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Tables 30/31 — Ridge & Intermediate Beams

AS 1684.2
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Inputs

Timber Grade
Span Type
Roof & Ceiling Mass (kg/m²)
Roof Load Width — RLW (mm)

Maximum Beam Span & Overhang

AS 1684.2 Table 30 — Single Span — Wind classification N1/N2

Size (D×B mm)Max Span (mm)Max Overhang (mm)
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Design Reference

Figure 7.29 — Ridge and intermediate beams design parameters
Figure 7.29 — Ridge and intermediate beams (AS 1684.2:2021)

Notes (AS 1684.2 Tables 30 & 31):

i) Maximum spans are based on the support of roof or roof plus ceiling mass for a cathedral roof.

ii) Allowable overhangs are based on no birdsmouth or notching. Overhangs shall not exceed 50% of actual backspan.

iii) Minimum bearing length = 35 mm at end supports and 70 mm at internal supports for continuous members. Some cells in the standard carry subscript values indicating additional bearing length required at those supports — refer to AS 1684.2 Table 30 or 31 directly for those entries.

iv) Multiple members nailed together as per Clause 2.3.

v) Wind classification N1/N2 only.