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  1. Residential structures (BCA Classes 1, 2, 3 and 10) and light commercial structures.
  2. Maximum Roof Pitch of 45°.
  3. Maximum Span 16m.
  4. Shape in plan view to be rectangular or near-rectangular, or a series or a combination of rectangular shapes or near-rectangular shapes, including splayed-end and boomerang-shaped buildings and the like, and projections such as bay windows.
  5. Maximum truss spacing of:
    1. 900mm; or
    2. 1200mm, for sheet metal roofs in an area of design wind speed up to N3.
  6. Maximum design gust wind speed of 74m/s wind classification C3 for ultimate limit state method in accordance with AS/NZS 1170.2 or AS4055.

Figure A1-03-01-03