The short answer
In the UK, composite decking typically costs around £150 to £250 per square metre supplied and fitted, with the rate driven mainly by the grade of board. Uncapped boards sit at the lower end, while capped (co-extruded) boards with a protective shell cost more and resist fading and staining better. Hollow boards are cheaper than solid ones, which are heavier and feel more like timber. Supply-only board prices are lower, often around £40 to £80 per m2, because they exclude the subframe, groundworks and labour. The frame and groundworks are similar to a timber deck, so the per-metre premium over softwood is mostly the boards themselves, plus slightly closer joist spacing on some systems.
Composite usually carries the highest per-metre rate of the mainstream materials, but there is a real spread within it. Knowing the grade — capped or uncapped, hollow or solid — is the key to reading a composite quote.
Composite decking per m2 at a glance
- Typical supply-and-fit rangeAround £150–£250 per m2
- Supply-only (boards alone)Around £40–£80 per m2
- Cheaper gradeUncapped / hollow boards
- Premium gradeCapped / solid boards
- Premium over softwoodMostly the boards themselves
What moves the composite rate
Composite is not a single product, and the per-metre rate moves with the board you choose. The two big variables are whether the board is capped and whether it is hollow or solid:
- Uncapped: solid composite throughout, cheaper, but more prone to fading and staining over time.
- Capped (co-extruded): a tough polymer shell bonded around the core resists fading, scratching and stains, sitting at the higher end of the range.
- Hollow: uses less material and weighs less, so it tends to be cheaper.
- Solid: heavier, feels more like timber underfoot, stronger, and usually dearer.
The figures below are indicative supply-and-fit ranges for guidance only.
| Composite grade | Indicative cost per m2 (supplied and fitted) | Notes |
|---|---|---|
| Uncapped | Around £140–£190 | Lower cost, more fade and stain over time |
| Capped (hollow) | Around £160–£220 | Protective shell, lighter board |
| Capped (solid) | Around £190–£250 | Heaviest, most timber-like, premium feel |
Indicative UK figures for guidance only; obtain itemised quotes for your site. Sources: Checkatrade and MyJobQuote 2026 composite decking cost guides.
What the rate covers beyond the boards
As with any deck, a composite per-metre rate covers far more than the boards when it is a supply-and-fit figure. The main lines are:
- Groundworks: clearing and levelling, with a membrane and gravel beneath.
- Subframe: the joists and bearers. Composite boards are heavier than timber and some systems specify closer joist centres, which can add a little frame material.
- Boards: the largest material cost, plus cutting and wastage.
- Hidden fixings: many composite systems use clips that sit in a groove on the board edge for a fastener-free surface, adding a little over plain screwing.
- Trims and finishing: matching fascia, corner trims, steps and balustrade.
- Labour: setting out, framing and laying.
Because the subframe and groundworks are close to a timber deck, the per-metre premium over softwood is largely the boards and, sometimes, the tighter joist spacing rather than a wholly different build.
Why the per-metre rate eases on larger decks
The composite per-metre figure is an average across the whole job, not a fixed price for every metre, so it responds to the size and shape of the deck just as timber does. Several practical points shape where in the range a quote lands:
- Area: larger decks spread the fixed costs of set-up, foundations and edge trims over more metres, so the rate tends to ease. A small deck carries a higher rate because those costs barely reduce.
- Shape: a plain rectangle is the most economical. Curves, borders and multiple levels add cutting and waste, which matters more with composite because offcuts cannot be re-treated and reused as freely as timber.
- Trims and capping: a fully finished edge with matching fascia and corner trims adds cost over a plain board run.
- Region and access: labour rates and the ease of moving the heavier boards into the garden both affect the figure.
So while composite sits at the upper end of decking rates, the figure for your own deck depends on its size, shape and finish. The clearest quote breaks out the boards, frame, trims and labour, so you can see the per-metre rate is buying a complete, properly framed deck rather than boards alone.
Frequently asked questions
Why does composite decking cost more per square metre than timber?
Composite boards are manufactured from recycled wood fibres and plastic, which costs more to produce than sawing softwood, and capped boards add a protective outer layer that raises the price further. The subframe and groundworks are similar to timber, so most of the per-metre premium is the boards themselves.
Is uncapped composite decking much cheaper per metre?
Uncapped composite is cheaper per metre than capped, because it lacks the bonded outer shell. The trade-off is that uncapped boards can fade more and are more prone to staining over time. Capped boards cost more up front but hold their colour and resist marks better, which many owners find worth the difference.
Does the composite per-metre rate include the frame?
A supply-and-fit rate should include the subframe, groundworks and labour, not just the boards. A supply-only board price, often a fraction of the fitted rate, covers the boards alone. Always check which you are looking at, since some composite systems also need slightly closer joist spacing that the frame must allow for.
Sources & further reading
Figures on this page are typical UK ranges drawn from published sources and depend on your specific garden. They are guidance, not a quotation.