Automotive acoustic insulation

Automotive acoustic insulation is a set of PU foam components distributed throughout the vehicle to reduce noise and vibration, improving acoustic comfort inside the cabin. Main application locations are: firewall (partition between engine and cabin) with high-absorption acoustic foam, carpet underlay (foam below floor carpet), internal ceilings (headliner with laminated foam), door panels (foams in cavities), motor hood liner (internal hood lining) and various strategic damping points.

Automotive acoustic foam is not the same used in other applications. It is specifically formulated for maximum sound energy absorption at frequencies relevant to the vehicle interior (typically 500 Hz to 4,000 Hz), combined with low VOC emissions (vehicles are closed environments), heat resistance (near the engine) and durability throughout the vehicle's life. Densities range from 15 to 60 kg/m³ depending on function (absorption vs. damping vs. structural).

With the transition to electric vehicles, NVH requirements have changed significantly. EVs have silent motors but expose noises previously masked (tire rolling noise, wind, auxiliary systems). This increased demand for more sophisticated acoustic insulation — paradoxically, an electric vehicle needs more insulation than a combustion one to achieve similar perception of silence.