Composite vs timber decking: cost, heat and upkeep
Timber is cheaper at the budget end, stays cooler in the sun and can be sanded back, but it needs oiling to hold its colour. Composite costs more than merbau or treated pine, comes in fixed factory colours, needs little more than a wash, is usually laid with hidden clips, and carries makers’ warranties of 10 to 50 years or more. Neither is better for every deck: the choice comes down to budget, sun, upkeep and the look you want.
How much does composite decking cost compared with timber?
These are typical reference prices gathered in November 2026 from Australian retailers (including GST) and US retailers (before sales tax). They vary by state, store and week. The per m² column is boards only, at each board’s width and gap, before offcuts, fixings and framing.
| Australia | Per lineal metre | Per m² of deck |
|---|---|---|
| Treated pine 90 × 22 | about $4 | about $42 |
| Merbau 90 and 140 × 19 | $5.72 to $9.95 | about $60 to $70 |
| Blackbutt 86 and 130 × 19 | about $10 to $10.50 | about $78 to $110 |
| Spotted gum 86 and 135 × 19 | $11 to $18.32 | about $120 to $130 |
| Ironbark 86 and 135 × 19 | $14.63 to $24.23 | about $160 to $175 |
| Ekodeck, five ranges | $14.55 to $26.30 | about $100 to $140 |
| Eva-Last, Infinity to Pioneer | $23.35 to $41.67 | about $165 to $275 |
| Trex, Select to Transcend | about $28.60 to $43.95 | about $200 to $300 |
| United States | Per lineal foot |
|---|---|
| Pressure-treated pine 5/4×6 | under $1 |
| Western red cedar 5/4×6 | from $3.60 |
| Garapa, tigerwood, cumaru, ipe 5/4×6 | $3.78 to $9.03 |
| Trex, Enhance Basics to Transcend | $2.33 to $7.15 |
| TimberTech, Prime+ to Advanced PVC Vintage | $3.51 to $7.83 |
| Fiberon, Good Life to Promenade PVC | about $3 to $7.70 |
A 5½ in. board with its gap covers about 2.1 lineal feet per square foot of deck.
So a mid-range composite such as Ekodeck costs about the same per square metre as spotted gum and less than ironbark, premium composite costs more than any timber here, and merbau and treated pine are hard to undercut. The frame can change too: 19 mm hardwood spans 500 mm joists, while Ekodeck Essentials, Eva-Last Infinity and Trex Select want 400 mm (in the US, 5/4 wood and these composites all use 16 in.). Most composite makers also want extra support under every butt joint, or a breaker board. See deck joist spacing for more.
Is composite decking hotter than timber?
In full sun it can be. Composite and PVC boards often get noticeably hotter underfoot than timber, and dark colours more than light ones. Makers say as much: Trex sells Transcend Lineage and newer Select colours with heat-mitigating technology, and Eva-Last’s installation guide allows for boards in sun running 25 to 30 °C above the air temperature when working out expansion gaps.
Heat also makes composite grow in length, so its end gaps change with the temperature on the day: Trex asks for 3 mm above 4.5 °C and 5 mm below (1/8 in. above 40 °F, 3/16 in. below). If the deck faces the afternoon sun and people go barefoot, timber or a light composite colour is the comfortable pick.
How much maintenance does each need?
Australia
Timber wants oiling when new and every so often after, or it weathers to grey. Treated pine in particular needs regular oiling or it greys and checks. Merbau bleeds tannin when new, which can stain paving below. The upside is that timber can be sanded back and re-oiled to look new.
United States
Pressure-treated pine, cedar and redwood weather to grey unless sealed or stained, and wet treated boards shrink after laying, so they go down tight.
Capped composite and PVC have a plastic shell that resists stains and fading, which is what the makers’ stain and fade warranties cover. They need washing rather than oiling. Uncapped composite such as Ekodeck Classic can be re-sanded, like timber.
How long does composite decking last compared with timber?
