Does composite decking get hot? What the colour does and what you can do

Composite decking gets hot in full sun, and a dark board on a deck with no shade can be too hot for bare feet by the afternoon. Some makers say their boards run hotter than timber. No brand gets around it. You control the colour and the shade, and you can check a sample in the real spot before you order.

Does composite decking get hot? What owners say

The makers say so in their own documents. NewTechWood says its boards get hotter than timber in direct sun because of the plastic content, and compares them to concrete on a hot day¹. Trex says its decking gets hot in direct sun like concrete or a timber deck does, and that the darker the colour, the hotter it feels². ModWood says its uncapped Natural Grain boards run at a similar surface temperature to timber of a similar colour, but that its darker colours can get quite hot underfoot, especially when new³.

Owners put it more bluntly. One Ekodeck Designer Series owner on ProductReview wrote in a five-star review that heat on sunny days makes it "impossible to walk on with bare feet"⁸. A one-star Ekodeck Classic review on the same site says the deck "seriously burnt kids feet"⁷. A Trex owner in Sydney wrote that any sun on it "burns the feet"⁹, and a NewTechWood owner added a note to their review that you cannot walk on it barefoot once it heats up¹⁰. One Millboard review says it can heat up badly in an Australian summer and another says it will burn your feet, yet a third owner on the same listing finds it easy to walk on in the heat¹¹. Back on the Designer Series listing, another owner says the heat doesn't seem much different to timber⁸. I read that spread as colour and site rather than brand, because the same listings hold both kinds of review.

On Whirlpool the story goes back further. A member who laid a small trial area of ModWood while choosing decking for a house built in 2010 wrote in September 2012 that they could stand barefoot on the timber beside it "but not on the modwood"¹². In the same thread, a member with an eight-year-old composite deck in the Northern Rivers said it gets hot, then shrugged: "stick a umbrella up"¹². A 2018 post describes a dark charcoal deck of hollow boards as boiling in the sun and unusable barefoot, and that owner was putting a roof over it¹⁴. A member planning a composite deck in 2024 put it most evenly: yes, it gets hot in summer, and "so does an oiled deck"¹³.

Why a composite board runs hotter than timber

NewTechWood puts it down to the plastic content. A composite board is wood fibre bound in plastic, and on a capped board the top layer is a plastic shell, which is exactly where your foot lands. ModWood's notes on its own uncapped boards point the same way. Each board has two faces, and ModWood says the darker smooth face, with more plastic at the surface, gets hotter, especially when new, while the brushed face feels cooler³.

The boards are made to sit in the sun, so the problem is your skin, your kids and your dog. The exception NewTechWood warns about is sunlight reflected off low-emissivity window glass, which it says can cause excessive heat build-up on nearby surfaces¹. If a big window looks straight onto the deck, I'd ask the maker about it before you order.

Colour matters more than brand

Trex's advice for hot climates is a lighter colour, or one of its colours with heat-mitigating technology². ModWood singles out its darker colours as the ones that get quite hot. The owner reports above come from five brands, and none of the makers claims a dark board stays cool. So I'd let the colour make the call before the brand does.

If you want the dark deck you saw online, check the aspect first. For a north- or west-facing deck with no roof, I'd choose a mid or light colour and put the samples side by side before deciding. Under a solid roof a dark colour is fine, because the boards never sit in full sun for long.

Aspect, time of day and shade

Where the deck faces decides when it is at its worst. A west-facing deck takes the full afternoon sun right when you want to use it. An east-facing deck gets gentle morning sun and goes into the shade of the house after lunch. North-facing decks get sun for most of the day in Australia, so they rely on colour and shade more than any other aspect.

The Cancer Council's UV guidance says UV is usually highest between 10 am and 4 pm⁶, and that is the stretch when the boards are taking the strongest sun. Plan the deck for how you will use it. A breakfast deck can be dark. A pool surround used at three in the afternoon in January cannot.

Shade is the strongest tool you have. The Northern Rivers member on Whirlpool said the heat is not a problem under a shade sail or an umbrella. A sail, a pergola with a solid roof or a deciduous tree on the west side will do the same job. If the shade is a someday job, buy the colour for the deck as it is now.

Cooler-board claims: what they mean

Some capped boards now come with technology meant to keep them cooler. Trex sells colours with what it calls heat-mitigating technology, and its own footnote says those boards stay cooler than its original boards but still get hot in direct sun, especially the darker colours². I read claims like this as a comparison against the maker's older boards. They don't make a dark board behave like a light one. Ask the maker what the claim is measured against and which colours carry it, because the Trex wording points you to colours that include the technology rather than to the whole range.

Does PVC decking get hot?

Yes, although some PVC makers claim an edge. TimberTech says its PVC boards stay cooler than many other deck boards, and its own footnote adds that all decking gets hot in the sun and darker colours feel hotter⁴. Futurewood, which sells both, credits PVC with slightly better heat dissipation than capped composite⁵. I'd treat that as a small edge rather than a reason to pick a dark board. The guide on what PVC decking is covers how else it differs.

Kids, dogs and pool edges

Parents and dog owners write some of the sharpest hot-deck reviews. The Sydney Trex owner calls it not ideal for anyone, especially children and pets. The Millboard owner who says it heats extremely hot in summer does not recommend it where there are pets or kids. A dog can't tell you its pads are burning and a toddler won't stop to think. If the deck is where the kids run out of the pool or where the dog lies in the afternoon, I'd make it a light-colour deck or a shaded one.

Around a pool the heat question sits beside the slip question, and the guide to composite decking around pools covers both.

The sample test you can do in an afternoon

NewTechWood tells buyers to test its boards barefoot before deciding¹, and this is the one test I'd insist on. Get full-size samples of the two or three colours you are choosing between. On a sunny day put them on the ground in the exact spot the deck will go, at the time of day you expect to use the deck. Leave them for two hours. Then put your palm on each one and hold it there.

You will feel the difference between colours straight away. Then do the same under whatever shade you plan to have. Bring a timber offcut if you have one and compare that too, so you know what you are trading. A sample is cheap and the deck cannot be recoloured later.

Put the samples on the surface the deck will sit over rather than on grass, because grass keeps them cool. Test on a still day, since a breeze hides the worst of it. Touch the dark colour last, so your hand is not already warm.

If you already have a hot deck

Shade is the fix that works. Everything else is a patch. A hose-down cools the surface for a short while before it dries. Outdoor rugs help in the walkway spots, but check your maker's care advice first, because Trex warns that rugs with a rubber backing or made from polypropylene can draw colour out of its boards². One thing I would not do is paint the boards a lighter colour. Trex, for one, says painting or staining may void its fade and stain warranty², and the guide on whether you can paint composite decking goes through the rest.

What I'd do

Pick the colour for the sun the deck actually gets, not for the photo. For a west- or north-facing deck with no roof, choose a light or mid colour and plan some shade. Under a solid roof, choose whatever you like. Test samples on site before you order, and where there are kids or dogs let that test make the call. If you are still choosing a board, read the capped vs uncapped guide for what the cap changes. Once the deck is down, the cleaning guide covers the upkeep. When you have a colour, the deck designer will draw the layout and the materials list for it.