Separation layers

If you want to reduce impact sound, the screed is laid as a “floating” layer. In this construction, insulation is first of all laid on the floor followed by in most cases one or more layers of STYROPOR® insulation boards as an insulating layer, and then finally screed is poured on top of this.

However, a separation layer is needed between the insulation boards and the screed because screed could easily migrate through the abutting edges of the insulation boards and then transmit impact sound to solid structural components. Depending on the type of screed, we recommend using bitumen lining paper or PE film as the separation layer.

Bitumen lining papers

At GERA Chemie, we only use pure bitumen and recycled waste paper as the raw materials to produce bitumen lining paper.
Bitumen is a by-product in the mineral oil industry, produced as “heavy waste” in refineries when crude oil is processed to light mineral oils and fuels. Bitumen is used primarily in road building and for roofing felt; only GERA uses it for industrial papers (we are the only manufacturer of bitumen lining paper).

We impregnate the paper with bitumen using a special process – no admixtures and no white edge. The finished bitumen lining paper acts as a separation layer under conventional screed and under asphalt screed, as a protective layer in brickwork, in road building / rail construction, and to protect against corrosion, oil and damp in a number of other industrial, commercial and packaging applications.

Bitumen lining papers:
GERA Bitumen Paper B150

PE films

PE films (also called PE construction films) can be used as a general-purpose separation layer under all types of screed, the exceptions being asphalt screeds and bonded screeds.

Our PE films can be supplied unfolded in a width of 1.5 m. Wider sheets up to 4 m are available, but are folded one or more times to a width of 1 m convenient for transport.

Our standard range of PE films includes film thicknesses of 40 to 200 my (0.04 – 0.20 mm thick) in both opaque (dark) and translucent (milky) colours.
A 50 my thick transparent masking film completes our range.
We carry both “sealing materials”, which are films with max. 5% unavoidable production tolerance in the thickness of the material, and also “standard materials” with different sub-tolerances.

There are strict rules regarding the minimum thickness for use as a separation layer. Please ask about any requirements that apply.

Please refer to “Insulation sheeting” and “Edge insulation strips” for information on acoustic decoupling for floors and walls.