Form · Sizes pending
Animal-Derived — indicative fig. O·02
Fire Self-extingu… Self-extingu…Embodied carbon Data pending Per-m² sourceCompressive Very low (non-load-bearing)kPa StructuralDesign life 50yr
Natural sheep wool fiber insulation with thermal conductivity 0.033-0.040 W/mK, natural hygroscopic moisture regulation (up to 30% absorption without R-value loss), self-extinguishing fire properties (ignition 560-600 degC), and carbon sequestration (1.8 kg CO2 stored per kg wool).
01 Physical
Density 10-47kg/m3
Specific gravity 1.30-1.35 (fiber); 0.01-0.05 (batt)
Porosity 90-97%
Water absorption Up to 30-33% (without losing insulation performance)%
Hardness N/A (soft flexible fiber)Shore
UV resistance Low (not relevant — concealed application)
Chemical resistance Good
pH tolerance 3-10pH
02 Mechanical
Tensile strength 120-180 (individual fiber)MPa
Compressive strength Very low (non-load-bearing)kPa
Flexural strength N/A (flexible fiber material)MPa
Impact resistance N/A (soft compressible material)J/m
Creep resistance Good (maintains loft and form over 50+ years)
03 Thermal
Thermal conductivity 0.033-0.040W/mK
Specific heat 1300-1700J/kgK
Thermal expansion Negligiblemm/mK
04 Compliance & Fire First question
Combustibility class Self-extinguishing (Class A ASTM E84, with borax treatment)
Fire resistance level Assembly dependent (wool contributes through self-extinguishing behaviour)minutes
Ignition temp 560-600degC
Flame spread index <25 (Class A, ASTM E84)FSI
Smoke dev. index 25-75SDI
Heat release rate 30-80kW/m2
05 Sustainability & Health
Embodied carbon 0.8-1.5 (production) offset by 1.8 kg CO2/kg sequestrationkg CO2-eq/m2
Carbon footprint 2-8 (production, before sequestration credit)kg CO2-eq/kg
Embodied energy 10-30MJ/kg
Water footprint 500-2000 (farming dependent)L/kg
Recyclability 85-100%
Recycled content 0-100 (product dependent, typically 75-85% wool)%
Renewable content 75-100%
Circular score 8.5/10
VOC emissions <5 (wool absorbs VOCs rather than emitting them)ug/m3
Toxicity rating Very Low (Declare Red List Free available)
LEED contribution 5-9points
06 Durability · Cost · Logistics
Expected lifespan 50+years
Maintenance interval None requiredyears
Warranty period 15-25 (lifetime available from some manufacturers)years
Material cost (range) 15-60 (R-value dependent)AUD/m2
Material cost (per unit) 12-50 (volume and R-value dependent)AUD/m2
Lead time 7-70 (source dependent)days
Lifecycle cost 25-80AUD/m2
Annual maintenance 0AUD/m2/year
Market availability Moderate — specialist supply, growing availability
07 Assessment
Advantages
- Exceptional hygroscopic moisture management — absorbs 30% weight without losing R-value
- Thermal conductivity 0.033-0.040 W/mK (comparable to or better than mineral wool)
- Auto-ignition temperature 560-600 degC — twice that of wood, self-extinguishing
- Carbon sequestration: 1 kg wool stores 1.8 kg CO2 permanently
- Non-irritant — safe to handle without protective equipment (no itching/fibres)
- Naturally antimicrobial, mould-resistant, and pest-resistant (with borax treatment)
- Excellent acoustic absorption — wool absorbs up to 55% of noise
- 50+ year service life without settling or degradation
- Australian wool supports rural economies (55% of world wool production)
- 100% biodegradable and compostable at end of life
Constraints
- Approximately 4x cost of fiberglass insulation — significant price premium
- Limited Australian manufacturing (Mountain Made is primary local producer)
- 40% of raw wool lost during manufacturing processing
- Moth attraction if untreated — borax treatment essential
- Higher embodied carbon than hemp or cotton insulation (sheep farming emissions)
- Variable density and quality between manufacturers
- Limited bulk supply for large commercial projects
- Some products contain 15-25% synthetic polyester binder (not 100% natural)
08 Applications
A1 Wall cavity insulation (timber and steel frame) Friction-fit thermal insulation batts for standard wall cavity construction
A2 Roof and ceiling insulation Thermal insulation batts or rolls between rafters and ceiling joists
A3 Floor insulation (suspended floors) Insulation batts between floor joists in suspended timber floor construction
A4 Acoustic insulation (internal walls) High-density wool batts for acoustic isolation between rooms and tenancies
A5 Green building and Passive House construction Natural insulation for high-performance building envelopes with breathability requirements
A6 Renovation and retrofit projects DIY-friendly natural insulation for residential upgrades and energy retrofits
A7 Commercial and residential applications General-purpose thermal and acoustic insulation for all building types
A8 Heritage building restoration Breathable natural insulation compatible with heritage masonry and timber construction
09 Sources & Standards
Sources pending — citations for this material are not yet recorded. Verify all figures against manufacturer data and current standards before specifying.