If you’re looking to breathe new life into your garden this summer, decking is a fantastic way to make the most of your outdoor space. But before you get started, you’ll need to know how many decking boards to buy—especially if you’re planning Laying decking yourself
While the answer will depend on a variety of factors — such as the type of material and the size of the gap between each board — there’s an easy way to estimate a rough number, as our decking expert demonstrates below.
To find out how to estimate, measure your garden accurately and where to buy the best decking supplies, keep reading – we’ve covered everything you need to know.
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How many decking boards do I need?
To determine how many decking boards you will need in your garden, Jack Williams, founder JPW Fencing and Deckingrecommends using the following simple formula:
Decking width for deterioration ÷ decking board width + 5%
Alternatively, you can estimate two boards per square meter when using standard 3.6m-long, 150mm-wide decking boards, according to Alan Jeffrey, commercial director of Ultra decking.
This calculation will help you get a rough idea of how many decking boards to buy. However, you may want to talk to a professional installer for a more accurate estimate of your exact space—especially if you’re dealing with an awkward shape.
Where to buy decking supplies
Vicks Standard Treated Deck Board
This budget-friendly decking costs just £2.50 per square meter and is pressure treated to resist rot.
Get accurate measurements of your decking area with this smart laser tool, which has integrated memory for up to 10 areas.
eDecks RealGroove 3600mm Solid Composite Decking Boards
Durable, anti-slip and reversible, these composite decking boards are built to stand the test of time in your garden.
Jack Williams is the founder of JPW Fencing, a Bristol-based company specializing in landscaping services. He has over 10 years of experience working with wood and composite decking, patios, fencing, garden houses and more.
With over 40 years in product design and development, Alan Jeffrey has set out to make high-quality composite materials affordable for every UK homeowner. Since launching his first collection, he has led the way in combining durability with style, offering authentic surface textures and market-leading stability – all at a meaningful price. Today, Alan personally reviews every product, guide and resource to ensure you get lasting quality and real support.
How do I accurately measure my decking area?
Now that you know how to calculate how many decking boards you need, your next question is probably how to work out the decking area. To do that, Alan Jeffrey says to measure the length and width of the space.
If you’re building a raised deck, you’ll also need to measure how high off the ground you want it to sit. It will be supported either by posts set into the ground (for soft surfaces) or pedestals for hard surfaces such as concrete.
While it’s certainly possible to do an approximate calculation online, Alan Jeffery says that for the most accurate results, it’s best to speak to a professional decking installer who can tailor your garden.
For more expert advice on installing your dream decking, read our guide How to build a raised deck And you should choose whether Wood decking vs composite.
