Deck Boards

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Equation / Last modified by KurtHeckman on 2019/08/13 12:29
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pro.Deck Boards

The Deck Boards Count calculator computes the number of decking boards required for a floor or deck based on the dimension of the room or deck and the specifications of the boards.

INSTRUCTIONS: Choose your units (e.g. feet, inches, meters) and enter the following:

  • Floor Width - the width of the floor or deck
  • Floor Length - the length of the floor or deck
  • Board Size - the size of the decking boards.  This is a pull-down menu where you can select from the following standard decking board sizes:  6" x 12',  6" x 16", 150 mm x 4800mm, 146 mm x 4800 mm, 225mm x 3600mm.

The Deck Boards Count calculator computes the number of decking boards needed to achieve the specified surface area.
floor - deck boards.png                  Decking Boards  FloorJoistcount-illustration.png                  Floor Joists and Plates (end pieces). 

Construction Calculators:

The Math / Science

The most common decking board sizes in North America are:

The North American boards are actually 5.5 inches wide.  The assumption is a half inch gap between the boards.  In Europe, the most common sizes are measured in millimeters as follows:


Deck boards are either laid perpendicular to the floor or deck joists, or on a diagonal pattern.  The goal is to transfer the weight on the deck boards to the floor joist in a short distance.   Never run the deck boards parallel to the floor joists.

To compute the number of floor joists needed for a deck or floor, CLICK HERE.