Case studies

Acoustic insulation · Central Europe · 2024

European acoustic-panel manufacturer

The bio-based panel matched NRC 0.75 across the target band, passed the customer's reaction-to-fire and VOC protocols, and reduced cradle-to-gate carbon by approximately 60% versus the incumbent foam core.

NRC
0.75 (matched)
Carbon vs incumbent
−60% cradle-to-gate
Density
220 kg/m³
Pilot to series
11 weeks

Challenge

Replace a petroleum-based foam core with a bio-based alternative without losing measured NRC performance across the 250 Hz – 4 kHz target band.

Approach

We took the customer's existing NRC curve and pressing parameters and worked back to a granulometry distribution and binder loading that matched the absorption profile. Three pilot batches were pressed at the customer's line before locking in a calibrated 1.5 – 4 mm granulate at 220 kg/m³.

Outcome

The bio-based panel matched NRC 0.75 across the target band, passed the customer's reaction-to-fire and VOC protocols, and reduced cradle-to-gate carbon by approximately 60% versus the incumbent foam core.

The customer's product line had been built around a polyurethane-foam acoustic core for over a decade. The performance was known, the supplier was reliable, and the spec sheet was settled. What changed was the market: their downstream specifiers — architects, contract designers, project managers — began asking for documented embodied carbon and bio-based content. The PU core could no longer answer those questions.

Our brief was specific: match the NRC curve, do not change the panel's external dimensions or pressing cycle, and produce documentation strong enough to defend in a tender. We started with three trial granulometries, pressed in their factory under their parameters, and measured the resulting absorption coefficient in a calibrated reverberation chamber.

The winning formulation used a 1.5–4 mm graded granulate at 220 kg/m³ with their existing natural-elastomer binder system. NRC measured at 0.75 across the target band — within measurement tolerance of the foam baseline. Reaction to fire stayed at the required class without any added retardant chemistry, and the EPD we provided closed out the embodied-carbon question.

The line transitioned from pilot to series in eleven weeks, and the panel is now their default acoustic specification.