Felt Acoustic Panels for Offices, Gyms & Nightclubs: Function + Aesthetics

An office floor in Bengaluru had forty felt panels on the wall behind reception and nothing anywhere else. The client had bought them because a supplier said felt fixes echo, and they were disappointed. Standing in the open-plan area, you could hear a conversation four desks away well enough to follow it. The panels were doing exactly what they were rated to do. There were simply not enough of them, they were 9 mm where the room needed more, and they were on the one surface that was not causing the problem.

Felt panels are the most specified absorber in Indian commercial interiors right now, and the most commonly misapplied. They cut easily, they come in colours an architect will accept, and they install without a frame, so they get used as a finish first and an acoustic product second. Used properly they are excellent. Used as decoration with an NRC number attached, they disappoint people.

Thickness is the lever, not the colour

The one number to hold on to is this. Echsorbix PET felt runs NRC 0.30 at 9 mm and reaches NRC 0.60 at 24 mm, with 12 mm and 18 mm in between, all tested to ASTM C423. That is a straightforward relationship. More material absorbs more, particularly lower down the frequency range, because a thin porous absorber can only act on wavelengths short enough to be affected by it.

What follows from this is the decision most people get wrong. A 9 mm panel is a mid and high frequency absorber. It takes the edge off speech sibilance, keyboard clatter and the hard reflections off glass, and on a lightly reverberant room that is enough. It will not touch a bass line or the thump of a dropped weight. If the complaint in a room is low and heavy, adding more 9 mm felt will not fix it no matter how much of it you fit. Going to 18 mm or 24 mm, or leaving an air gap behind the panel, moves the useful range down.

Why an open-plan floor needs coverage, not a feature wall

Speech travels across an open floor by bouncing off the ceiling and the glass. A single treated wall removes one reflection path out of many, which is why the Bengaluru reception wall changed so little. What improves speech privacy is distributed area, placed on the surfaces the sound is hitting most often, which in almost every open-plan office means the ceiling plane and the vertical faces close to people's heads.

That leads to a different set of moves. Panels on desk-height partitions, where they intercept speech before it spreads. Panels on the glass-facing walls where the first reflection lands. Suspended absorbers over workstation clusters where a solid ceiling cannot be treated. Meeting rooms treated separately and more heavily, because they carry the confidentiality requirement. Treating the ceiling and the partitions matters more than treating any one wall, however good that wall looks in a photograph.

What changes when the room is a gym?

A gym has two problems and they need two answers. The first is reverberation, which makes music muddy and instruction hard to follow. Felt at 9 mm to 18 mm on the walls handles this well, and it survives the environment because PET does not shed fibres, does not hold sweat the way an open mineral face would, and can be cleaned.

The second problem is impact. A dropped dumbbell is structure-borne energy, and no surface absorber will stop the tenant downstairs hearing it. That is a floor build-up question, handled with BassBloc isolation under the flooring. Clients often ask for more felt when what they need is an isolated floor.

A nightclub is a different problem entirely

In a club the sound system is the point, so the goal is not a dead room. It is control of the reflections that smear the mix at high volume. Felt does the mid and high frequency work, and because the panels can be cut to shape and printed, the treatment carries the venue's identity rather than looking like a technical retrofit.

Low frequency is handled behind the finish rather than on it. BassBloc sits behind the panels where the room needs low-frequency absorption, and wooden slats are often used alongside felt for diffusion and for a more premium surface. Where the ceiling is high and open, ceiling baffles add absorbing area without covering the services.

Does the finish cost you performance?

No, and this is one of the genuine advantages of PET felt over older absorbers. The material is the finish, so there is no fabric layer to reduce the open area and no frame to build. The range exists to let the panel do design work at the same time.

• ColourMute: more than 20 solid shades, for corporate, fitness and nightlife interiors.
• Mirage PET grooves: linear grooves with a subtle three-dimensional depth, used most in workspaces.
• Canvas prints: graphic printed panels carrying logos or artwork, for branding walls and feature areas.
• Geometric screens and baffles: suspended absorbers for gyms and clubs where wall area is limited.

Where felt stops and something else has to start

Absorption and isolation are different jobs and felt only does one of them. If the noise is coming from outside the room, from a road, a plant room or the neighbouring tenancy, no amount of panelling will help, because absorption acts on sound already in the room. That is where SoundBlanket MLV goes in, at STC 30 at 2.5 mm and STC 34 at 4 mm, inside the wall build-up rather than on its face.

A full treatment on a difficult space therefore runs in three layers. MLV behind the wall to block what is arriving from outside. BassBloc behind the panels, at NRC 0.85, supplied in 20 mm and 40 mm, to absorb the low end that felt cannot reach. Felt on the visible face for echo control. Specifying the third layer without the first two is the most expensive mistake in this category.

What a Bengaluru co-working floor took

The co-working office described at the start was a glass-walled open-plan floor with poor speech privacy and no ceiling treatment. We fitted Echsorbix Mirage PET groove panels in the meeting rooms, where the privacy requirement was highest, and ColourMute felt on the open-floor partitions so speech was intercepted close to the source rather than after it had crossed the room. Reverberation fell by around 65 per cent, and the finish read as an interiors decision rather than an acoustic repair.

Where to start on your own floor plate

Decide first whether the complaint is echo inside the room or noise arriving from outside it, because that single answer decides whether felt is the right product at all. If it is echo, identify the hard surfaces doing the reflecting, then start with the ceiling plane and the vertical surfaces nearest to people, not the wall that happens to be free. Choose thickness by the frequency of the complaint rather than by budget, and remember that 9 mm and 24 mm are genuinely different products. Send us the floor plan with ceiling heights, finishes and the use of each area, and we will come back with a panel layout, thicknesses and a BOQ rather than a square metre rate.