Acoustic Underlay for Screed Floors — Expert Guide

Written by our acoustic insulation specialist — 15+ years experience supplying soundproofing to UK homeowners, developers and contractors. About our experts.

From our acoustic insulation specialist — screed floors are common in modern flats and new builds.

Screed floors — whether sand:cement or anhydrite — are increasingly common in modern residential construction, and they are excellent substrates for acoustic underlay.

Why Screed Is Good for Acoustic Underlay

Screed provides a flat, level, and rigid substrate that maximises the performance of acoustic underlay. Unlike timber joist floors (which flex and introduce complexity), a solid screed floor allows the underlay to perform exactly as tested.

Which Underlay for Screed

Our 6mm rubber underlay (74dB) is ideal for screed floors — the rigid substrate allows full acoustic performance. For Part E compliance in new builds with screeded separating floors, our 12mm acoustic flooring system provides the full system performance required.

Anhydrite Screed — Important Note

Anhydrite (calcium sulphate) screed is common in modern new builds. It requires lightly sanding before laying acoustic underlay to open the surface and ensure adhesion of any tape. Never apply a moisture barrier over anhydrite screed before it has fully dried (typically 1mm depth per day). Contact our team for advice on anhydrite screed installations.