Open-air car parks are among the hottest surfaces in our cities. Asphalt, concrete and parked cars soak up the sun, so the heat stays long after the commuters have gone home. Planting trees is the usual fix, but a new tree takes 20 years or more to give useful shade, and it often costs parking spaces.
Tensile worked with Cumberland City Council and Western Sydney University to test another approach. The research was funded by the Office of the NSW Chief Scientist & Engineer. The Cool Roof System is a modular, freestanding steel frame carrying a stainless steel Webnet mesh roof. Fast-growing native vines (Wonga Wonga vine and Bower vine) are trained across guide wires to form a living canopy.
The Wentworthville installation is the second generation of the system. It builds on a prototype at Holroyd Gardens in 2023. The structure was engineered around the existing bay layout, so no parking spaces were lost.
Tensile’s role:
We designed, fabricated and installed the Cool Roof System, then supported the independent monitoring carried out by Western Sydney University.
Measured results:
- Surface temperatures reduced by an average of 19°C, and by up to 35°C
- “Feels-like” (black globe) temperatures reduced by up to 10°C
- 71% canopy coverage within 22 months, creating 100m² of usable shade
- An average of 74% of UV radiation and around 60% of near-infrared radiation blocked
- The hotter the day, the greater the cooling effect
Why it matters:
The Cool Roof System gives shade in under two years, not two decades. It works within existing car park layouts, needs no loss of parking, and is backed by independently monitored, government-funded research. For architects and councils, it’s a proven way to meet urban heat targets on hard surfaces where trees can’t easily grow.
Where it suits:
The system suits any at-grade car park that needs shade quickly without losing bays, including commuter and council car parks, schools, shopping centres and hospital campuses.
Read more:
For a closer look at the findings and what they mean for car park design, read our article Cool Car Park Design: How to Cut Surface Heat by 35°C.
Download the full results:
The complete Wentworthville monitoring report is free to download from our Resources page. To talk about a site assessment for your project, get in touch with our team.
