Underlay for Floor Panels and Acoustic Insulation
A well-chosen underlay for floor panels is the most effective way to soundproof a floor in a house or apartment. There are two key parameters to pay special attention to when looking for an underlay with high acoustic insulation:
- The first is RWS (reflected walking sound), which measures the noise of footstep echoes. The higher this value, the less audible the reflected sounds—such as footsteps—generated in the room where the laminate wood-based panels are installed.
- The second is impact sound insulation (IS). Unlike RWS, this refers to the sounds heard in the room below. The better the insulation, the less audible any thumping or knocking sounds. It's especially worth considering an underlay with high impact sound insulation when trying to soundproof a floor in an apartment block or attic.
Which Underlay for Panels to Choose
Durability and soundproofing are important functions of an underlay. However, when deciding which underlay to choose, you should also consider other parameters (always choose products marked with the construction B symbol), such as subfloor unevenness compensation, moisture protection, thermal resistance (very important with underfloor heating), resistance to impact, load, and compression. Below is a brief overview of the most popular types of underlays with short descriptions.
Polystyrene Underlay
Excellent acoustic insulation, compatible with underfloor heating, and great resistance to water vapor diffusion (moisture), which significantly affects the durability of floor panels. The IDEAL PROFI 2.0 underlay offers a high RWS value of ≤ 26%. It’s an excellent solution for those wondering how to soundproof a floor to ensure comfort when using new flooring. Additionally, IDEAL PROFI 2.0 is an acoustic underlay with outstanding thermal resistance, high density, and is made from 93% natural materials and polyurethane binders.
Polyethylene Foam Underlay
Its main advantage is price. Polyethylene foam underlay is relatively inexpensive compared to other types. However, it offers lower acoustic insulation and thermal resistance, so pay special attention when selecting it for rooms where soundproofing or absorbing footstep echoes is important. For comparison: while IDEAL PROFI 2.0 has RWS ≤ 26%, the PROFI PE polyethylene foam underlay has RWS ≤ 16%. The market also offers other underlays, such as those dedicated to vinyl flooring (typically 1.4 mm thick) or underlays designed for laminate flooring with enhanced water resistance up to 24h (e.g., Alu Aqua 3in1).
Cork Underlay
Unlike the types mentioned above, cork underlay is considered natural. It effectively dampens footstep sounds and the noise of items falling on the floor, and it’s suitable for use with underfloor heating. However, many floor manufacturers do not recommend this option. Another downside is the price—high-quality cork underlays from verified sources are typically expensive.
Summary: How to Soundproof a Floor?
As mentioned at the beginning, a high-quality underlay for panels (always with the B construction mark) is the foundation of how to soundproof a floor. It also ensures long-term enjoyment and full performance of your new flooring.
