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Timber framing code 2008: Floor Framing. Specification:. Timber framed construction Conventional timber framed roof Roof pitch 22.50 Roof covering steel roof decking, 10kg/m2 Eaves width 600mm Brick piers supporting bearers Bearers 150 x 75 Unseasoned Hardwood, F11
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Timber framing code 2008: Floor Framing.
Specification: • Timber framed construction • Conventional timber framed roof • Roof pitch 22.50 • Roof covering steel roof decking, 10kg/m2 • Eaves width 600mm • Brick piers supporting bearers • Bearers 150 x 75 Unseasoned Hardwood, F11 • Joists 100 x 50 Unseasoned Hardwood, F11 • Fitted timber floors Utility grade 19mm T&G Radiata Pine • Wet area flooring 19mm CSR structafloor particleboard
Remember the following information: • Type of flooring determines the MAX SPACING of floor joists • SPAN of joists determines the SPACING of bearers • SPAN of bearers determines SPACING of piers
Bearers, Clause 4.3.1 • The max span of 1600 for the floor joists will determine the max spacing of the bearers parallel to the building length. • Determine from the various tables the span for the given bearer size (150x75). • These spans determine the pier spacings
Bearers supporting load–bearing walls • RLW = Rafter span + overhang • Rafter run • = 7.470 / 2 • Rafter run= 3.735 • Rafter length = 3.735 / Cos 22.5o • Rafter length = 4.042 • Overhang =600 / Cos 22.5o • Overhang =0.649 • RLW = 4.042+0.649 = 2.670 2 • RLW = 2.7
FLW Bearers: load bearing walls • Table one of Supplement 13 • Say RLW of 4500 (2700 actual) • FLW = 1600/2 = 800 (based on max joist span) • Read max bearer span from table 1 for FLW 1200 • Allowable span for 150 x 75 = 1700
Bearers: floor loads only • Table 5, supplement 13 • FLW = ? (Based on max joist span) • FLW = 1600 • Go to Table 5 for FLW 1800 • Allowable span of bearer: 150x75 = 2100
Centreline spacing of brick piers • Supporting load bearing walls This is determined by the span of the bearer supporting load bearing walls • = span of bearer plus 230 (size of brick pier) • = 1700 + 230 • = 1930
Centreline spacing of brick piers • Supporting floor loads only This is determined by the span of the bearer supporting floor loads only. • Span of bearer plus 230 (size of brick pier) • = 2330