Imagine walking your outdoor space on a summer afternoon with a thermal camera. The yard you know would light up in patches: a warm glow on the slide, brighter spots on open ground, and cool pools of blue wherever shade falls.
That picture is the most useful way to think about heat in a play space. It isn't one temperature; it's a map. Some spots are comfortable all day, and a few quietly get very warm. The good news is that the warm spots are predictable, which means they can be designed out.
This guide walks through where the heat hides, what the research found, and the choices that make the biggest difference when you're planning or upgrading an outdoor space.
What the research measured
Shade is the single biggest factor: in a side-by-side test, every surface dropped by roughly 13 to 43°C once it was shaded.
Western Sydney University researchers placed common playground surfaces in full sun and under a shade structure on the same hot day, then recorded the peak temperature of each.
| Surface | Peak in full sun | Peak in shade |
|---|---|---|
| Synthetic turf, 40mm pile | 84.5°C | 41.7°C |
| Dark green EPDM rubber | 77.8°C | 39.6°C |
| Dark brown TPV rubber | 71.8°C | 39.7°C |
| Natural grass | 55.1°C | 34.0°C |
| White rubber (lightest tested) | 48.7°C | 35.7°C |
Three things stand out. In shade, the gap between surfaces almost disappears, and none reached the temperatures the study treats as a burn risk. Colour matters a lot in full sun, with the white surface running far cooler than the dark ones. And even natural grass gets warm once the sun is on it.
The same team measured equipment too. In full sun, plastic swing seats, wooden benches, metal platforms and plastic slides all ran well above air temperature. Heat isn't a ground problem or a rubber problem; it's a sun problem.
It's not just the hottest days
A mild, sunny day can still produce a very warm surface, so heat planning isn't only for heatwaves.
In a report for the NSW Chief Scientist, the same researchers recorded a Sydney playground surface at 75°C on a day when the air only reached 28°C. What drives surface heat is direct sun, not the number on the weather forecast.
They also estimated that conditions warm enough to make unshaded surfaces uncomfortable could occur on roughly a third of days across a Western Sydney year. For a childcare centre, that's most of the outdoor play calendar from spring to autumn, not a handful of scorchers.
Five ways to design the heat out
The warm spots on your heat map come from a handful of choices, and each one can be made differently.
1Plan shade around your play times, not midday
Shade structures are usually positioned for the sun overhead at noon, but the shadow moves through the day. Stand in the yard at the times children actually go outside and see where the shade falls then. Prioritise the places children sit, climb and land: under equipment, along the bottom of slides, and around sandpits.
2Choose lighter colours for rubber
In the Sydney playgrounds the team measured, light-coloured rubber ran about 11°C cooler than black rubber in full sun. Colour is one of the easiest decisions to get right at design stage.
Bounce TPV comes in 20 standard colours plus custom blends, and the Bounce Colour Mixer lets you build and preview a lighter blend online before you commit.
3Keep synthetic grass short and dense
Longer blades hold more heat. In testing, 40mm turf ran about 4°C warmer than 30mm and about 10°C warmer than 13mm.
For play areas, a shorter, denser grass such as our 25mm Deluxe Landscape Grass (backed by a 16-year warranty) or 30mm Premium Landscape Grass suits a busy yard better than a long, plush lawn.
4Ask what's in the infill
The infill between the blades affects surface temperature too. Published studies have found organic infills running cooler than traditional rubber crumb.
Our Olive-Pit Infill is made from crushed, graded olive stones, holds a little natural moisture, and is rated Class 1 for surface temperature in independent lab testing.
5Keep surfaces in good condition
Surfaces change as they age. One Sydney study found an older synthetic turf playground running about 6°C warmer than new turf.
Regular brushing, topping up infill and fixing worn patches keep a surface performing the way it was designed to, and an ageing surface is worth factoring into your upgrade plans.
Don't trade fall protection for comfort
A cooler surface still has to do its main job: protecting children when they fall.
It's tempting to swap a hot surface for whatever looks coolest, but under climbing equipment the surface needs a critical fall height that meets or exceeds the equipment's fall height. Grass on its own doesn't do that; it needs the right underlay beneath it, such as a shock pad, tested as a complete system. The same goes for rubber, where the depth of the base layer does the work.
The best outcome is both: shade and a cooler surface on top, with a tested build-up underneath. If you're unsure what your current surface is rated to, our guide AS 4422 Explained walks through how to check.
Make your own heat map in five minutes
You don't need a research team to map your own yard; an inexpensive infrared thermometer from a hardware store is enough.
- Pick a warm, sunny day and do a round at the times children usually head outside, for example mid-morning and early afternoon.
- Check the same spots each time: the ground under each piece of equipment, slide surfaces and exits, benches, and any open ground with no shade.
- Note where the shade actually sits at each time, not where you expect it to be.
- Mark the warmest spots on a simple sketch of your yard.
- Share the sketch with your team, so everyone knows which areas to use first on warm days, and with your landscaper if you're planning works.
That sketch is one of the most useful things you can hand a landscaper or architect. It shows them exactly where shade, colour and surface choices will make the biggest difference.
Planning an upgrade over the break?
The summer shutdown is the natural window for outdoor works, and the best results come from deciding on shade, colour and surface together, with fall protection built in from the start.
Aloro Group has supplied rubber softfall and synthetic grass to Australian projects for more than 20 years. If you'd like help choosing colours, grass or infill, or would like us to talk directly with your landscaper or architect, call 1300 052 398 or email sales@aloro.com.au.
Sources
- Pfautsch, S., Wujeska-Klause, A. & Walters, J. (2022). Outdoor playgrounds and climate change: Importance of surface materials and shade to extend play time and prevent burn injuries. Building and Environment, 223.
- Pfautsch, S. & Wujeska-Klause, A. (2022). Synthetic Turf in Public Spaces: Systematic Assessment of Surface Temperatures. Western Sydney University for the Office of the NSW Chief Scientist and Engineer.
