For thermal insulation, Knauf Thermasoft natura combines biosourced fibers & recycled fibers
Batirama.com 24/01/20220Thermal insulation based on biological and recycled materials represents only 8% of the French insulation market, ie around 20 Mm² per year, but is growing by 15% per year.
Insulation based on materials of plant or animal origin is nothing new. As of January 24, 2022, on the website of Acermi (Association for the CERTification of Insulating Materials), there are insulations based on bulk cellulose (17), hemp, flax, bulk cotton ( 5), wood wool (25), composite wood wool (64), wood fibers (18), expanded cork (5), various materials of vegetable or animal origin (6) and fibers from recycling.
Fibers of animal, plant or recycled origin
These 6 certificates on the Acermi site include: Biofib'Trio from Cavac Biomaterials with a λ = 0.038 W/(mK), PAVATEXTIL P and PVATEXTIL R from Pavatex and their λ = 0.039 W/(mK ), COTONWOOL FLEX 25 from Buitex with λ = 0.037 W/(mK), VEGETAL from BUITEX and its λ = 0.038 W/(mK), Métisse RT – Coton Pro P/R from Relais Métisse and its λ = 0.039 W/(mK), as well as the new Knauf Thermasoft Natura.
This new insulation is certified by Acermi with a λ = 0.038 W/(mK). It is available in semi-flexible panels of 32 different thicknesses from 45 to 200 mm, in steps of 5 mm. This gives thermal resistances of 1.15 to 5.25 m².K/W.
Linen, cotton, jute
Knauf presented this new product to the trade press on January 20. The company intends it for both renovation and new construction, but only in ITI (Interior Thermal Insulation).
Knauf Thermasoft natura is made of both flax fibers (25%), cotton fibers (50%) and jute fibers (25%). ©PP
Flax fibers come from the part of flax that is not valued by the textile industry. These are by-products from industry, resulting from the transformation of flax grown in France, Belgium or the Netherlands.
The cotton is collected in Europe from clean textile scraps that do not require washing or decontamination. Jute comes from the recycling of food transport bags (coffee, etc.) collected in Europe.
The fibers are joined together by a two-component polyester thermofusible binder. The product is made in France near Lyon in an exclusive partnership with Buitex.
Thermal and environmental performance
The Knauf Thermasoft natura displays a λ = 0.038 W/(mK), certified by Acermi. It will be the subject of a technical opinion which is not yet available on the CSTB website. At the end of 2022, it will benefit from an FDES, an acoustic test report and one or more fire test reports.
Knauf indicates that it offers a density of 40 kg/m3. This gives it, according to the first tests to be confirmed, a phase shift of 6 to 10 hours for a thickness of 200 mm. As the Thermasoft natura FDES is not yet available, by taking the DED (Default Environmental Data) of the closest product from the INIES site, i.e. "Thermal and acoustic insulation for walls (ITI) and cotton fiber partitions », we find 1.15 kgCO2eq/m² for R ≤ 2.5 m².K/W and 2.31 kgCO2eq/m² for 2.5 < R ≤ 5 m².K/W.
Knauf intends Thermasoft natura only for ITI: in counter-partitions, dividing partitions, under crawling in the roof, on the ground in lost attics, etc. The company points out that from a thickness of 145 mm, laid in a double layer, Thermasoft natura meets the MaPrimeRenov' requirements in the existing system. ©PP
In new construction, this product will be more intended for filling the coffers of the walls of timber frame constructions.
The product is recycled indefinitely: it is deposited, it is defibered and new insulation is made from the recovered fibres. ©PP
Easy installation in renovation
Thermasoft natura is packaged in packs containing 3 to 8 panels of 1250 x 600 mm (0.75 m²), depending on their thickness from 45 to 200 mm. Depending on its thickness, a panel weighs from 1.35 to 6 kg. A pallet carries 8 packages. A full truck carries 22 pallets, i.e. 176 packages.
Packaging in rolls is under consideration. On installation, the first tests carried out by Knauf on real construction sites show that installers, both professionals and individuals, praise the softness of the product and its ease of cutting.
In renovation, the length of 1250 mm makes it possible to cover the standard height of a wall or a partition with two panels. As Knauf points out, all scraps are reusable.
The Knauf Thermasoft natura will be available from March 2022, both at professional wholesalers and in large DIY stores. For professionals, it will be the subject of a major launch at the Batimat 2022 show next November.
With Thermasoft natura, Knauf is targeting 1.5 to 2% of the French market for biosourced thermal insulation.
Source: batirama.com / Pascal Poggi
