For floor constructions above existing floorboards, it is important that the floor is even, without significant differences in level. Loose Fill is excellently suited for levelling uneven floors. Loose Fill is manufactured from the natural raw material shale, in a special thermal process. Loose Fill does not contain any chemical additives and is therefore a high quality, environmentally-friendly material with outstanding grain strength. Old floorboards must first be provided with an appropriate trickle protection.