The arresting leaf coverage on the exterior walls of the Banco Popular Foundation’s newly inaugurated headquarters in Hato Rey offers the most recent public evidence of the green building revolution that is slowly but progressively taking hold in Puerto Rico.
The “hanging gardens” on the front and back of the five-story building, which the foundation shares with 11 nonprofit organizations devoted to improving the quality of life on the island, enhance Banco Popular’s environmental credentials while letting it reap the benefits tied to this type of installation.
A layer of plants, grasses, shrubs and other flora on a rooftop or side wall helps to insulate a building and lowers the cost of cooling, or heating, the structure. Green roofs also reduce storm water runoff, help lower the urban heat island effect, improve air quality, and provide wildlife habitat.
Banco Popular plans to keep track of the building’s energy consumption to assess the financial benefits of its green strategy.
“This type of free wall is being evaluated for future use in new or existing buildings based on its benefits,” the bank said in a statement.
Green walls and green roofs are gaining traction everywhere.
Washington, D.C., Chicago, New York city and Toronto are among the cities with the most green roofs in North America and earlier this month, France decreed that all new rooftops must be covered in plants or solar panels.
Green roofs ‘take root’
While the green wall at Banco Popular Foundation is possibly the first of its kind in Puerto Rico, green roofs have been taking root in San Juan since the 90s, according to green roof specialist David L. Aponte. By his estimate, there are more than 200,000 square-feet of green roofs in Puerto Rico, mostly in the metropolitan area.
It’s all part of the larger green building phenomenon taking hold as a result of greater environmental awareness and the need for cost efficiencies providing long-term financial savings to both the public and private sectors. Also, green buildings are considered to be good for employees, contributing to greater productivity, health and general wellbeing, which in turn spells out corporate savings.
Interest in green building has been growing in Puerto Rico over the past two decades.
“It’s only in the last 20 years that there has been an awakening of ecological conscience regarding building,” said 40-year veteran architect Fernando Abruña whose firm in partnership with wife Margaret Musgrave — A & M Architects — is behind various green building designs and projects, including three schools, two of which, Carmelo Feliciano in Culebra and the Eco Elementary School in Dorado, boast green roofs.
A & M Architects’ designs include a sustainable two-bedroom home, sold under the name Solaria by Compañia Villas Mi Antojo, that features compost toilets, a rainwater collection system and photovoltaic panels. Mi Antojo has sold three of them, each priced at $90,000.
The firm also has designed a sustainable one-room, 215-square-foot house that Abruña said he can build for $30,000, excluding the cost of land (the price will jump to $35,000, if the government goes ahead with plans to switch over to a value-added tax on purchases and services.) Marketed under the name of eCobito, this tiny house is off-the-grid, meaning it does not require to be connected to running water or a power grid.
Abruña’s sustainable buildings are wrapped in a two-inch layer of foam insulation, which helps keep the structure cool for lower energy costs. He also favors natural ventilation, rainwater harvesting, gray water reuse and solar water heating.
His firm’s private commissions include an $800,000 home in the island’s southwest area featuring a Moon Lamp to capture the light of the full moon on 39 nights of the year.The firm’s LEED projects include the Dr. Cayetano Coll y Toste elementary/middle school in Arecibo.
Level of construction is low
Despite growing interest in Puerto Rico, the level of green construction is small at least as reflected by data on LEED-certified projects. LEED, which stands for Leadership in Energy & Environment Design, is the green building program most in use around the world.
To date, only 35 buildings on the island have earned LEED certification while another 30 projects have an Energy Star certification (energy efficiency standard,) said Abruña.
The certified LEED-buildings are among 119 local projects registered for LEED certification as of Sept. 2014, according to the Caribbean Chapter of the U.S. Green Building Council (USGBC). Certification is a lengthy process that can take up to 36 months, especially in the case of existing buildings.
With four rating levels (Certified, Silver, Gold, Platinum), LEED certification offers independent proof of a building’s green features and covers a building’s design, construction, operations and maintenance.
“LEED works for all buildings at all phases of development, from new construction to existing buildings, as well as all building sectors, from homes to hospitals to corporate headquarters, ” according to USGBC.
“Business owners are looking for alternatives to save energy and be more efficient. Data has shown that LEED-certified buildings can achieve energy savings of up to 50 percent,” USBGC Caribbean Chapter President Jesus A. Garay said in an interview last year.
LEED-certified buildings also have a higher rentability and resale value.
Architect Richard Cuebas blamed the island’s long-running recession for holding back green building development, which, he said, had been picking up momentum prior to 2007.
“It’s not that there is a lack of knowledge, it’s that there aren’t the economic incentives,” said Cuebas, a partner at Integra Design Group Architects & Engineers, PSC.
The firm’s LEED projects include the Dr. Cayetano Coll y Toste elementary/middle school in Arecibo. The $15 million project also incorporated a 1,300-square-foot green roof that, he said, has become a learning tool for the 600 students at this public school.
If green building have yet to fully take off on the island, the integration of sustainable elements is by now commonplace, according to Cuebas, who presides the Puerto Rico chapter of the American Institute of Architects.
“Our clients want a building to be efficient and healthy,” he said, ticking off the more common sustainable features sought by companies these days.
These include high efficiency lighting, HVAC technology for thermal comfort and improved indoor air quality, and efficient water use. Coll y Toste school, for example, collects and stores rainwater in a cistern for use in flushing toilets.
“In a typical building, 20 to 25 percent of the investment cost is tied to sustainable components,” said Cuebas.
Green roofs not first option
As for green roofs, he said they are probably not the first option a company would consider also because a building may not lend itself for such a project, especially if it’s an old structure being retrofitted.
Where possible, a green roof offers a practical solution to increasing a building’s efficiency and is important, according to Cuebas, because “it is a way for a company to prove its commitment to sustainability.”
This holds true for a public agency too.
Take the Jardín Mirador Ballajá set up in 2012 atop the Cuartel de Ballajá on the grounds of El Morro in Old San Juan, home to several cultural organizations and the Las Américas Museum.
Its rooftop “garden” shares roof space with 720 photovoltaic panels that can generate 150 kWh, providing for a savings of 50 percent in energy consumption, according to Marel Del Toro, a specialist on historic structures at the State Historic Preservation Office which oversaw the ambitious project as part of a larger, $1.5 million rehabilitation of this public building begun in 2009. In a 2011 visit to Puerto Rico, President Barack Obama praised the building as “a model of energy efficiency.”
The garden, which has a very extensive coverage for weight considerations and easier maintenance, features in excess of 67,000 plants from more than 24 different species including “liriope,” aloe, “limoncillo,” rosemary, mint, basil, chives and succulent plants.
Plans to open the garden to the public remain currently on standby due to ongoing work in connection with a drainpipe problem. Once open, it would be the only public rooftop garden in San Juan, according to Del Toro.
Green roofs are not generally designed as accessible spaces, however. They are complex projects that involve many aspects such as sealing the roof, setting up proper drainage, laying a membrane to prevent roots from growing and installing filter materials. Some require irrigation systems.
Typically, a roof specialist, an architect and structural engineer will work together to plan the roof.
“You have to consider the maintenance to equipment that may be on the roof as well as the sun orientation,” Cuebas said.
The average cost of a green roof in Puerto Rico is $35 per square foot, not including sealing and insulating the roof, he said.