When planning your new deck, accurate measurements are crucial to avoid delays, overspending, or shortages in materials. One of the most common questions DIYers and contractors alike ask is:
“How do I convert square feet into linear feet to figure out how many deck boards I need?”
In this post, we’ll walk you through how to make that conversion, why it matters, and even offer you a free calculator tool to make the process easy.
Why Convert Square Feet to Linear Feet?
Decking is typically sold by the linear foot, not by the square foot. However, when you’re planning a deck, you’re often working with square footage — the total area of the deck surface.
To bridge that gap, you need to convert your deck’s square footage into linear footage based on the width of your decking boards. This will tell you how many total linear feet of decking material to order.
How the Conversion Works
To convert square feet to linear feet, use this simple formula:
Linear Feet = Total Square Feet ÷ (Board Width in Inches ÷ 12)
Example:
Let’s say your deck is 200 sq ft and you’re using 6-inch wide decking boards:
- Convert board width to feet: 6″ ÷ 12 = 0.5 ft
- Divide square footage by board width in feet:
200 sq ft ÷ 0.5 ft = 400 linear feet
That means you’ll need approximately 400 linear feet of decking to cover your deck.
Linear Foot Calculator
Try our built-in calculator! Just plug in your deck’s total square footage and choose width of your decking boards in inches:
Square Feet to Linear Feet Calculator
Don’t Forget Waste and Cuts
Even with exact measurements, it’s strongly recommended to order an extra 10-15% to account for:
- Off-cuts and trimming
- Mistakes in cuts
- Damaged boards
- Future repairs
So, in our 400 linear feet example, you should order:
400 linear feet × 1.10 = 440 linear feet
Ordering a little extra up front can save you time, shipping costs, and frustration later.
Final Tips Before Ordering
- Measure your deck carefully — double check!
- Know your board width (actual, not nominal).
- Decide on your deck board direction (horizontal, diagonal, etc.), as this can affect the total material needed.
- Consider spacing between boards (usually 1/8″ to 1/4″).
- Always round up when in doubt.
Build Smarter, Not Harder
Accurate planning is the first step to a smooth decking project. By converting your deck’s square footage into linear footage correctly — and accounting for waste — you ensure you’re getting exactly what you need the first time.