insulit Bi+20

All in one: thermal and acoustic insulation 29 dB

The all in one underlay for screeds: thermal and acoustic insulation

insulit Bi+20 is a new acoustic AND thermal underlay exclusively designed for an installation under screeds. This underlay has been designed not only to limit the transmission of impact noise between the floors of a building, but also to provide thermal insulation under the floorings. The insulit Bi+20 underlay has to be laid under a ± 8 cm thick floating screed .

A single layer is enough to meet the acoustic and thermal insulation requirements between the floors of a building !

The Bi+20 underlay benefits from thermal and acoustic reports after tests have been carried out following the criterias of the latest applicable norms.


  • All in one : thermal and acoustic insulation
  • Light and flexible, quick and easy to install
  • Thermal foam-based adhesive included to seal off the overlaps from the screed
  • Physically crosslinked polyolefin with closed micro cells
  • Low dynamic stiffness
  • BBRI & Eco-scan – 2015 reports = guaranteed good results



Physically reticulated polyolefin and a polyester acoustic felt


≥23 mm (EN 823)


Grey (foam) / anthracit (felt)

 Impact noise insulation:

Δ Lw = 29 dB (EN ISO 717-2:2013 – EN ISO 10140-3/2010)

Dynamic stiffness:

st ≤ 7 MN/m³ (EN 29052-1)

Tear resistance:

43 – 46 N (EN 12310-1)


≤ 5% under 2 kPa

Thermal resistance:

Rd = 0,65 (m²·K)/W (EN 823:2013)


20 m x 1 m = 20 m²


± 700 g/m² (14 kg per roll)


Junction is made with an included kraft tape

Datasheet insullit Bi+20 Read online Download