Decking is one of the most popular garden additions in the UK, but the choice between timber and composite divides opinion — and budgets. Timber costs less upfront; composite costs more initially but demands almost no ongoing maintenance. The right answer depends on how much you value your weekends.
What Does Decking Cost?
Installed prices in 2026:
| Decking type | Material cost (£/m²) | Installed cost (£/m²) |
|---|---|---|
| Pressure-treated softwood (pine/spruce) | £20–£35 | £120–£160 |
| Hardwood (balau, ipe, cumaru) | £40–£80 | £160–£220 |
| Entry-level composite | £40–£65 | £180–£220 |
| Mid-range composite (capped) | £60–£90 | £200–£240 |
| Premium composite (full encapsulation) | £80–£120 | £220–£280 |
Prices are 2026 UK averages. London and South East typically 20–25% higher. Assumes ground-level or low-rise deck on reasonably accessible site.
Worked Example: 20 m² Deck
| Cost element | Softwood timber | Mid composite |
|---|---|---|
| Decking boards | £500–£700 | £1,200–£1,800 |
| Subframe (treated joists + posts) | £400–£600 | £400–£600 |
| Fixings, clips, hardware | £80–£150 | £100–£200 |
| Labour | £700–£1,000 | £800–£1,200 |
| Total (approx.) | £1,700–£2,500 | £2,500–£3,800 |
Note: both use a timber subframe — there is no cost saving on the structural elements regardless of which board material you choose.
Timber Decking
Pressure-Treated Softwood
Treated pine and spruce are the most widely installed decking boards in the UK. They are widely available, easy to cut and fix, and significantly cheaper than composite. The main catch is maintenance: softwood must be cleaned and re-treated (oil or stain) every one to two years to prevent it greying, splitting, and becoming slippery with algae. Without treatment, softwood decking typically degrades visibly within three to five years.
Lifespan with proper maintenance: 15–20 years.
Hardwood
Tropical hardwoods such as balau, ipe (pronounced ee-pay), and cumaru are significantly denser and more naturally durable than softwood. They do still need oiling — typically every one to three years depending on exposure — but they are harder, less prone to splintering, and last longer. Sustainably sourced hardwood (FSC-certified) is available; verify certification before purchasing, as the hardwood supply chain has a history of mislabelling.
Lifespan: 25–30+ years with maintenance.
Slip Resistance
Timber becomes extremely slippery when wet and covered with algae — a real safety hazard in shaded UK gardens. Regular cleaning (pressure washing plus a decking cleaner) and treatment help. Grooved decking boards provide marginally better grip than smooth-faced boards. Anti-slip strips can be added retroactively.
Composite Decking
Composite decking is made from a blend of wood fibre and recycled plastic. Early products (pre-2015) had a poor reputation — they were prone to fading, mould and surface checking. Modern capped and fully-encapsulated composites are significantly better and come with manufacturer warranties of 15–25 years.
Composite Types
Uncapped composite: wood-fibre and plastic blend with no outer skin. Cheaper but still susceptible to moisture absorption and surface mould over time. Not recommended for UK’s wet climate.
Capped composite (single-sided or four-sided): an outer plastic shell bonded to the core protects from moisture, staining and UV fade. Requires minimal maintenance — a brush-down and occasional wash.
Fully encapsulated composite: the highest grade, with a thick co-extruded shell on all four sides. Extremely resistant to moisture, fading and staining. Warranties typically 25 years.
Composite Maintenance Reality
The appeal of composite is that it genuinely needs very little upkeep:
- Brush off debris regularly to prevent organic matter building up
- Wash down once or twice a year with soapy water or a composite-safe cleaner
- No oiling, staining or sealing required
Slip resistance is generally better than timber in wet conditions — most quality composite boards have a textured or grooved surface that maintains grip when wet.
Composite Limitations
- Cannot be reclaimed or recycled at end of life as easily as pure timber
- Higher upfront cost
- Looks “plasticky” to some eyes, particularly cheaper products
- Cannot be sanded back if the surface is damaged
Total Cost of Ownership
This is where the comparison really matters. Timber needs annual or biennial treatment.
| Scenario | Softwood timber (20 yr) | Mid composite (20 yr) |
|---|---|---|
| Initial installation | £2,100 | £3,200 |
| Annual maintenance product cost | £40–£80/yr | £0–£20/yr |
| Total maintenance over 20 years | £800–£1,600 | £0–£400 |
| Time spent on maintenance | ~6–8 hours/year | ~1–2 hours/year |
| Estimated total cost (materials only) | £2,900–£3,700 | £3,200–£3,600 |
Over 20 years, the total cost of ownership is roughly comparable — composite’s premium is largely offset by avoided maintenance spending. The real difference is the time and effort saved with composite.
Planning Permission
Decking is normally permitted development in England provided:
- The deck is no more than 300 mm above ground level
- It does not cover more than 50% of the total garden area
- It is not in a listed building’s curtilage or, for front gardens, adjacent to a highway
Raised decks over 300 mm typically require planning permission. Always check with your local planning authority if in doubt, especially in conservation areas.
Building Regulations
Domestic garden decking at ground level does not normally require Building Regulations approval. However:
- Any deck raised more than 600 mm may need approval (structural calculations and balustrade design)
- Balustrades must be designed to resist a horizontal load of 0.74 kN/m where the drop is 600 mm or more (Building Regs Approved Document K)
Choosing Between Timber and Composite
| Choose timber if… | Choose composite if… |
|---|---|
| Budget is the primary driver | You want near-zero ongoing maintenance |
| You are comfortable with annual treatment | You value your weekend time |
| You prefer a completely natural aesthetic | You want consistent colour for 20+ years |
| You may want to change the deck within 10 years | You want better wet-weather slip resistance |
Both are valid choices. The key mistake to avoid is buying cheap uncapped composite (it performs poorly in the UK climate) or softwood timber and then neglecting the maintenance schedule.
