This is a step-by-step calculator that gives you all the options, though you don't need to feel overwhelmed as you can skip any step along the way. Those steps are simply there so you don't forget about fascia boards, edging, clips, and your subframe. You simply start by selecting your design, length, and colour, key in your length and width in metres, and go through each step based on everything we've learned you will need—skipping what you don't and adding what you do—while it works everything out for you.
4m Grooved Composite Decking Board
- Type: Grooved
- Material: Wood Fibre & HDPE Plastic
How Many 4m Grooved Boards Do You Need? Calculate Your Area
Quick Board Calculator
Just need to know how many boards your project takes? Enter your length and width to get an instant board count and cost estimate for your area.
Calculate Boards Only ↓Full Project Calculator
It's easy to overlook hidden clips, starter clips, edging trims or joists. Build your kit step-by-step and skip anything you don't need.
Build Full Project ↓Total
Select options
Quantity
Step into sleek with our 4m Grooved Composite Decking Board, a smarter choice for faster installs and a flawless finish. The extended length means fewer joins and cuts, making it quicker to lay and easier to perfect. It’s the ideal option for large projects or bold layouts where clean lines and minimal effort go hand in hand.
Reversible and lightweight, each board offers a traditional wide-groove texture on one side and narrow classic grooves on the other—two looks in one. Slip-resistant, splinter-free, and low-maintenance, these boards come in Anthracite Grey, Classic Grey, and Bold Black for timeless curb appeal that lasts through every season.
Need a different look? Explore our other full length composite decking boards to browse alternative designs and lengths for your project.
Please Note: Order Your Free Samples
We highly recommend ordering our free samples to confirm the colours before placing an order, as digital photos can vary significantly between screens.
Reversible Traditional Grooved Design
Family-Safe Surface
4m Lengths
Expert Advice for 4m Grooved Decking Boards
Want to know more? Our in-house expert, Allan, gives his take on our 4m Grooved Decking, and we’ve selected some of our best guides to help you decide if this is the right choice for you.
A Word from Our Expert, Allan:
Our 4m Grooved Decking gives you a classic, traditional finish in a longer length designed for faster installation. As part of our Home Choice collection, it offers all the recognised benefits of proven quality and great value, in a board that helps you save time on your project.
In fact, offering different board lengths is a direct result of our experience. After guiding thousands of customers, one thing became clear: the right board length is just as important as the right colour. We understood this early on and are proud to be one of the first providers in the UK to offer a wide range of lengths to suit any garden, big or small. The reason is simple: we listen.
What Are The Key Benefits of Our 4m Grooved Decking Boards
-
Faster InstallationCover more ground in less time. The extended 4m length reduces the number of cuts and boards needed, making it ideal for large areas and time-sensitive projects.
-
A Uniquely Repairable SurfaceBased on our years of experience, our grooved decking features a unique sanded surface. Unlike many other composite decks, scratches and minor stubborn stains can be effortlessly blended out, all without ever needing painting or staining.
-
Clean & Seamless FinishFewer boards and joins create a sophisticated, uninterrupted look, perfect for modern garden designs.
Specifications
-
Length
4000mm
-
Width
150mm
-
Finish
Grooved
-
Thickness
22mm
-
Available Colours:
Anthracite Grey | Grey | Black
-
Weight (per board)
Approx. 10kg
-
Material
High-Density Polyethylene & Wood Fibre Composite
-
Warranty
10-Year Residential
Calculate Your Composite Decking Boards & Project Kit
You may already know what you need or have your build planned out. In this case, our quick calculator lets you work out just the boards you need for your project—with recommended accessories populated below so you can easily add them if needed.
Area
0 m²
Required Boards:
0
Composite Joists – Size: 3m x 100mm x 50mm
C24 Timber Floor Joist 47mm x 100mm x 3.6m
Composite Posts
Timber Posts Treated 100mm x 100mm
Slim Hidden Fasteners – Decking Clips
Plastic Decking Fasteners
Ultra Composite Decking Clip
Calculate Your Decking
Calculate
Delivery Information
| Delivery Type | How Long? | Delivery Cost |
|---|---|---|
| Urgent | Estimated 1-4 Working Days | £79.99 |
| Normal* | Estimated 5 to 7 Working Days* | FREE |
| Royal Mail Standard (Small Parcels) | 3–5 Working Days | £8.00 |
| Royal Mail Standard (Large Parcels) | 3–5 Working Days | £29.95 |
| Collection | Collection from our warehouse | FREE |
| Sample Packs | 3–5 Working Days | FREE |
| *Normal | Distance Deliveries Can Exceed Estimate | FREE |
FAQ About Our 4m Grooved Decking
1 Can I install the decking myself?
Absolutely! Our grooved design is compatible with a simple hidden fastener clip system. If you’re comfortable with basic DIY tools, installation should be a breeze. The larger boards also mean you’ll enjoy a much faster installation time!
2 What’s the difference between the two sides of the board?
One side features a wide-groove texture for a modern, timber-inspired look. The reverse side has a traditional narrow-groove finish, offering superior grip and a timeless appearance.
3 Will the grooved boards fade over time?
As with all composite materials, a small amount of UV-related colour softening (around 20–30%) is natural. However, our boards are designed for long-term colour stability, especially in darker shades, such as Anthracite Grey.
4 Is grooved decking slippery when wet?
Not at all. Both sides of the board offer excellent slip resistance, making them ideal for high-traffic outdoor spaces, even after a summer downpour.
5 How many boards do I need for my space?
We recommend measuring the total area of your deck in square metres and consulting our team or using our decking calculator to get an accurate board count based on your chosen layout and spacing.
6 Why are they cheaper compared to wood grain boards?
They use less material and are engineered specifically for homeowners and residential use. Joist centres must be set at 300mm, and the thin-grooved side is recommended for the best performance on these boards.
As Seen In
