps manage moisture diffusing through the wall — but there should still be a vapour retarder towards the wet room. ### What is the difference between sheep wool and mineral wool? Sheep wool actively regulates moisture (up to 35% of its weight), has a negative CO₂ footprint (-3 to -4 kg CO₂-eq/kg vs. +1.05) and is pleasant to work with. Mineral wool is cheaper and more readily available. Insulation performance is comparable (λ 0.035-0.040 for both). ## Sources and basis - BUILD Report 2022:09 / Realdania (interval: -3 to -4, high carbon content in wool) - [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 - [Hemp Insulation](https://fremtidenstegnestue.dk/en/knowledge/materials/hampisolering): alternative-material - [Flax Insulation](https://fremtidenstegnestue.dk/en/knowledge/materials/hoer-isolering): alternative-material - [Wood Fibre Insulation](https://fremtidenstegnestue.dk/en/knowledge/materials/traefiber-isolering): alternative-material - [Cellulose Insulation](https://fremtidenstegnestue.dk/en/knowledge/materials/celluloseisolering): alternative-material - [Mineral Wool](https://fremtidenstegnestue.dk/en/knowledge/materials/mineraluld): 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/faareuld-isolering) 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.