Calculating Deck board for the deck

To calculate your requirements as a general rule simply multiply the area of the deck by 7,
this will give you the approx lin meters of 144mm width deck board to do the job.
For example lets say you wish to build a deck 5mt x 4mt, the area is
     5 X 4 = 20 sq m
The linear meters will be:
     20 X 7 = 140 linear meters

Always allow some extra boards for cutting and waste.

Calculating Joists for the deck

The amount of joists 100mm x 47mm required at 450mm centre is approximately,
half the total linear meters of deck board.
In the example above one would buy
     140 / 2 = 70 linear meters

Always allow a bit extra for waste and cutting

You can use our online calculator for a rough estimate of the materials needed