Rubber vs Cork Acoustic Underlay — Which Is Better?

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

The debate between rubber vs cork acoustic underlay comes up on almost every acoustic flooring project. Both materials reduce floor noise effectively, but they have different strengths, weaknesses, and ideal applications. This is the definitive comparison.

The Fundamental Difference

Both rubber and cork are resilient materials — they deform under load and spring back, dissipating mechanical energy (i.e., impact noise) rather than transmitting it. However, they achieve this through different mechanisms:

• Rubber: High density, closed-cell structure, exceptional resilience. Excellent at impact damping across a wide frequency range.
• Cork: Open-cell structure, natural air pockets absorb and scatter sound energy. Good at mid-frequency attenuation and thermal insulation.

Impact Noise Performance

In objective testing to ISO 10140-3, rubber consistently outperforms pure cork at equivalent thicknesses:

• Our 6mm Recycled Rubber: 74 dB ΔLw — industry-leading
• Our 3mm Recycled Rubber: 54 dB ΔLw
• Our Cork & Rubber Composite (3–5mm): ~55–60 dB ΔLw

Winner for impact noise: Rubber — especially our 6mm product.

Thermal Performance

Cork has naturally lower thermal conductivity than rubber. For rooms with underfloor heating, this matters — lower TOG means more heat passes through to the room.

Our Cork & Rubber Composite has a lower TOG rating than pure rubber, making it preferable for UFH installations where maintaining heat output efficiency is important.

Winner for UFH compatibility: Cork Rubber Composite

Environmental Credentials

Our rubber underlay is made from recycled rubber — post-industrial and post-consumer tyre rubber that would otherwise go to landfill. It is a genuine circular economy product.

Our cork composite uses cork harvested from the bark of cork oak trees — a renewable resource. The trees are not felled; bark is stripped every 9 years and naturally regenerates.

Both are sustainable choices. Recycled rubber wins on diverting waste streams; cork wins on natural material provenance.

Ease of Installation

Both materials cut cleanly with a sharp Stanley knife. However:

• Rubber is heavier per roll — budget extra time for handling large areas.
• Cork composite is lighter and often easier to manoeuvre in tight spaces.

Which Should You Choose?

Explore both options: Acoustic Underlay Range