Composite vs timber decking: is the extra cost worth it over ten years?
Composite decking costs more upfront than timber, but we work out whether the difference pays for itself across a typical ten-year lifespan.
A new deck in Britain typically costs £2,200 – £3,650, with composite boards sitting at the top of that range and treated softwood near the bottom. The question most homeowners actually want answered isn't "what does decking cost" but "is composite worth paying more for" — and the answer depends on how long you plan to keep the deck and how much time you want to spend maintaining it.
The upfront gap
For a typical 25 m² deck, we calculate labour hours and local material rates separately for each surface, then check the result against market quotes. On that basis:
- Treated softwood: £2,800
- Composite: £3,800
- Hardwood (balau, ipe): £4,150
| Material | Typical | Usual range | Lifespan |
|---|---|---|---|
| Treated softwood | £2,800 | £2,200 – £3,650 | 10-15 years |
| Composite | £3,800 | £2,950 – £4,950 | 25-30 years |
| Hardwood (balau, ipe) | £4,150 | £3,250 – £5,400 | 20-25 years |
Composite usually comes in a few hundred pounds above softwood for the same footprint, mostly because the boards themselves cost more — labour time is similar, since fixing composite isn't noticeably slower than fixing timber once a crew is used to the fixings.
Where the ten-year maths changes
Treated softwood needs re-oiling or re-staining roughly every one to two years to keep it looking good and to protect it from rot. Skip that and you're looking at boards cupping, splitting or greying within five or six years, often needing partial board replacement well before the frame underneath is due for attention. Composite needs none of that: an occasional wash is all it asks for, and the colour doesn't need topping up because it isn't a surface coating.
So the real comparison isn't the build cost alone — it's build cost plus a decade of upkeep. Re-oiling a 25 m² softwood deck is a half-day job if you do it yourself, or a paid visit if you don't; either way it adds up over ten summers in a way that's easy to underestimate when you're only looking at the initial quote. Hardwood splits the difference: it weathers well with no treatment at all if you're happy with it silvering, but costs more to buy than either of the other two options, so it rarely wins on pure economics.
Where timber still makes sense
Composite isn't automatically the better buy. If you're decking a small balcony or a deck you expect to replace or alter within five years — say, ahead of a wider garden redesign — the lower entry cost of softwood is hard to beat, and the maintenance burden never gets the chance to compound. Timber is also easier to repair locally: a cracked board is a trip to a timber merchant, while matching an exact composite profile a few years after the original run can mean ordering from the same manufacturer and hoping the colour batch hasn't changed.
Composite earns its premium on decks that are hard to get back to — raised decks, decks that back onto difficult access, or simply decks you don't want to think about again. Garden decking has the full range by size and specification if you want to model your own footprint.
Other costs that move the number more than the material does
Before fixating on composite versus timber, check these, because each one can shift the total by more than the material premium:
- Height. A raised deck off a back door needs a supporting structure, handrail and usually a flight of steps — all added cost on top of the decking surface itself.
- Old deck removal. Taking up and disposing of an existing deck adds to the job; it's worth pricing separately rather than assuming it's included.
- Ground conditions. Sloping or uneven gardens need extra groundwork for the frame regardless of which boards go on top.
None of these depend on the board material, so get them right first — they often move the total more than the softwood-to-composite jump does.
Checking a quote
Decking quotes vary a lot by region and by how a contractor prices groundwork versus boards, so it's worth checking any quote you receive against typical figures for your specification before accepting it. Our "is my quote fair" tool does that comparison for you, and it's a quick way to spot a quote that's loading cost into the wrong line item — for instance, charging premium rates for groundwork that should be standard.
If your garden also needs new boundary fencing alongside the deck, Fencing breaks down material options the same way, since the same build-cost-versus-upkeep trade-off applies there too — timber panels cost less to install but need more attention than composite screening over the years that follow.