- From the animal to the insulation, the path of the sectors:
- Insulating plants for the habitat, presentation of the stars of the family:
- Good thermal insulation performance of plant-based insulation:
- Application methods and uses of plant-based insulators:
There are many insulators of plant origin, most directly from the plant culture and others a little further from their origins because passed through the recycling stage. In order to be profitable, these insulators must first and foremost be produced in relatively large quantities, which is particularly the case with one of the best-known plant insulators: hemp. The general enthusiasm for natural products in recent years has had the effect of diversifying supply and lowering prices somewhat. Two good reasons to learn a little more about them.
From the animal to the insulation, the path of the sectors:
Insulating plants for the habitat, presentation of the stars of the family:
What makes a plant a good candidate for the design of insulation is the nature of its fibers and its intrinsic properties. But at the risk of disappointing some, it is rare to find on the market today 100% natural finished products. Indeed, many are added to their composition for reasons of stability of synthetic binders (hemp, cork and coconut fibers), polyester fibers (flax and cotton wool) or natural or non-fire treatment products, insects, rodents or fungi. The set still has a more acceptable ecological balance, especially compared to other materials used in the field of insulation.
For this article on the main insulators of vegetable origin, we will focus more specifically on hemp, goat, coconut fiber, cork, kenaf, cotton wool, flax and cellulose wadding. Of these eight plant insulators, only one, cellulose wadding necessarily comes from the recycling stream, more precisely that of paper with the recycling of newspapers and new cuts of printing. Two others, cork and cotton wool, can come either from the plant directly or be recycled. Most often for cotton wool, there is a mixture of the two, with a positive effect on the price and an additional ecological interest, because the cultivation of the cotton if it is not biological can be very polluting with a use massive pesticides and very high water consumption.
Good thermal insulation performance of plant-based insulation:
Insulants of plant origin have nothing to envy to other insulators and are no less effective. On the contrary, they generally display good thermal insulation performance. As for their phonic abilities, they are good to excellent (kenaf and coconut fibers in panels). It is therefore necessary to make a precise point of your expectations to stop your choice.
In some cases the properties of different materials can even be combined. Staying in the field of pure insulation, it can be sandwich panels composed of a layer of cork inside and two layers of coconut fiber (from the shell of the coconut). Or, of a mixed material the corkoco which is a mixture of coconut fibers and cork. By coming out slightly insulating strictly speaking, it may also be question of composite materials such as insulating plaster to the chenille (from the heart of the stem of hemp), lightened mortars made with the incorporation of granules of cork or building element with insulating virtues based on lime and kenaf (plant cousin of cotton and the same family as hemp).
From the point of view of hygrometry regulation, the use of some of these plant-based insulators can also be beneficial. Linen, kenaf and cellulose wadding have this characteristic that they regulate the ambient humidity by absorbing it and then restoring it when necessary. It is a very healthy natural process that allows the walls to breathe.
Application methods and uses of plant-based insulators:
Insulants of plant origin are available in many forms and can be used for multiple purposes. Hemp, flax, kenaf, cottonseed, cork and coconut fibers are rather general insulators in the sense that they can be used for all common insulating applications. For wall insulation, roofs and floors.
Hemp is sold in the form of rolls with vapor barrier, flax and kenaf in panels and rolls (with bumper or vapor barrier), coir and cork in rolls, panels and bulk. Cotton wool can also be in the form of fine felts and is then intended for the acoustic insulation of screed or floating floor. Note that flax is subject to settlement when used in vertical insulation.
More specific, the chèvenotte is mainly used in bulk to fill building voids by insufflation or to fill attics lost. Cellulose wadding is available in panels or granules for spreading in the attic or for filling floors. Nevertheless, it requires during its handling the setting of protection (gloves, glasses, mask) and a high technical know-how which makes that its implementation is reserved for the pros.