Cooling Buildings with Rooftop Gardens

Cities often become hotter than nearby rural areas because roads and buildings absorb sunlight during the day and release heat slowly at night. Rooftop gardens cannot solve this problem alone, but they can reduce the temperature of individual buildings. Plants shade the roof, and water released from leaves cools the surrounding air.

A school in Easton compared two roofs during a summer experiment. The roof covered with plants was 31°C at noon, while the bare roof next door was 38°C. The classrooms below the green roof used less air-conditioning electricity, although the exact amount changed with the weather.

Rooftop gardens also hold some rainwater. This can reduce the amount of water that quickly enters drains during a storm. However, a garden must be designed carefully. Wet soil is heavy, and older buildings may need structural checks before a garden is installed. Plants also need regular care, especially during dry periods.

The Easton project involved students. They measured roof temperatures, recorded rainfall, and interviewed the building manager. Their presentation concluded that rooftop gardens are most useful when they are planned together with other measures, such as shade trees and energy-efficient windows.

Presentation Slides: Rooftop Gardens

1. Why cities get hot

• Roads and buildings [__1__] sunlight and release heat slowly.

2. Possible benefits

• Plants can shade roofs and cool the air.
• Gardens can hold some [__2__].

3. Points to check

• The weight of wet [__3__] may require a structural check.
• Plants need regular care during dry periods.

4. Easton students' conclusion

• Rooftop gardens work best as part of a [__4__] plan.

Cooling Buildings with Rooftop Gardens

Cities often become hotter than nearby rural areas because roads and buildings absorb sunlight during the day and release heat slowly at night. Rooftop gardens cannot solve this problem alone, but they can reduce the temperature of individual buildings. Plants shade the roof, and water released from leaves cools the surrounding air.

A school in Easton compared two roofs during a summer experiment. The roof covered with plants was 31°C at noon, while the bare roof next door was 38°C. The classrooms below the green roof used less air-conditioning electricity, although the exact amount changed with the weather.

Rooftop gardens also hold some rainwater. This can reduce the amount of water that quickly enters drains during a storm. However, a garden must be designed carefully. Wet soil is heavy, and older buildings may need structural checks before a garden is installed. Plants also need regular care, especially during dry periods.

The Easton project involved students. They measured roof temperatures, recorded rainfall, and interviewed the building manager. Their presentation concluded that rooftop gardens are most useful when they are planned together with other measures, such as shade trees and energy-efficient windows.

Presentation Slides: Rooftop Gardens

1. Why cities get hot

• Roads and buildings [__1__] sunlight and release heat slowly.

2. Possible benefits

• Plants can shade roofs and cool the air.
• Gardens can hold some [__2__].

3. Points to check

• The weight of wet [__3__] may require a structural check.
• Plants need regular care during dry periods.

4. Easton students' conclusion

• Rooftop gardens work best as part of a [__4__] plan.