Table 4B.16: Maximum clear span of purlins supporting rafters

Table 4B.16 Maximum clear span of purlins supporting rafters (m); Roof pitch more than 15° but not more than 22.5°; Imposed load of 1.00 kN/m2; Timber strength class C16 C16 Dead Load [kN/m2 ] excluding the self weight of the purlin Size of purlin (mm): Not more than 0.50 / More than 0.50 but not more than 0.75 / More than 0.75 but not more than 1.00 Design spacing of purlins (mm): 1500, 1800, 2100, 2400, 2700, 3000 (for each dead load category) 47 x 150 through 2 x 47 x 300 sizes with corresponding maximum clear spans in metres.