Wood Wool vs Perforated Plasterboard: Which Acoustic Ceiling to Specify
On most commercial ceiling specifications the shortlist comes down to two systems: wood wool cement board, known across much of Europe as fibrolite, and perforated plasterboard. Both are mainstream, both are documented, and both will pass a building control check. They fail in completely different ways, though, and the choice usually gets made on habit rather than on how the building will actually be used. Here is the comparison as a specifier would need it.
How each one absorbs sound
Perforated plasterboard is a resonant absorber. The board itself is acoustically hard; the perforations plus the cavity and the fleece backing behind them do the work. That gives a tuned response, strong in a defined band and weaker outside it, and the performance depends heavily on getting the cavity depth and backing right on site.
Wood wool is a porous absorber. The open, woven fibre structure converts sound energy into heat across a broad range, with no tuning required. A 25 mm panel reaches an alpha w of roughly 0.60 to 0.65 depending on specification and mounting, which is solid across the whole speech band rather than excellent in one octave and poor either side.
The practical difference: plasterboard can be engineered to a target curve, wood wool is forgiving. If your acoustic consultant has modelled the room and will supervise the install, perforated board can be tuned precisely. If the ceiling will be built by a general contractor working from a drawing, wood wool gets closer to the intended result with less that can go wrong.
Impact and damage
This is where the two diverge most. Plasterboard is gypsum: a ball, a ladder or a moved scaffold tower will punch through it, and the repair is a patch that never quite matches. Wood wool is cement bonded, so it takes the hit. It can be drilled, screwed into and knocked without crumbling.
For sports halls, school corridors, changing rooms and anywhere the ceiling is within reach of people or equipment, this alone decides it. For a boardroom ceiling four metres up, it does not matter at all.
Moisture
Standard plasterboard softens and sags in sustained humidity, and moisture-resistant grades add cost. Wood wool cement board handles humidity swings without changing shape, which is why it has been the default in European swimming halls for decades. In a dry office neither is at risk; in a pool hall, wellness suite or unheated space the choice makes itself.
Installation and site reality
- Plasterboard: more trades, more steps. Board, tape, fill, sand, decorate. The finish is only as good as the plasterer, and a poor joint shows under raking light forever.
- Wood wool: panels arrive finished from the factory and are screwed to battens or a grid. No wet trades, no drying time, no decoration stage. What leaves the factory is what the client sees.
- Programme: removing the decoration stage from a ceiling can pull days out of a fit-out sequence, which often matters more than the panel price.
Fire and documentation
Both systems can be specified to demanding fire requirements, and both come with the paperwork a public building will ask for. Sonablock carries B-s1,d0 to EN 13501-1 with CE marking under EN 13168. Plasterboard systems are typically A2-s1,d0, which is a step better on reaction to fire and is the reason plasterboard still wins on some escape routes and high-rise projects where A2 is mandated.
If your specification has a hard A2 requirement, that is a genuine and decisive advantage for plasterboard. Be honest about whether the requirement is real or inherited from a template.
Appearance
Perforated plasterboard reads as a flat painted ceiling with a regular pattern of holes. It is neutral and recedes, which is exactly what some designers want.
Wood wool reads as texture. The woven fibre surface is visible and tactile, and in Natural it looks like a material rather than a finish. In White or Light Grey it behaves more like a conventional ceiling while keeping the grain. It is a design decision, not a technical one, and it is the reason wood wool has moved from sports halls into restaurants, offices and homes.
Cost
Panel for panel, perforated plasterboard is usually cheaper. Installed, the gap narrows or reverses, because wood wool removes the taping, filling and decorating stages and the labour that goes with them. Over a building lifetime the difference widens further, since wood wool tolerates knocks that would mean a plasterboard repair, and it can be repainted by spray without losing absorption.
Compare installed cost and expected repair frequency, not the panel line on a quote.
Which to specify
- Choose wood wool for sports halls, schools, swimming pools, workshops, corridors, restaurants and any ceiling that will be hit, will get damp, or is meant to be seen as a material.
- Choose perforated plasterboard where A2 reaction to fire is mandated, where the design calls for a flat neutral ceiling, or where an acoustic consultant is tuning the room to a specific curve and will supervise the build.
- Consider both in mixed schemes. Plasterboard in the quiet office core, wood wool in the sports hall and circulation, is a common and sensible split.
Working through a ceiling specification? Browse the Sonablock wood wool collection for thicknesses, fibre grades and finishes, or send us the room schedule and we will estimate coverage and pallet quantities for the whole project.
