Glass wool is obtained by heating to melt a mixture of glass and sand, which is subsequently converted into fibers and cut, yielding rolls, panels or flakes. Glass wool in rolls and panels has very good acoustic characteristics, but should be protected from water, and thus it is not suitable for walls in contact with the ground and for inverted roofs.

On the other hand, glass wool is suitable for the insulation of every other element of the building envelope. Glass wool in roll form has a high ability to adapt to the surfaces that it is going to insulate. In addition, glass wool allows going around any discontinuities present (pipes, edges, projections), ensuring a good seal from a thermal and acoustic point of view. Available in rolls or rigid and semi-rigid panels, enveloped, with or without coating paper.