Cavity filling

Loose cavity fills

Fills have to do a lot: bring a floor up to the right level, provide thermal and acoustic insulation and save energy, and ensure a comfortable environment for the building occupants. It should also not provide a home for pests, such as rodents for example. While insulating mats are complicated and invariably wasteful to cut, the amount of material required for a fill can be calculated precisely in advance and can be processed efficiently. Liapor's mineral fills are permeable, perfectly conceived construction solutions. Lightweight and easy to apply, Liapor loose fills spread into every corner to completely fill cavities and voids. Liapor can supply four different types of fill: spherical granules or mixed with crushed Liapor – both loose and in bonded form.

Loose and dry

The loose, dry Liapor fill is particularly suitable for filling cavities in multi-layered or timber beam floors. This type of fill guarantees outstanding acoustic and thermal insulation while imposing only a very low static load. In particular in the field of old building renovation, loose fills can solve numerous problems because the material provides both mechanical and chemical resistance. The granules are not attacked by either acids or alkalis.

A lightweight material with excellent thermal insulation

A heat-insulating fill for solid and timber beam floors must offer a high level of thermal insulation coupled with an excellent ability to retain heat. The fine-pored lightweight Liapor expanded clay spheres possess these characteristics combined with a high compressive strength. The thermal insulation properties, which are determined by the thermal conductivity I, are dependent on the bulk density and the grain density of the employed Liapor product. A low bulk density conferred by a lightweight Liapor product offers lower thermal conductivity λ and consequently a higher level of thermal insulation. Thus Liapor 8/16 achieves a thermal conductivity of λ = 0.089 W/(m K), while Liaporfit offers a level of λ = 0.095 W/(m K).

Granules available in many formats

Liapor's non-crushed dry fill material can be delivered in bulk by truck, by silo wagon, in "Big Bags" of 1,000 or 2,000 litres each, or in 50-litre sacks. What is more, Liapor's bulk dry fills are quick and easy to use. Once poured, Liapor is self-compacting and can be evened-off using only a levelling rod. Liapor has many applications: as a drainage fill for foundation work, as a heat-insulating fill in contact with the soil. However, the loose fill can also be used as a fill for intermediate floors, between wooden beams or for the loose filling of arched structures. When used as an overfill for piping or other installations, the Liapor material can be removed just as quickly as it was applied. Thanks to the many different properties of Liapor expanded clay and the large product portfolio available, Liapor fills are always the first choice when it comes to tailor-made floor solutions.

Selected references

Floor renovation with dual Liapor fill


Bonded Liapor fill


Heat-insulating, compression-resistant substructure