Rooftop Gardens: How Green Are They?

St. Louis Rooftop Garden

When we think of gardens, we typically think of building them from the ground up. But with urban landscapes wiping out a good portion of available green space in cities, gardens are starting to gain heat from the top down.

Though the concept of rooftop gardens might seem nontraditional, they’ve been around for several generations. However, in recent years they’ve been gaining popularity as “going green” has become a high priority for urban planners. As an environmentally friendly option, rooftop gardens provide several advantages. We’ve listed out some of the top benefits rooftop gardens provide us.

Environmental Advantages

Rooftop GardenImproved air quality. Plants naturally absorb carbon dioxide  and release oxygen back into the air we breath. They also help capture and remove airborne pollutants. In areas that are very congested, planting a rooftop garden will help reduce air pollution levels by filtering noxious gases.

Increased storm water management. As cities grow, more and more permeable surfaces are being replaced with impervious surfaces, such as buildings and roads. Rooftop gardens are beneficial in reducing rainfall runoff impacts because they retain the water that falls on them and returns it into the air through transpiration and evaporation. Just as rooftop gardens clean the air they also clean the water by removing nitrogen pollution from stormwater runoff. They also delay peak flow periods, decreasing the stress on sewer systems.

Moderates the Urban Heat Island effect. Traditional rooftops radiate heat back into the environment by absorbing more sunlight than natural, plant based landscapes and radiate the suns energy as heat when the air cools, causing air temperatures to spike. This is known as the Urban Heat Island effect. Tall buildings with more surface area absorb and reflect the sun’s light, adding
to the effect. Rooftop gardens, on the other hand, dramatically lower surface temperatures on roofs. Studies have shown that traditional rooftop surfaces are comparatively 50 degrees hotter than rooftops with gardens.

Reduces energy consumption. Just like plants absorb water, they also absorb light and heat, insulating buildings better than traditional rooftops. This in turn contributes to the cooling the environment around them. As the plants help insulate buildings and cool the air around them it helps conserve energy and lower energy bills keeping internal temperatures cooler on hot summer days.

Encourages ecosystem life cycles. Naturally, gardens attract pollinating insects like bees and butterflies which will help local ecosystems. Rooftop Gardens

Taking advantage of the space on your roof is making gardening in the city a lot easier. And the benefits rooftop gardens provide exceed well beyond this list!

There are several things to take into consideration when designing a rooftop garden for your building. Things such as structural integrity, sun exposure, heat, and wind all play a factor into what goes into your garden. Our design team can help can help you implement your big project! We understand the elements of plant form and function and the fundamentals your garden requires for quality assurance. Contact us today by giving us a call at 314-770-2828 or using our simple contact form to discuss your rooftop garden needs!





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