Thermafleece CosyWool Slab


British sheeps wool insulation for general applications within the building envelope

Suitable for use in a number of applications including roof, wall and floor systems.

Made in Britain from 75% British sheeps wool and 25% recycled polyester.

CosyWool slabs are denser than the rolls allowing for a tighter friction fit in walls and roofs.

Higher thermal mass helps buffer heat to reduce summertime overheating.

Allows a healthy moisture balance helping protect building fabric and health.

Can be safely handled without gloves or protective clothing.

Thicknesses and Availability:

This Cosywool slab range includes the following readily available product thicknesses: 50mm, 75mm, 100mm and 140mm.

Product options


Availability Indicators

Thermafleece CosyWool is sent direct to site from the manufacturer and is subject to the Thermafleece Insulation & Membranes shipping charge.

Reasonable stock levels are held with delivery lead times being around 4-5 working days. Larger orders can take a little longer ... up to 5-10 working days.

Thermafleece reserves the right to change stocked products - while we will do all we can to keep on top of changes, availability and lead times my vary.

  • Generally 1 to 3 working days for delivery
  • Generally 1 to 5 working days for delivery
  • Generally 5 to 10 working days for delivery
  • Special request or made to order item, allow extended lead times. Minimum order levels may apply.
  • Please call to check availability and approximate lead times

Delivery charges will be calculated at check-out. Please visit our Ordering From Us page for further details on minimum order levels and delivery charges. If you have any queries, please do not hesitate to contact me.

Product Application

General application insulating slabs

Thermafleece natural sheeps wool slabs, CosyWool, is suitable for use in roofs, walls and floors throughout the building.

Product Make-up

Core: Thermafleece CosyWool slab is manufactured by combining British sheeps wool (75%) and recycled polyester and binders (25%) before being compressed and cut into dense slabs.

Product Properties

Thickness50mm to 140mm 
Slab Length1.2m 
Slab Width0.39m and 0.59m 

Product Performance

Thermal Conductivity0.038 W/m·K 
Nominal Densityapprox. 22 kg/m³ 
Water Absorption30% w/w@100% RH
Mould ResistancePassCUAP 2002-01-25
Moth/Beetle ProofingPassISO 3998
Vapour Resistance> 9 MNs/gm 

Product Variants

ProductThicknessThermal Resistancekg/m²
CosyWool slab 50mm50mm1.32 m²K/W1.09 kg/m²
CosyWool slab 75mm75mm1.97 m²K/W1.63 kg/m²
CosyWool slab 100mm100mm2.63 m²K/W2.19 kg/m²
CosyWool slab 140mm140mm3.95 m²K/W3.08 kg/m²

Standards & Approval

Thermafleece CosyWool slab is manufactured in accordance with quality management system ISO 9001. All products must be installed in accordance with guidance issued by Thermafleece.

Where building regulation approval is required, you should take advice from your local building control authority and the building designer.

  • GWP (A1-A3): 1.63 kgCO2e
  • GWP (A1-A3) inc. biogenic carbon: 0.59 kgCO2e
  • Recycled Content: 20%
  • Recyclable: Yes

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