Abstract: In order to be able to consolidate mineral fibers without binder, such as in particular glass wool into a needle-felt by needle-punching, an agent as a needling aid which comprises a thixotropizing additive having a relatively low flow viscosity during needling and thus allows to effectively support the needling process, is added to the mineral fibers. At rest, this thixotropizing additive however has an extremely high viscosity, whereby the needle-punched felt obtains good strength. In particular, for needling rock wool, suppler textile fibers are moreover added which contribute to improved mutual interlocking of the fibers, in particular in the case of mineral fibers such as basalt fibers, which can only with difficulty be interlocked by needling.

Abstract: By combining two measures, namely by using rock wool fibers with a particularly low fiber thickness, and by adding an avivage agent with an unusually high viscosity, it is possible to needle a rock wool felt, without adding any other fibers, to produce a needle felt with high strength and good bendability. If the needle felt is subsequently relaxed with heat treatment, and the avivage agent is also expelled during this treatment, the needle felt is then available as a pure rock wool needle felt, free of any organic additives.

Abstract: From a mineral fibre strip supplied in roll form, portions (L) are cut off, the length of which corresponds to the width of a rafter area between rafters plus an oversize designed to produce a clamping effect. Formed in this way, the mineral fibre panels are so inserted into the rafter area that the lateral edges of the mineral fibre strip form the top edge and the bottom edge of the panels. In this way, it is possible to achieve virtually completely wastage-free roof insulation even when the distances between the roof rafters vary considerably, and it is possible to work with material of one uniform and considerable width which is supplied in the form of rolls. By reason of the considerable width of the mineral fibre strip, insulation of one rafter area over its entire length requires only a few mineral fibre panels, with few joints being produced.