In Australia, timber durability is rated by class for heartwood above ground: Class 1 is expected to last more than 40 years and Class 2 from 15 to 40. Merbau, blackbutt, spotted gum and red ironbark are Class 1; jarrah is Class 2. Treated pine relies on its H3 treatment. Sapwood isn’t durable in any species. In the US, the code counts the heartwood of redwood and cedar as naturally durable, and treated deck boards should be rated UC3B.
For composite, the makers’ limited warranties are the best guide: Ekodeck 10 years (Essentials) to up to 30 (Summit), Eva-Last 25 to 30, Trex 25 (Enhance) to 50 (Transcend, Lineage), TimberTech 25 to 30 on composite and limited lifetime on Advanced PVC, and Fiberon 25 to lifetime. They depend on installing to the maker’s guide. In either material, ventilation and ground clearance matter as much as the board.
Hidden fixings vs face screws
Most composite boards have grooved edges for hidden clips: Ekodeck Quickfix, Eva-Last CHAIN, Trex Hideaway, TimberTech CONCEALoc and Fiberon EDGE. There is one clip per joist, the clip sets the gap, and no screw heads show. The trade-off is cost and access: clips run about $0.38 (Ekodeck, in a kit) to $1.31 (Eva-Last) each in Australia and $0.44 to $0.87 in the US, against about $0.14 for a stainless decking screw in Australia and $0.07 for a coated deck screw in the US. Lifting one board in the middle of a clipped deck is also more work.
Face screwing composite depends on the brand. Trex allows two screws per joist, driven flush. Ekodeck only allows it on the last ripped board and the fascia, and face-fixing the whole deck voids its warranty.
Australia
Timber boards are square-edged and face-fixed: two fixings per board at every joist, at least 12 mm from edges and ends, pre-drilled near the ends. Use hot-dip galvanised or stainless fixings, never electroplated, and stainless within 1 km of the coast or 1 m of a pool.
United States
The IRC asks for two 8d threaded nails or two No. 8 wood screws at each joist for wood decking (R507.7), with hot-dip galvanized or stainless fasteners, and stainless within 300 ft of salt water.
What about bushfire and wildfire areas?
Australia
At BAL-29 decking must be a bushfire-resisting timber such as merbau, blackbutt, spotted gum or red ironbark, a tested composite, or non-combustible. Treated pine doesn’t qualify. Ekodeck Designer, Summit and Flame Fighter, Eva-Last Infinity and Trex Transcend are tested to BAL-29.
United States
In California’s wildfire zones, decking within 10 ft of the house must meet the state’s ignition-resistance rules. Trex Transcend, Lineage and Select, TimberTech Advanced PVC and Fiberon Promenade are listed as WUI compliant; Trex Enhance is not.
So is composite decking worth it?
- Choose timber if budget comes first, the deck sits in hot sun, or you like real grain and don’t mind oiling now and then.
- Choose composite if you want a screw-free surface, a set colour and the least upkeep, and its price sits close to the hardwood you were weighing up.
Common questions
Is composite decking cheaper than merbau?
No. At November 2026 reference prices merbau boards cost about $60 to $70 per square metre of deck, while composite ranges start around $100 per square metre for boards alone.
Does composite decking get hot?
In full sun it can get noticeably hotter underfoot than timber, and darker colours are hottest. Some makers offer heat-mitigating ranges, and lighter colours help.
How long does composite decking last?
Makers back their boards with limited warranties from 10 years on entry ranges to 50 years or lifetime on premium ones. Class 1 Australian hardwoods such as spotted gum are expected to last more than 40 years above ground.
Can you face screw composite decking?
Some brands allow it, such as Trex with two flush screws per joist. Others, such as Ekodeck, only allow face fixing on the last ripped board and fascia, and fixing the whole deck that way voids the warranty.
Which needs less maintenance, composite or timber?
Composite. Capped boards need washing rather than oiling, while timber needs oiling to keep its colour and greys if left alone.
This guide explains common rules in plain words. It isn’t engineering advice: span tables, footings and barriers depend on your timber grade, soil, wind and local rules. Have a builder, certifier or building department check your design before you build.