Decking Calculator

A decking calculator can determine the amount of material to build a deck. It simplifies the process because the deck size, type of material, and structure elements can all be included.

Factors such as deck dimensions, load-carrying ability, choice of material, spacing of joists, beams, and decking boards are considered to determine the exact amount of material needed. Here are some Critical elements in a decking calculator include;

Deck measurement: Length and width of the deck surface. These define the total area to be covered by decking material.

Decking material: This defines what decking material shall be used, the board size, and the material required.

Board width: Influences the number of boards needed to support the decking.

Joist spacing: defines the distance between joists for the framing material to support the decking.

Waste factor:The amount of decking material wasted during the process.

An extra 10% or more is added to the total account for cutting mistakes or damages.  

Calculation Process

When designing a decking project, it is vital to determine the exact amount of materials needed, such as decking boards, fasteners, and supports. The first step in this is to get an accurate amount through material takeoff to ensure that every aspect of the project is considered to avoid overestimating or underestimating the materials. Here are some steps required for the calculation process.

Calculate the Total Area of The Deck 

The first step is to calculate the total surface area of the deck.

Example: let’s suppose you need to construct a rectangle-shaped wooden deck with the following requirements: 

• Deck dimension: 12 feet by 20 foot 
• Deck material: pressure-treated lumber 
• Board width: 6 inches 
• Joist spacing: 16 inches apart 
• Waste factor: 10% extra material for error or defects 
• Total area = length x width = 12ft x 20 ft = 240 sq ft

Calculate the Area that Each Decking Board Would Cover

Determine how much area the decking board would cover. Given the width of the board is 6 inches and the length is 20 feet, the area of one board is calculated as follows

• Area per board = 0.5 ft x 20 ft  = 1- sq ft

Calculator Number of Board Required

To find the number of boards needed to fully cover the entire deck area, divide the total deck area by the area covered by one board

• No. of board = total area/ area per board = 240 sq ft /10 sq ft = 24 board

 Waste Factor Addition

It is prudent to factor in some allowance for scrap. You will need to purchase extra material to allow for the inevitable mistakes and damaged items:

• Total board with waste factor = 24 board x 1.10 = 26.4 boards round up to 27 boards

Calculate the Number of Joists Needed

Since the joists are spaced at 6 inches, and the deck is 20 feet long, you can calculate the number of joists by dividing the length of the deck by the spacing between the joists.

• Convert the spacing into feet: 16 inches =1.33 feet.
• Number of joints = Deck length/ joist spacing =20 ft/ 1.33 ft = 15 joists

Calculate the Number of Beams and Posts

Larger decks have more structural elements, such as beams and posts. Beams are horizontal supports that support the joists, and posts are vertical supports that hold up the beams. The deck size and local building codes determine the number of beams and posts.

For example, assume for simplicity that you will need to parallel beams the length of the deck:

• You may get about four posts with supporting beams for a normal-sized deck.

Add Fasteners and Other Parts

When computing, this will be able to approximate the number of fasteners, like screws or nails, needed to hold the decking board to the joist. The numbers are based on how many boards are in the space between the boards.

Example

• Deck screw; 200–300 screws to secure one decking board
• Stairs: If your deck has stairs, the decking calculator calculates the material you need for your stair framing.

Frequently Asked Question 

Q: What Kind of Materials Does a Decking Calculator Work With?

 A decking calculator can work with numerous materials, such as pressure-treated wood, composite decking, and PVC, all of which have unique properties that can influence joist spacing and board size.

Q: What Is ‘board Width’ in A Decking Calculator?

Board width is the actual width of individual decking boards. It determines the number of boards needed to cover the total deck area. In other words, a 6-inch board has more area covered per board than a 4-inch board.

Q: How Do I Adjust the Calculations if My Board Sizes Differ from Standard?

Put the width and length of your chosen boards into your calculator for accurate results. Board sizes that you customize usually affect the total number of boards and the entire material usage of the boards.