AS NZS 2785:2020 pdf free.Suspended ceilings一Design and installation.
2.1 Design
2.1.1 Aim
The aim of the design for the ceiling is to provide a ceiling system that satisfies the ultimate and serviceability limit states, while simultaneously satisfying other objectives such as aesthetics, economy and ease of construction.
2.1.2 Requirements
The ceiling system, including its connections and abutments to the structure, shall sustain all reasonably expected design actions.
NOTE 1 Design actions should be determined by referring to the applicable procedures specified in the Building Code relevant to the locality of the construction.
Unless specified otherwise:
(a) In Australia, the Importance Level of the ceiling shall not be less than that of the building or structure.
(b) In New Zealand, the Design Working Life shall not be less than that of the building or structure. NOTE 2 Refer to the New Zealand Building Code (NZBC) for durability requirements.
The service life of the ceiling can be different to the Design Working Life of the structure to which it is fitted, and unless otherwise stated, can be taken to be the warranty period.
NOTE 3 The Building Importance Level (Australia) and Design Working Life (New Zealand) of a structure is used to determine the design actions for the ceiling. Designers of ceilings should ascertain the specific design parameters for the structure from the designer of the structure.
2.1.3 General design considerations
The design process shall consider all aspects of the ceiling systems, including the capacity of the primary structure to provide the necessary support to the ceiling and the function of the building.
The design of suspended ceilings, including assessment of wind and seismic actions, should be undertaken by a competent person with experience in ceiling design for all actions. If a supplier’s generic seismic and/or wind design guide is used, it should be submitted with the tender showing how it conforms with the project requirements.
The design of the ceiling shall ensure all items interacting with the ceiling do not compromise the ceiling design.
The ceiling system design specification shall be verified as being able to resist seismic and wind actions by the provision of specific test data. For seismic actions, the design shall include details and locations of any bracing, fixed and free joints, seismic clips to join secondary framing if necessary, together with all fasteners that will meet the requirements for seismic design.
The ceiling system layout shall be designed such that the primary rails or main runners are orientated perpendicular to the primary structural elements (i.e. roof purlins in the case of steel roofs).AS NZS 2785 pdf download.