Abstract: This invention relates to a wall system comprising a building wall with an insulating layer, said building wall being the facade wall of a building or an inner wall, said insulating layer comprising insulation panels each insulation panel having first and second substantially parallel major surfaces. The second major surface is facing the building wall, and the insulation panel has at least three, preferably four, minor surfaces, where a slit is made in a minor surface and extending substantially parallel with the major surfaces. The insulation panel is positioned between at least two profiles, each profile having a base portion substantially parallel with and in contact with a part of one minor edge surface of the insulation panel and a flange portion substantially parallel with the major surfaces of the insulation panel and extending into said slit in the minor surface of the insulation panel.