Green roofs and rooftop gardens are increasing in popularity across Colorado and the United States, as urban dwellers seek to feel more connected to nature. They are beneficial for many other reasons, causing some municipalities to begin to require their inclusion when an existing roof is replaced. In fact, in November 2017, Denver voters passed a green roof initiative that requires the addition of some type of reflective roof or a form of green infrastructure. What are the benefits and why might you consider installing a green roof or rooftop garden on your commercial property? Read on to learn more.

Why Construct a Green Roof?
Rooftop gardens and green roofs provide a space where individuals can have some contact with nature in a place that it might be hard to come by, such as a large city. According to studies done in Landscape and Urban Planning Journal, “Nature experiences, including walking, relieve anxiety and negative effects of stress in adults and are associated with greater emotional well-being in children.” Non-profit organizations, such as Come Alive Outside, work with healthcare, public health, outdoor recreation and landscape profession partners to help get people outdoors in communities across North America.
Additional benefits of rooftop gardens & green roofs:
Rooftop gardens assist in reducing and filtering polluted air
The sun heats concrete and asphalt faster than plants and trees. More plant material in cities can help reduce temperatures and the urban heat island effect.
Green roofs provide good insulation, keeping the building cool in the summer and warm in the winter. This reduces facility heating and cooling costs.
Green roofs help reduce stormwater runoff and slows the water flow to storm drains and can reduce road flooding.
When you install a green roof or rooftop garden, your facility can earn LEED credits in certain categories such as:
- Reducing site disturbance
- Protecting or restoring open space
- Innovative wastewater technologies
- Innovative design
What Goes into Building a Rooftop Garden?
There are many factors to consider when constructing a green roof or rooftop garden. Here are some of the largest:
Getting Materials in Place
The first and main factor when installing a rooftop green space is getting material into position for the job. In most cases this is accomplished using a crane or telescopic forklift (depending on how many floors the building contains). Safety is very important in this process, so only having the most qualified personnel with proper training and certifications is of the highest importance.
Specialized Materials
Rooftops are often uneven surfaces that require specialized materials to make them an inviting outdoor living space. Six to 7 layers aid in waterproofing the area and protecting the building. Rooftop pavers are placed on a pedestal system to allow leveling of the space over the top of drainage and HVAC systems. Many of these pavers include the reflective quality required for LEED certification and to satisfy green-roof initiatives.
Plant selections should be made with careful consideration. If your rooftop is lacking in shade, plant material should be full-sun friendly. Since limited growing space is available, plants should be those that thrive without having to root deeply.

Irrigation
Another important factor in building a rooftop garden is the planning of the irrigation system. With irrigation pipes being exposed to freezing temperatures on the rooftop, draining the system regularly and winterizing it is necessary to keep the system functioning properly. Regular checks of the system are critical because small leaks can accumulate water on the rooftop and cause major water damage to the building’s infrastructure.
Interested in learning more about adding an eco-friendly rooftop garden to your commercial property? Timberline Landscaping has an experienced and capable construction team comprised of highly trained individuals that can help plan and execute your plans for a rooftop garden. Contact us to be connected with our commercial estimators.
