How to calculate how much decking you need

Monday, 7 August 2017  |  Admin

One of the most asked questions of the Atlantic Timber team is "How do I calculate how much decking I'll need?"

We'll try and keep it as simple as we can:

  • Once you’ve measured the area you want to deck, the first thing you need to decide is which way you want to run the deck boards. Usually the boards run the longest side of the area, i.e. on an area 3m x 6m the deck boards would run the 6m direction.
  • The other dimension is your span, i.e. how many boards you need to cover that area.
  • Take the width of your deck board and add a 5mm gap, which is needed to allow adequate air flow under and between the boards to avoid damp building up underneath your deck and causing the boards to rot. Our most popular deck board is 120mm so this becomes 125mm with the air gap.
  • Divide your span by the width of the board (including expansion gap) so 3m is 3000mm, divided by 125mm = 24 boards. As the deck in this example is 6m long we now need to times the 24 boards by 6m to give us our total metreage of decking, which is in this case 144m.
  • You now need to decide which length of deck board is most suitable as you don’t want all of your joints to be in the same place. To minimise waste you can use the off cut from the first row to start the next row, this also gives a nice random joint pattern. In this example we would suggest a 4.2m board so you have a good off cut to start your next row. This would mean you would need 35 deck boards (144m divided by 4.2m = 34.285 boards).

The only thing left to do is order your boards from our great selection and get cracking on building your deck! 

Remember you can always give us a call on 0161 928 1696 or drop in to see us - we're always happy to help.