Engineered Wood Acoustic Performance Rating: What Architects Need to Know

If you're specifying engineered wood for a multi-family or commercial project, acoustic performance rating is one of those specs that can make or break your specification. Here's what the numbers actually mean.

The Two Metrics That Matter

For flooring and wall assemblies, there are two core acoustic ratings:

ΔLw (Impact Sound Reduction): Measured in dB. Higher number = quieter floor. Target for multi-family: ≥ 17–20 dB.
Rw (Airborne Sound Insulation): Also in dB. Higher = better. Target for party walls: ≥ 50–55 dB depending on local code.

These are lab numbers. Real-world performance depends on the full assembly — underlayment, joist type, ceiling below, and how well the contractor follows the spec.

Typical Acoustic Performance by Product Type

Product Type	ΔLw (typical)	Rw (typical)	Notes
Standard engineered wood flooring	10–14 dB	35–40 dB	Needs acoustic underlayment
Modified wood flooring + acoustic pad	18–22 dB	40–45 dB	Chambroad recommended spec
Wall panels (timber cladding)	N/A	30–38 dB	Depends on backing / cavity
Ceiling panels (timber slat)	N/A	25–35 dB	Acoustic backing improves significantly

Values are typical; actual performance depends on full assembly. Always request assembly-level test data.

The Underlayment Factor (Often Overlooked)

Here's something many specifiers miss: the acoustic performance rating of the wood panel itself is only half the story. The underlayment or acoustic pad underneath contributes 60–70% of the ΔLw value.

Chambroad supplies engineered wood panels with pre-attached acoustic backing as an option — which eliminates on-site installation variables and ensures the tested assembly matches the installed assembly.

How to Read an Acoustic Test Report

When your engineered wood acoustic performance rating supplier hands you a test report, check:

Test standard — ISO 10140 (laboratory) or ISO 16283 (field). Field numbers are what your building inspector will measure.
Assembly description — is the test for the panel alone or panel + underlayment + joist? You need the full assembly data.
Frequency range — acoustic performance isn't flat across all frequencies. Look at the 125–4000 Hz range for meaningful data.
Laboratory name — acoustics is precision work; unknown labs = questionable data.

Keep in mind: a ΔLw of 20 dB in the lab might translate to 14–16 dB in the field, depending on workmanship.

Chambroad's Acoustic Solutions

Our modified wood flooring is available with three acoustic configurations:

Standard (no acoustic pad) — suitable for single-family or commercial spaces where acoustics aren't regulated
Acoustic-backer option — 2mm cork or recycled rubber backing, ΔLw ≈ 17–19 dB
Premium pre-attached pad — 3–5mm acoustic foam, ΔLw ≈ 20–22 dB; meets most European multi-family codes

Each option comes with a test report from SGS or Intertek, so you have documentation for your building permit application.

Specifying the right engineered wood acoustic performance rating starts with knowing your target building code — not just picking the highest number on a datasheet. If you want help matching our products to your local acoustic requirements, we're here. Chambroad's technical team can provide assembly-level test data and help you document the specification for permit submission.