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Thermal and acoustic flexible wood fibre wool insulation – SteicoFLEX
SteicoFLEX flexible wood fibre wool insulation batts are:-
- high density flexible wood fibre wool (with <7% polyester), great for thermal and acoustic insulation.
- a simple way to keep your home cool in the summer and warm in the winter.
- perfect for insulating areas where keeping timbers dry is critical.
- quick to instal and do not slump over time.
- highly insulating with a conductivity of 0.036 W/mK.
Prices: from £25.43 + Vat per pack
Thermal and acoustic flexible wood fibre wool insulation – SteicoFLEX
SteicoFLEX flexible wood fibre wool insulation batts are:-
- high density flexible wood fibre wool (with <7% polyester), great for thermal and acoustic insulation.
- a simple way to keep your home cool in the summer and warm in the winter.
- perfect for insulating areas where keeping timbers dry is critical.
- quick to instal and do not slump over time.
- highly insulating with a conductivity of 0.036 W/mK.
Prices: from £25.43 + VAT per pack
Close-ups.
Take a closer look at this product with these additional images.
Image description: This is how the SteicoFlex batts are packed and will arrive.

Image description: Just so you know, this is what the SteicoFlex material looks like up close!

“The best insulation for use within any timber roof, wall, or floor. It fills all voids and doesn’t slump meaning it continues to performs as it should indefinitely” – Chris Brookman
Product overview.
Where is it used?
- In all timber structures, such as floors, walls and roofs.
- In internal partitions or suspended floors as sound insulation.
- Within historic timber frames where keeping the moisture content low is critical.
- Inside recording studios or other sound insulated structures.
How is it used?
- SteicoFLEX flexible wood fibre wool is simply pressed in between timbers or laid flat on ceilings.
- It is designed to be fitted between timbers at 600mm or 400mm centres but if it does need to be cut in any significant quantity then an ‘Alligator saw’ is the best tool for this.
- It should be cut 5-10mm wider than the void into which it is being fitted so as a snug fit without voids is achieved.
- SteicoFLEX is not suitable for cavity wall insulation or use in a masonry cavity.
Technical Details
How much will you need?
- Each batt is 1220mm long, 575mm wide or 0.7m2. 50mm, 80mm, 100mm and 140mm thicknesses are also available in 385mm widths, see the sizes/quantities tab for more information.
What is their thermal conductivity?
- The thermal conductivity of the SteicoFlex 038 is 0.038 W/mK and the density is around 50kg/m³. The thermal conductivity of the SteicoFlex 036 is 0.036 W/mK and the density is around 60kg/m³.
Product Downloads
Product overview.
Where is it used?
- In all timber structures, such as floors, walls and roofs.
- In internal partitions or suspended floors as sound insulation.
- Within historic timber frames where keeping the moisture content low is critical.
- Inside recording studios or other sound insulated structures.
How is it used?
- SteicoFLEX flexible wood fibre wool is simply pressed in between timbers or laid flat on ceilings.
- It is designed to be fitted between timbers at 600mm or 400mm centres but if it does need to be cut in any significant quantity then an ‘Alligator saw’ is the best tool for this.
- It should be cut 5-10mm wider than the void into which it is being fitted so as a snug fit without voids is achieved.
- SteicoFLEX is not suitable for cavity wall insulation or use in a masonry cavity.
How much will you need?
- Each batt is 1220mm long, 575mm wide or 0.7m2. 50mm, 80mm, 100mm and 140mm thicknesses are also available in 385mm widths, see the sizes/quantities tab for more information.
What is their thermal conductivity?
- The thermal conductivity of the SteicoFlex 038 is 0.038 W/mK and the density is around 50kg/m³. The thermal conductivity of the SteicoFlex 036 is 0.036 W/mK and the density is around 60kg/m³.
Material in action.
Here you can see the flexible wood fibre insulation being installed into a roof, under some of the UdiTOP wood fibre sarking boards. The SteicoFlex was installed in showery weather and did get wet from time to time. Whilst this isn’t what we’d recommend, the Flex dries very fast ensures that the timber structure dried out quickly too.
Prices & Shipping
Here you will find pricing and shipping estimates. To get a fixed quote, please call our technical team on 01392 861763 or get in touch via the form below.
The costs per pack of SteicoFlex are as below with a discount of 10% on full pallets. Prices do not include VAT or delivery.
Thickness [mm] | Batts per pack [pcs] | Batt dimensions [cm] | Coverage per pack [sqm] | Packs per pallet [pcs] | Pallet dimensions [cm] [LxWxH] |
Cost – single pack | Cost – pack on full pallets |
---|---|---|---|---|---|---|---|
25 | 1 | 1190 x 57.5 | 0.7015 | 184 | 122 x 122 x 250 | £3.33 | £3.00 |
40 | 10 | 1190 x 57.5 | 6.842 | 10 | 122 X 122 X 250 | £45.65 | £41.08 |
50 | 9 | 1190 x 57.5 | 6.15825 | 8 | 122 x 122 x 250 | £51.14 | £46.03 |
60 | 8 | 1190 x 57.5 | 5.474 | 8 | 122 x 122 x 250 | £52.57 | £47.32 |
80 | 6 | 1190 x 57.5 | 4.1055 | 8 | 122 x 122 x 250 | £51.71 | £46.54 |
100 | 4 | 1190 x 57.5 | 2.737 | 10 | 122 x 122 x 250 | £43.14 | £38.83 |
120 | 4 | 1190 x 57.5 | 2.737 | 8 | 122 x 122 x 250 | £51.68 | £46.52 |
140 | 4 | 1190 x 57.5 | 2.737 | 6 | 122 x 122 x 250 | £61.35 | £55.21 |
160 | 3 | 1190 x 57.5 | 2.1045 | 8 | 122 x 122 x 250 | POA | POA |
180 | 3 | 1220 x 57.5 | 2.1045 | 6 | 122 x 122 x 250 | POA | POA |
200 | 2 | 1190 x 57.5 | 1.403 | 10 | 122 x 122 x 250 | POA | POA |
220 | 2 | 1190 x 57.5 | 1.403 | 8 | 122 x 122 x 250 | POA | POA |
240 | 2 | 1190 x 57.5 | 1.403 | 8 | 122 x 122 x 250 | POA | POA |
50 | 9 | 1190 x 37.5 | 4.01625 | 12 | 122 x 122 x 250 | £33.49 | £30.14 |
80 | 6 | 1190 x 37.5 | 2.6755 | 12 | 122 x 122 x 250 | £33.86 | £30.48 |
100 | 4 | 1190 x 37.5 | 1.785 | 15 | 122 x 122 x 250 | £28.26 | £25.43 |
140 | 4 | 1190 x 37.5 | 1.785 | 9 | 122 x 122 x 250 | £40.23 | £36.21 |
Carriage is typically calculated at £70 + VAT per pallet and all orders will be sent on a pallet. However, we cannot always send full pallets as they exceed the maximum height for some transport networks. Please contact us to discuss the best way to deliver in your area.
This price does vary if delivery is required to remote locations. If you require only a few boards we may be able to get slightly cheaper shipping so please contact us for a more accurate price.
Request an estimate.
In summary, if you are looking for more than just a builders’ merchant, we might be the guys to talk to.
Request an estimate.
In summary, if you are looking for more than just a builders’ merchant, we might be the guys to talk to.
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