RT Time Measurement & Calculation

From 1st. July 2015, the Revised Building Regulation TGD Section E incorporates reasonable Reverberation Time in common areas of multi occupancy areas;


TGD Section E2 States –

“The common internal part of a building which provides direct access to a dwelling shall be designed and constructed so as to limit reverberation in the common part to a level that is reasonable”.

Definition for this Part E3

“In this Part – Reverberation means the persistence of sound in a space after a sound source has been stopped”.

Building Regulations Amendment Section E – makes reference to 2 Methods of Reverberation Time Control;

Method A is specifically used for Entrance Halls, Corridors, Hallways and Stairwells.

Method A is purely based on square area of suitable absorptive material being applied within the above listed locations, relative to the total square area surface of the floor plan area. Class C absorber or better to I.S.E.N. ISO 11654:1997

Method B is intended only for Corridors, Hallways and Entrance Halls as it is not suited to stairwells.

Method B is based on a more scientific approach, which calculates the amount of absorptive material and type to be applied, based on the existing internal surfaces of the floors, walls and ceiling within that space. The material required in this instance may be selected by it’s suitability to provide the required absorption;

Material Selection based on –

Entrance Halls 0.2M2 total absorption area per cubic metre of the volume.

Corridors & Hallways 0.25M2 total absorption area per cubic metre of the volume.

For more information on Reverberation Time Requirements in your development contact us?

We can advise on and calculate out your requirements, also carrying out reverberation time validation testing subsequent to installation on site.