Tutorial: How To Calculate The Number Of Wood Required For Decking

Friday, 1 September 2017

Tutorial: How To Calculate The Number Of Wood Required For Decking

Well, i know you must have seen the other tutorial on how to calculate the number of bamboo sticks required to deck a building and would now want to know the number of planks required for the same building. 

Well, You are on Building contractor secrets and so all the secrets will be exposed at no cost for you.

Now We Will Talk On How To Calculate The number Of Planks Required for Decking.

Planks are usually dimension 1" by 12 (1 inch thick, 12" Wide). You would also bear in mind that aside from the 1 by 12 planks, metallic boards, tubery could also be used but those are quite expensive you know, so lets use 1 by 12 planks here.

Planks are required for the construction of Casing or formwork which would serve as a container for the decking. It serves as a seat for the decking.

Size Of 1 by 12.
Planks are usually 12ft or 3.6 meters long and 12 inches or 1 foot wide. This simply means that the surface area of a plank is 1.08m2.

Now Assuming we are working on the same rectangular building with dimensions 29m by 13m, the surface area would be 29 x 13 = 377m2

Now to get the number of planks required, we divide the surace area of the building by the surface area of a plank.

Therefore we would be having 377/1.08 = 350 lengths of 1 by 12 planks

We also need planks that would go round the wall to serve as support for the 1 by 12 used.
To know the number of these, we first assume the total length of the building to be 275m and since we need these planks on both faces, we simply multiply 275 by 2 and that gives us 550m

Now we divide the total length, 550m by the length of a plank, 3.6m and this gives us 153 planks

Please Understand that this does not incluse the ones needed for the staircase.

Now the total plank required would be 350 + 153 and that gives us 503 planks in total.

Now We also need 2" by 3" to serve as supports to the board along with the bamboo.

How Many 2" by 3" is required for  decking?

2”by3” wood also has to run across the lines of the bamboo studs to support the decking table too.

Assuming the 2 by 3 wood goes crosssectionally under the table along the same path with the bamboo, multiply 13m by 48=624m, divide that by 3.6 =173pcs of 2” by 3”.

For other bracing works on site, is advisable you add half of the sum to the sum above i.e (173/2)+173=260 pcs of 2" by 3"

Please also remember to buy a full role of binding wire, bag of nails (As prescribed by the forman or carpenter). You are going to pay for labour too.


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  2. Informative and educative !!!