Who Are We?

Design Acoustics Ltd was established by Tony Windner (BArch) in Tauranga 2003. Tony has over 14 years experience as an acoustic consultant in New Zealand, the USA and the UK.

Peter Horne (BEng) recently returned from the United States to establish Design Acoustics Auckland Ltd. He has over 10 years experience as an acoustic consultant in New Zealand and the USA.

Sound Isolation - reducing sound transmission between spaces

Nobody likes listening to a neighbour's stereo at 2 am. Sound transmission can be either airborne (e.g. speech, music) or structure-borne (e.g. footfall noise from an apartment above). Sound isolation is important to ensure speech privacy, for example between offices and meeting rooms. It is also necessary to minimise noise transmission between neighbours in apartments, hotels, etc.

Airborne sound transmission is commonly rated using the Speech Transmission Class (STC) method. The Impact Insulation Class (IIC) method is used for structure-borne sound transmission. Higher STC and IIC numbers mean better sound isolation. In New Zealand, minimum legal requirements apply between residential dwellings that share common walls, floors etc. The Building Code requires that walls and floors between adjacent apartments be designed with STC ratings of not less than 55, and the floors with IIC ratings of not less than 55. On some projects, higher ratings will be appropriate. Governmental agencies are becoming more aware of the importance of acoustical amenity and more stringent in enforcing sound isolation requirements. Good acoustical design at an early stage can avoid expensive remedial treatment.

Design Acoustics will set appropriate acoustical criteria and specify materials and details of walls, floors, ceilings, windows and doors. As part of the design team, we like to be involved at all design stages.

Design Acoustics © 2005

Contact us at:



Design Acoustics Ltd
Tony Windner
PO Box 13-467
Tauranga
tel 07 578 9016
fax 07 578 9017
mob 0274 173 700
tony@designacoustics.co.nz




Design Acoustics Auckland Ltd
Peter Horne
PO Box 96-150
Balmoral, Auckland 1003
tel 09 631 5331
fax 09 631 5335
mob 027 306 8525
peter@designacoustics.co.nz