Basic Bearer & Joists Calculations The following two slides will help you understand the calculation process for Bearer & Joist Calculations First look at the information provided, then simply click your mouse to bring in each point. Created by M. S. Martin October 2007

Formula: Number of Bearers = Width of Building+ 1 Bearer Spacings Click your mouse to reveal each step in the calculation. Allow for bearers to run the long way of the building. Width of Building+ 1 Bearer Spacings = = 4 in total Refer to the sketch & keep clicking your mouse to see how this works Your timber order will have to indicate orderable lengths, and bearers must join over a pier, so Order for this job in 3.6m lengths, multiples of 1.8m (pier spacings – see picture & click mouse again Final order = 3.6m 100 x 75 HWD Below is a basic single room dwelling as an example for these bearer & joist calculations Spec: –100 x 75 HWD 1.8m centres –100 x 50 HWD centres = 4 Bearers

Formula: Number of Joists = ( Length of Room + 1 ) + double joists Spacing of Joist Click your mouse to reveal each step in the calculation. Allow for Joists to run the shortest way of the building ( Length of Room + 1 ) + double joists Spacing of Joist ( ) + 2 (note we deduct wall frame width) ( ) + 2 = = 19 Joists Refer to the sketch & keep clicking your mouse to see how this works Below is a basic single room dwelling as an example for these bearer & joist calculations Spec: –100 x 75 HWD 1.8m centres –100 x 50 HWD centres –100 x 50 Oregon wall frame = = 19 Joists Your total timber order will be 5.400m 100 x 75 HWD