“Hot Playgrounds” and designing for thermal comfort

If you’re a member of Play Australia, you may have participated in last week’s online learning session featuring Dr Sebastian Pfautsch, Associate Professor in Urban Studies at Western Sydney University.

In the summer of 2020, Dr Pfautsch studied surface temperatures at three outdoor play spaces in early learning centres in Sydney. His findings were astonishing.

“The hottest surface that we found was 105 degrees, which was the inside part of a rubber tyre where metal was woven into the rubber — this was the record-breaking temperature,” he said.
“On summer days where you had air temperature of about mid-thirties, we found that soft fall rubber and astroturf was heating up to between 80 and sometimes above 90 degrees celsius.”

This new knowledge elevates thermal comfort and surface temperature considerations as key design considerations, so here are a few tips to reduce the risk of burns and ensure maximum comfort for all park-goers.

Shade

It’s not the air temperature that causes the majority of contact burns but direct sunlight exposure. The use of shade structures in light colours, and the addition of mature trees and plantings can greatly reduce the surface temperature of equipment and ground areas while also creating a more comfortable microclimate.

Trees and plantings improve microclimatic conditions through evapotranspiration, further reducing near surface air-temperature. While trees will take time to grow and develop, alternate structures such as green pergolas and arbours can be built and covered with climbing plants that will quickly grow and provide comfort and a beautiful outlook.

Generally, a shade budget is something that is tacked on at the end of a project or design; we have seen an increasing need for shade to be allocated additional funding and become a part of the integrated design, right from the outset. The Victorian government has mandated that all new school playgrounds must be shaded.

Softfall Choices

EPDM in the same colour is 15 – 20 degrees cooler than CSBR. If your budget won’t allow for EPDM, consider a loose softfall alternative or provide shade. Bark and sand softfall can reduce surface temperature while also providing an additional sensory element to the space. The use of artificial grass or AstroTurf should be avoided or restricted to areas with zero exposure to direct sunlight.

Consider Real Grass

We know that turf is harder to maintain; it requires watering, treatment and fertilisation, and if you get all of those factors right you also have to mow it! However, grass promotes elevated levels of physical activity in children, while also providing a surface temperature up to 30 degrees cooler than bare spoil in the same location. Consider integrating grey water and rainwater collection devices within the design to ensure those maintenance resources are available.

Bring back Nature

As urban densities increase, people’s access to nature and the natural environment is becoming more limited. Nature-inspired play and recreational spaces that consider extensive plantings and/or bio-corridors and provide multi-generational and all-abilities access are key to giving people access to these immersive, stress-reducing environments without having to travel. On the plus side, Nature-based playgrounds and timber equipment are generally cooler than rubber, steel and plastic equipment due to timber’s lower thermal and radiated heat properties.