Mammal hair (or down feathers from birds) are the only thermal insulators which are actually produced naturally.
It should come as no surprise, then, that mankind began to use this resource at a very early stage, particularly sheep’s wool, in clothing and even to improve the thermal protection provided by the "third skin" of their dwellings.

Its curly fibre gives it a great capacity to store air and thus increases its insulating capacity.

For millennia, yurts and almost all nomadic dwellings in cold countries have been built using wool felts as a heat barrier.

In sedentary habitation, evidence of use goes back to the Middle Ages.

Since 1990, sheep’s wool has been processed on an industrial scale in Germanic countries and has become an approved building material.
The production plant for KLIMALAN products is in Germany, in Dinkelsbühl, Bavaria.

The shorn wool is first washed to remove any impurities, especially wool grease, which is secreted by the animal through its skin and has a characteristic odour. One of its functions is to repel parasites.
The wool is then treated using a natural moth repellent insecticide made from permethrin, Mitin. Mitin is stable and produces no emissions after application; it is classed as non-dangerous for human use by the distributors of environmentally-friendly materials.
It is then carded and textured to produce the various high-quality products which make up the range.

It is a strange but proven fact that sheep's wool purifies the air! The protein substance in the fibres of sheep’s wool contains chains of amino acids which are capable of absorbing high concentrations of molecules of harmful substances and unpleasant odours, such as formaldehydes and aldehydes, and of neutralising them. This procedure is called chemisorption.

A condensation reaction takes place in the formaldehyde during which the harmful methylol is transformed into a neutral methylol and permanently fixed. The harmful substances are not only absorbed, but also completely eliminated.
Aldehyde and derived substances are present in, among other products, paints, lacquers, glues, bonding agents, hot fats and disinfectants.
The reaction of formaldehyde with the chains of amino acids in the wool protein has been used very effectively for many years to sanitise buildings exposed to high concentrations of formaldehyde.


In addition to its sorptive and thermal qualities, sheep’s wool is an excellent noise insulator because it offers genuine soundproofing solutions.

Sound pollution makes life difficult in an apartment, but even in an individual home, occupants are still assaulted by noises from traffic, nearby houses or the pounding of rain or hail on the roof – unless soundproofing or acoustical insulation has been installed.

There are two main types of noise: airborne noise, coming from the outside and propagated through the air, and in-home noise that comes from inside the dwelling itself and is transmitted by floors, walls and ceilings.

Each noise is made up of waves that are partially absorbed by objects, but most of them are nonetheless perceptible to the human ear. The goal of soundproofing is to reduce these noises to a minimum. System performance can be measured by the index of sound damping (Rw), which is expressed in decibels.

Acoustical insulation follows three basic principles: the law of mass, which states that the heavier the insulating material, the better the insulation; the mass-damping-mass law, which determines the degree of noise absorption by the damping agent; and finally, the law of air-tightness, which states that where air enters, noise also filters through.

Concretely, thickness and damping quality of the soundproofing material are very important because when noise hits the first mass – the wall, for example – soundproofing material intercepts it immediately and dampens the noise before transmitting it to the second mass.

The soundproofing material thus described is made up of air filled with a particular insulator. This can correspond to different types of materials; however, natural insulators, such as KLIMALAN insulation made from lambswool, are, of course, preferable because they are ecological and by far the best performers.

Highly resistant to fire

In terms of fire protection, KLIMALAN's sheepwool insulation materials are extremely effective. When the wool is washed and its suint removed, its auto-ignition temperature is 580°. This quality makes it by far the least flammable of natural fibres. Wool is self-extinguishing, does not propagate flame and, most importantly, does not emit toxic gases. It chars and burns away but does not ignite.

In addition to its fire-resistant natural composition, the wool also receives a fire-proofing treatment primarily composed of boron salts.

Rolled sheep's wool

The wool is bound and textured to form rolls of varying formats and thicknesses which are suitable for insulation between horizontal or inclined structural elements.
The rolls are available with the wool fixed to supporting felt:
KLIMAVLIES NWL or with loose wool, without supporting felt: NWL PUR.

KLIMAVLIES NWL density range: 35 – 40 km/m³
  • flooring
  • sloping roofs
  • roof spaces
  • draught-proofing

Sheep’s wool in semi-rigid boards

The wool is bound and textured to form boards of varying formats and thicknesses which are suitable for insulation between vertical, horizontal or inclined structural elements:

  • walls with internal insulation
  • interior insulation for walls
  • exterior insulation for wall
  • sloping roofs

Bulk sheep’s wool

Sheep's wool can be used as it comes in building works as an insulation fill to be laid manually, preferably using the above procedure: KLIMALAN WOOL IN BULK.

  • flooring.
  • draught-proofing for usable roof spaces

Felted sheep's wool

Presented in the form of rolls with a non-aerated texture, the wool acts mainly as a sound insulation board (resilient layer).

Felt is suitable for use as a soundproof underlay for floating parquet flooring, in 1 and 2 metre widths and rolls of smaller widths to acoustically separate floor joists: KLIMALAN NWF 100/200 and KLIMALAN NWF IN 10/15 STRIPS

  • parquet flooring
  • floating parquet flooring
  • Floor joists

Braided wool

The fibres of the wool are braided to draught proof door and window surrounds and various openings in facades and roofs.

KLIMALAN technical data

  • Indicated thermal conductivity (lambda): 0.035 W/mK
  • Reaction to fire: German standard B2 (EN 13501-1) EURO class E. Low flammability.
  • Resistance to deformation: (EN 824) < 5 mm/m.
  • Thickness tolerance: (EN 823) < -5%; < -5mm.
  • Apparent density: (EN 1602) 35 – 40 Km/m³
  • Airflow resistance: (EN 29053) 4.4 kPas/m²
  • Water absorption: (EN 1609) < 0.92kg/m²
  • Resistance to water vapour penetration: u = 1
  • Thermal capacity: Cp 1630 J/kg*k
  • Flammability index: 5.3 CH
  • Construction material class: B2 (D)

Characteristics of KLIMALAN insulating materials

  • Easy and enjoyable to lay and manipulate.
  • Hygrometric regulator.
  • Acoustic insulation significantly superior to conventional materials.
  • Reaction to fire: low flammability, self-extinguishing, no emission of toxic vapours.
  • Not liked or consumed by rodents.
  • No emissions of VOC or other pollutants, no formaldehydes.
  • Fully recyclable.

KLIMALAN sheep’s wool has excellent hygroscopic qualities (it can absorb up to 33% of its own weight in water without reducing its insulating capacity).

If outside walls are sufficiently permeable to water vapour, it can be used without any steamproofing.

Environmental impact

  • Sheep’s wool is of course a renewable resource because it adds value to a product which is directly linked to agriculture.
  • Recycling and disposal: reusable material.
  • KLIMALAN products are fully compostable because they contain no polyester texturing.
  • In the event of fire, there are no toxic emissions.
  • It has very good sound damping qualities and effectively reduces airborne noise.