An insulating material selected from the group consisting of filling materials for duvets, pillows, mattresses, quilts, sleeping bags, ski and winter wear and sports wear, comprising a first surface and a second surface, said first surface, when in use, being in contact with a first zone having a first temperature and a first absolute humidity, and said second surface, when in use, being in contact with a second zone having a second temperature which is lower than the first temperature and having a second absolute humidity which may be different from said first absolute humidity, said material comprising a first layer of a non-hygroscopic fibre material and a second layer of a hygroscopic fibre material, said first layer being located adjacent said first zone and said second layer being located adjacent said second zone, wherein said first layer comprises a fibre material selected from the group consisting of Polyester fibre, Polypropylene fibre, Polyamide fibre, Polyacrylonitrile fibre, Polylactic acid fibre, Polyethylene fibre and mixtures thereof and wherein said second layer comprises a fibre material selected from the group consisting of cotton, ramie, Viscose fibre, Modal fibre, Lyocell fibre, linen, hemp, Kapok, and mixtures thereof, characterized in that said first and said second layer are made of a nonwoven material with a density of from 5 to 125 kg/m 3, wherein the portion y of the thickness of said second layer related to the total thickness of the material fulfils the following criteria: - if the insulating material is selected from the group consisting of filling materials for duvets, pillows, mattresses and quilts, the portion y of the thickness of said second layer related to the total thickness of the material is 20% or more, preferably 20% to 50% - if the insulating material is selected from the group consisting of sleeping bags, the portion y of the thickness of said second layer related to the total thickness of the material is 40% or more, preferably 50% to 90% - if the insulating material is selected from the group consisting of ski and winter wear, especially winter coats, winter trousers, anoraks, winter jackets and high altitude climbing wear, the portion y of the thickness of said second layer related to the total thickness of the material is 60% or more, preferably 75% to 85% and - if the insulating material is selected from the group consisting of sports wear, the portion y of the thickness of said second layer related to the total thickness of the material is 70% or more, preferably 80% to 95%. - if the insulating material is selected from the group consisting of filling materials for duvets, pillows, mattresses and quilts, the portion y of the thickness of said second layer related to the total thickness of the material is 20% or more, preferably 20% to 50% - if the insulating material is selected from the group consisting of sleeping bags, the portion y of the thickness of said second layer related to the total thickness of the material is 40% or more, preferably 50% to 90% - if the insulating material is selected from the group consisting of ski and winter wear, especially winter coats, winter trousers, anoraks, winter jackets and high altitude climbing wear, the portion y of the thickness of said second layer related to the total thickness of the material is 60% or more, preferably 75% to 85% and - if the insulating material is selected from the group consisting of sports wear, the portion y of the thickness of said second layer related to the total thickness of the material is 70% or more, preferably 80% to 95%.