The reverberation time (RT) you need depends on how the room is used. For speech-focused spaces such as classrooms, offices and meeting rooms you want a short RT so words stay clear; for music or performance you want a longer, more 'live' RT. In England, BB93 sets a maximum mid-frequency reverberation time of around 0.6 seconds for ordinary new-build teaching spaces, and BS 8233 gives good-practice guidance for other buildings. Absorbent surfaces shorten RT inside a room, but they do not block sound travelling between rooms.
What reverberation time do I need?
The reverberation time (RT) you need is set by what happens in the room, not by a single universal figure. Rooms built around the spoken word - classrooms, offices, call rooms, lecture theatres - want a short RT so that each syllable decays before the next arrives and speech stays intelligible. Spaces for music, worship or performance often want a longer, more resonant RT that adds warmth and body. Decide the primary use first, then choose a target.
Reverberation time targets by room use
As a rule of thumb, the more a room depends on clear speech, the shorter its reverberation time should be. Classrooms, meeting rooms, open-plan offices and healthcare consulting spaces all sit at the short end. Auditoria, music practice rooms and performance halls sit longer, and the ideal is genuinely use-dependent - a chamber-music room and a band rehearsal room are not the same brief.
Room size matters too. Because reverberation time rises with volume, a large sports hall will always reverberate longer than a small office for identical finishes, so bigger rooms need proportionally more absorption to hit the same target. Weigh the room's function and its volume together, then tie the target to measured absorption data rather than guesswork.
How do schools and regulated buildings set the target?
For schools in England, BB93 sets a maximum mid-frequency reverberation time - around 0.6 seconds for ordinary new-build teaching spaces, and tighter still where pupils have a hearing impairment or additional needs. Approved Document E cites BB93 as the way schools demonstrate compliance, so the target there is a regulatory limit, not a preference.
For other buildings, BS 8233 offers good-practice reverberation guidance by room type without a single universal number. Where a design has to meet a standard, the dependable route is an acoustician modelling the room against measured absorption data - panels are a tool, not automatic compliance. Our reverberation time explained guide covers the concept, and UK acoustic comfort standards gathers the relevant documents.
Does a lower reverberation time mean the room is soundproofed?
No. Reverberation time describes how long sound lingers inside a room; lowering it with sound-absorbing surfaces makes that room clearer and calmer for the people in it. It does not stop sound passing between rooms - that is sound insulation, which depends on mass and construction and is governed separately. Absorbent wood panels reduce echo and RT, but they will not stop a conversation being heard through a wall. Absorption and soundproofing solve two different problems.
How to hit your target reverberation time
RT falls as you add absorption: Sabine's equation (RT = 0.161 x V / A) shows it drops as total absorption A rises for a fixed volume V. In practice that means adding absorptive surfaces - wall panels, ceiling rafts or baffles - until the calculated RT meets your target. Estimate the quantity with our how many acoustic panels do I need guide, then sanity-check the figure in the reverberation calculator.
Frequently asked questions
What is a good reverberation time for a classroom?
In England, BB93 sets a maximum mid-frequency reverberation time of around 0.6 seconds for ordinary new-build teaching spaces, with tighter limits for pupils who have a hearing impairment or additional needs. Approved Document E treats BB93 as the compliance route, so a school design should be modelled against measured absorption data rather than assumed.
Is a shorter reverberation time always better?
Not always. Short reverberation suits speech, so classrooms, offices and meeting rooms benefit from it. Music and performance spaces usually want a longer, more 'live' RT for warmth and body, so the right target is set by the room's primary use rather than by making the room as dead as possible.
Will acoustic panels give my room the right reverberation time?
Acoustic panels add absorption, which shortens reverberation time inside a room - the more effective absorption you add for a given room volume, the shorter the RT. How close you get to a specific target depends on the panels' tested absorption and how much surface you treat, so for a regulated space an acoustician should model it against measured data.
Does lowering reverberation time reduce noise from the room next door?
No. Reverberation time is about how sound behaves inside one room, and absorbent panels only address that. Stopping noise passing between rooms is sound insulation, which relies on mass and construction, not absorption. Panels make a room sound clearer but do not soundproof it against neighbouring spaces.