Home > Companies > Custom Audio Designs Ltd > Foamed Polyethylene Under-Screed Resilient Layer IsoScreed Foam

When used in conjunction with the appropriate floor materials it meets approved document E requirements and has the added bonus of water resistance. It can also protect the mineral wool during screed laying.

It significantly reduces impact noise and vibration under a floor screed as well as providing a degree of airborne and thermal insulation. It can also be used on top of a concrete floor especially if the floor has failed an impact sound test.


  • Significant reduction in impact noise and vibration.
  • Easy to cut.
  • Lightweight.
  • Water resistant.
  • Prevents growth of fungi, bacteria and mildew.
  • Does not significantly raise the floor level.
  • Flexible.
  • Does not rot or decay, even when exposed to high temperatures and humidity.


  • Concrete impact reduction under screed.
  • Timber floors.
  • Building Regulations (E&W) Approved Document E compliant.

Standard product features


Inert, physically cross-linked closed cell polyolefin foam sheet. Fine cell structure with two process skins.

Roll size:

30 x 0.925 m.




0.17 kg/m².


5 mm.


33 kg/m³.

Dynamic stiffness:

14 MN/m³.

Fire rating (full system):

60 minutes.

Acoustic performance:

29–71 Rw dB, refer to manufacturers' data sheets.

NBS Specification

NBS Create logo
This product is associated with the following NBS Create clause:
45-45-70/437 Resilient layer insulation

Product specification

An important note about specifying



Custom Audio Designs Ltd


+44 (0)1730 269572

Product reference

Foamed Polyethylene Under-Screed Resilient Layer IsoScreed Foam

Manufacturer details

5 Ridgeway Office Park,
Bedford Road,
Hampshire, GU32 3QF
Tel +44 (0)1730 269572
Fax +44 (0)1730 265846
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