General requirements

075312 Soffits nailed to supports

This section covers chipboard, plywood, hard board & soft board ceiling panels nailed to timber battens. Ceiling panels shall be nailed to sawn timber complying with the requirement of Specification 07422. Nails shall be punched and stopped. The sizes, patterns and spacing of battens shall be as indicated in drawings. In the instance of details not being given, the minimum sizes of battens shall be 40x50mm and the maximum spacing 600mm center to center in both direction.

The battens shall be fixed to truss or rafters in 40x50mm sawn timber suspenders that may also be used to adjust level. In the instance of the truss spacing not being close enough to keep the ceiling battens level, timber or post back supports nailed or tied to the truss shall be provided as necessary.
Ceiling soffit panels’ edges shall be finished straight or chamfered as shown in drawings or schedules. Where ceiling panels edges are finished straight, the joints shall be covered with milled timber and molded lists not less than 30mm wide. The cover moulds shall follow strict and uniform pattern even if they are not to cover joints.
The joints of ceiling to wall shall be covered with molded corner lists of width not less than 50mm.
The gap to be left between chamfered panels shall be as detailed in drawings or where not shown not less than 10mm.
Unless specified as not needed, the joint between chamfered panels and walls shall be covered with molded corner lists of width not less than 50mm.
Ceiling panels less than 8mm in thickness shall not be chamfered.