Gardens of the Château de Villandry, Indre-et-Loire Department, France (47°20’N, 0°30’E).

At the University of Hawai’i at Manoa, Leyla Cabugos has been working on a “Green Roof Experiment.”

When most people hear the term “Green Roof” they most likely associate it with solar panels or some sort of new “green” technology to increase energy efficiency.

Well, this kind of green roof has a more literal shade of green. Probably considered to be more of a biological or botanical breakthrough, it still has some profound energy benefits without the high costs of new technologies.

“Green roofs are permanent layers of vegetation on built structures, used to moderate building temperature, decrease storm water runoff, increase available green space in urban areas throughout the world.”

In an attempt to “green” urban areas Cabugos has put together a project where five native Hawaiian plant species offer a more efficient rooftop solution. The use of these stress tolerant and local plant species were two of the most important factors in the experiment.

There are many sustainable benefits to these green roofs. In addition to the pure aesthetics of adding more green scenes to the concrete jungles, the living roof will offer sustainable benefits such as reduced head load and cooling needs for the building resulting in energy conservation, as well as reducing water runoff.

Green roofs also offer a unique opportunity for a creative use of the space. Some have been developed for recreational purposes such as a mini golf course. Others have been used for community building and other social benefits.

One of the most prominent and sustainable examples is located on top Vancouver’s Fairmount Waterfront Hotel. Growing herbs and vegetables on the rooftop garden saves the kitchen over $30,000 annually in food costs!

We should expect to see some tax incentives emerge from government legislation at the state and municipal level in the near future.

The experiment in Hawai’i has drawn much attention from local businesses looking to implement a similar living roof project on top of their facilities. However their progress has faced some challenges.

“Despite extensive implementation and research on the positive impact of green roofs throughout the world, the practice has yet to become popular in Hawai`i, where the benefits are likely to be amplified by year-round sunshine and frequent rains.”

Cabugos firmly believes “it is a very compelling tool offering a vast array of benefits- particularly here on the islands.”

Her specific experiment is “meant to use native plants in a simple design that is widely applicable as well as low maintenance.”

She hopes that her work and research will push several state and national initiatives to start the widespread adoption of green roof practices in Hawai’i and other urban locations nationwide.

Leyla Cabugos is a recent UH Gradaute (MS Botany). Cabugos works for the STEM Workforce Development Program Office at the University of Hawai`i at Manoa, consults on green roof and urban agriculture projects and is currently working on an aquaponic rooftop garden. She can be contacted by writing to cabugos{at}gmail.com.