From an environmental sustainability standpoint, a well-executed insulation system is highly important in terms of energy saving and reducing CO2 emissions. It is therefore advisable to choose natural thermal insulants that possess very specific characteristics: protection from cold in winter and heat in summer, acoustic insulation, moisture diffusion to prevent condensation, durability over time, and resistance to fire, mould, fungi and pests.

However, not all natural materials used as thermal insulants are ecological — it all depends on the production process they have undergone. The lower the energy required to process them, the more we can truly consider them eco-sustainable. There are nonetheless several materials of plant or animal origin that lend themselves well to the thermal and acoustic insulation of our homes. Here are the most effective ones used in green building.

Coconut fibres for home insulation

Following Indian tradition, coconut fibre insulant is obtained by taking the fibrous part of the coconut, immersing it in water and mud for six months and leaving it to dry in the sun. Thanks to this maceration process, the coconut fibre is stripped of its perishable organic parts, making it durable over time. During the pressing stage, which takes place in Europe, the resulting compound can be pressed together with other substances such as natural rubber, which makes it water-repellent and smooth to the touch.

Sheep's wool

This material of animal origin has biological characteristics that give it a particular climate-regulating capacity against both cold and heat. Being water-repellent, it is also able to absorb up to 33 per cent of moisture, reducing the risk of condensation that would damage the building.

It is, moreover, a renewable and recyclable raw material, derived from wool waste from the textile industry, subjected to specific, low-impact treatments that transform it into reliable insulating panels that also protect against potential pest attacks.

Cellulose fibres

Cellulose fibre comes from recycled newspaper treated with boron salts, which make it resistant to fire and insects. Among its recognised properties are insulation from cold and absorption of heat; its use allows pleasant temperatures to be maintained indoors even in summer.

Cork

When not treated with adhesives, cork is a valid biocompatible and breathable insulant characterised by a zero degradation factor. In essence, it is impervious to insects and rodents and does not rot. It is precisely its longevity that makes it a cost-effective material for home insulation, as it allows for considerable energy savings over the years.

Wood fibres

This is a completely ecological material: it is obtained from sawmill wood waste that is ground and subsequently bonded with lignin, the resin naturally produced by wood. Its strength lies in its capacity to insulate the home from noise and, above all, from heat, which is retained for a longer period than with traditional insulants.

Hemp fibres

Among hemp's numerous uses is that of insulating panels used in building construction. To produce them, the plant's stems are chipped, combined with a natural adhesive such as potato starch, and finally compacted at high temperatures. Thanks to its highly wear-resistant fibre and its shiv (the woody part contained inside the plant) with excellent absorbent properties, hemp presents itself as a highly effective natural insulant: lightweight, breathable, resistant to mould, insects and fire, biocompatible and recyclable.

Insulating a home using systems that involve the use of natural resources is very important for the environment and for people. Starting with the built environment to reduce electricity waste and CO2 emissions is therefore essential for creating more liveable and more sustainable communities.