- From the animal to the insulation, the path of the sectors:
- Sheep wool, duck feather and house insulation:
- Forms of products and places of use of insulators of animal origin:
Unlike plant-based insulators, those of animal origin are in fact very few, mainly for reasons of production and economic rationalization. So much so that only two types of insulators of animal origin are now available: sheep's wool and duck feather. Two well-known animals raised for a long time for their meat production. But what about their insulating abilities? To find out more, let's look at their design first.
From the animal to the insulation, the path of the sectors:
Of course to make an insulation of animal origin worthy of our homes, a minimum of transformation is necessary. It's not enough just to mow a sheep or to pluck a duck to put everything in bags. On the contrary, a certain number of treatments for materials against moths and molds are for example indispensable before any commercialization.
For sheep wool, there are two types of production. One by needling, entangling the fibers with a series of needles. The other by thermolysis where are added to the wool fibers of polyester or polypropylene, all worn at high temperature to offer a better resistance to wool. Of the two versions, needling is the one that produces the most dense insulation, but also the most expensive.
For the duck feather, one and the same technique is used. It is the large feathers that are used for insulation, the down and the small feathers being almost exclusively reserved for the middle of the bedding. To transform them into insulators, here too, the use of a percentage of polyester fibers is necessary and curiously a little wool of sheep (between 10% and 20%) to give it elasticity.
As for the exploitation on the territory, although both species are present, only duck feather insulation demonstrates a real valorization of the sector (slaughterhouses). Indeed, although sheep farming for food still exists in France, these wools are used very little and much of it ends up burned. The raw material is therefore imported, most often from Australia or New Zealand, which are the main sheep wool producers in the world.
Sheep wool, duck feather and house insulation:
Of comparable performance, sheep wool and duck feather both provide good thermal and acoustic insulation. Sheep wool nevertheless, although it provides a high level of comfort in winter, is a little less advantageous in summer because of its low thermal inertia.
In terms of fire behavior, sheep's wool is naturally very flammable. An advantage that is not found in the duck feather that ignites easily. This is the reason why duck feather insulation must be placed with a siding.
Settlement phenomena in vertical insulation may occur for these two types of insulation. For the duck feather, only in case the insulation has not been properly fixed. Of the two, it is without a doubt that sheep's wool has the poorest stability, which explains why it should not be subjected to compression constraints in its laying technique.
Forms of products and places of use of insulators of animal origin:
Sheep wool is sold in the form of felts, rolls and bulk. The felts used primarily for the acoustic use of floors and the bulk to fill the building voids or attics lost. More versatile, sheep wool rolls are used for attics, roofs and caisson filling. They can also be placed in vertical walls, but must be stapled for this purpose.
On the other hand, given its sensitivity to moisture, sheep wool is not recommended for the insulation of rooms and therefore the bathroom. To avoid also, its use for the insulation of the external walls of the house and a floor in contact with the ground of the ground floor.
The duck feather comes in rolls or panels. It can be used for the insulation of reported ceilings, floating floors and more generally in all wood frames as well as in the attic. For the attic however, if you have a chimney, the duck feather insulation must absolutely not touch the duct of it for obvious safety reasons. A space of at least 20 cm must be filled with another insulator with flammable properties. Also, avoid contact with heat sources such as built-in spotlights.