Thermafleece UltraWool

Thermafleece UltraWool is a high density ultraefficient insulation rich in British sheep’s wool and is the ideal choice if you are looking for maximum thermal performance when space is at a premium.

With a density of 31 kg/m3 Thermafleece UltraWool also helps provide exceptional acoustic insulation performance in wall, floor and roof systems.

Research shows that using 75% wool in combination with recycled fibres outperforms alternative products with a higher percentage of wool. Our wool rich blend ensures you get the full benefit of sheep’s wool with enhanced performance, durability and sustainability.

Like all Thermafleece products, it is long-lasting, safe to handle and contributes to a healthier indoor environment by regulating moisture and absorbing harmful airborne substances in the home.

Why Insulate with Thermafleece UltraWool?

Insulating a property will significantly reduce the
amount of energy lost from the building envelope,
reducing energy consumption and carbon dioxide
released to the atmosphere.

High Performance

With a Thermal Conductivity of 0.035 W/mK,
Thermafleece UltraWool is the best performing natural
fibre-based insulation on the market.

Cost Effective

Energy savings from using Thermafleece UltraWool
mean it can pay for itself in a few years.

Long Lasting

Thermafleece UltraWool contains a lofting agent to
maintain durability, fibre stability and structural
integrity.

Sustainable

Thermafleece UltraWool can reduce CO2 emissions by
many tonnes over the lifetime of use. Wool also fixes
carbon dioxide helping reduce greenhouse gas levels.

Safe

Thermafleece UltraWool is safe to handle and can be
recycled or safely disposed of at the end of its life.

Specifications

Performance
• Thermal Conductivity: 0.035 Wm-1K-1
• Water Absorption (@100% RH): 30% w/w
• Specific Heat Capacity: 1800 Jkg-1K-1
• Mould Resistance: CUAP 2002-01-25: Pass
• Moth/Beetle Proofing: ISO 3998: Pass
• Vapour Resistivity: 9 MN·s·g-1m-1
• BS 5803-4, Flammability & Smoulder Resistance:
Pass
• EN11925-2, Reaction to Fire: Pass
• Fire Classification: EuroClass E
• Recoverability and thickness, EN 823: Pass
• Dimensional stability to EN 1604: Pass

Standards
• Manufactured to ISO 9001

Environmental
• GWP (A1-A3) total: 0.11 kgCO2e R1
• Recycled Content: 20%
• Recyclable: Yes
• EPD registration no. S-P-04468
• EPD valid to 31/10/26

Sizes
• Thicknesses – 50, 70 & 90 mm
• Widths – 390 & 590 mm
• Slab Length – 1200 mm

Installation and Handling

Thermafleece UltraWool is non-hazardous and can be
handled without protective clothing, although we
recommend you wear PPE in spaces such as lofts.

Protect the insulation from prolonged exposure to
sunlight when unpacked and avoid wetting, store
under cover and clear of the ground.

If the insulation gets wet during storage or as a result
of flooding in service, remove the affected insulation
and replace with new.

When installed in walls and floors, spaces filled with
UltraWool should be considered as concealed voids for
the purposes of fire risk and cavity barriers installed
as appropriate. Thermafleece UltraWool is not
suitable for use as a cavity barrier