Earthquake forces can act in the vertical and/or horizontal direction, and these forces cause excessive damage, especially if the suspended ceiling has not been designed correctly.

USG Australasia has manufactured DONN grid seismic systems in NZ since 1969 and has invested significantly in steel engineering, testing (AS/NZ 1397 and AS/NZS 4600) and quality control (ISO 9001), and use expert seismic-consulting engineers in preparing the USG Seismic Design Guide. This guide is now available via download.

Potter Interior Systems, established in 1959, is the master distributor for USG in New Zealand, and with branches in Auckland, Wellington and Christchurch is a leading supplier of materials for the commercial wall and ceiling industries.