Lattian eristysrakenne

The invention relates to an insulation structure (1) for sound and heat insulation of floors. The insulation structure (1) comprises at least two layers made from an at least partially closed-cell foam plastic material. Of these layers, the layer that in an operation position is the upper layer (2) is substantially non-perforated, and the layer that in the operating position is the lower layer (3) is provided with apertures (4) for reducing tension and tightness of the material. This solution enables the sound insulation properties of the insulation structure to be improved.