Acoustic Panel Materials Compared: Foam, PET, Wool

"Just send me your best acoustic panel" is a request we can't really answer well, because the right material depends on what the room actually needs beyond absorption alone, fire performance, moisture exposure, budget, appearance, and how much low-frequency control matters. Here's how the four materials that come up most often actually compare.

Fibreglass: the performance benchmark

Fibreglass panels typically achieve the highest NRC ratings of any common material, often in the 0.90 to 1.0 range, and are the long-standing benchmark against which other materials get compared in professional studio and commercial specification. The trade-off is handling and installation: loose fibreglass requires a fabric or facing layer to be usable as a wall or ceiling panel, and some specifiers avoid it on projects where occupants might have direct contact with an unfaced product.

Mineral wool: fibreglass-level performance with built-in fire resistance

Mineral wool, rockwool-based panels sit close behind fibreglass at roughly 0.85 to 0.95 NRC, using the same basic porous-fibre absorption mechanism, but with a genuine practical advantage: mineral wool is naturally fire resistant without additional treatment, which is why it's become the default core material for commercial-grade panels where fire rating is a serious specification concern, schools, healthcare, hospitality, anywhere meeting a Euroclass B-s1,d0 baseline matters.

PET felt: the practical middle ground

PET felt panels, made from recycled polyester fibre rather than glass or mineral fibre, typically land around 0.75 to 0.85 NRC, a genuine step below fibreglass and mineral wool, but with advantages that matter for certain projects: no glass fibres or mineral particles to irritate skin or lungs during handling, a wide range of achievable colours and finishes since the material takes dye well, and generally easier, cleaner installation. It's a common choice for visible, occupied spaces like offices and public areas where appearance and handling matter as much as absolute absorption performance.

Melamine foam: budget-friendly but frequency-limited

Melamine foam covers the widest performance range of the four, from around 0.65 up to 0.95 NRC depending on thickness and how far it's mounted off the wall, foam is unusually sensitive to air gap. It's typically the most affordable option and works well for mid and high-frequency speech absorption, but it does comparatively little for low-frequency, bass-range noise, so a room with boomy, low-frequency reverberation problems needs deeper foam, a different material, or dedicated bass trapping, not just more foam of standard thickness.

How to actually choose between them

Start from the constraint that matters most for your room, not from a generic best-to-worst NRC ranking. Fire rating requirement usually points toward mineral wool. Visible, high-traffic public areas usually point toward PET felt for its finish options and cleaner handling. Recording studios and performance spaces chasing maximum absorption per unit area usually still specify fibreglass. Budget-constrained projects treating mid and high frequencies successfully use foam, provided the room's actual problem isn't low-frequency in nature.

Common questions

Is a higher NRC material always worth the extra cost? Not automatically, once a room's absorption need is met, additional NRC beyond that point delivers diminishing acoustic benefit for the extra spend.

Can these materials be combined in one room? Yes, and it's common: mineral wool or fibreglass in areas needing maximum performance or fire resistance, PET felt in visible occupied zones where appearance matters more.

Getting the right material for your space

See our guide to NRC ratings explained, or browse our acoustic solutions to compare real products against your room's actual requirements.

Related product guides: PET acoustic panels, acoustic wall panels, timber slat panels.