Achieving LEED Status Through Urban Gardening
Urban agriculture can apply a wide number of credit points when certifying a building with the USGBC (United States Green Building Council). The major categories that relate to urban gardening are Sustainable Sites, Water Efficiency, and Innovation & Design. The following information comes from the New Construction Guidelines from the LEED handbook.
This category of LEED certification focuses on the project site, considering its physical setting as a functional relationship between the building itself and the surrounding natural ecosystem. The more the project site provides or accommodates to natural functions and ecological services, the more credits it will receive.
Stormwater design credits are designed to help prevent runoff and infiltrate rainwater on site. Urban gardening can be utilized to earn credits in this category by installing rain barrels and (or) using vegetative roofs. Rain barrels and vegetative roofs may synergize with water efficiency credits. Stormwater design may earn two separate LEED credits.
Heat Island Effect
Urban gardening can help with reducing the, “heat island effect”. A heat island is created in urban settings where hardscapes (asphalt, pavement, etc.) absorb sunlight and radiate heat to the surrounding environment. To reduce heat island, the urban gardening solution would be to install a vegetative roof to reduce sunlight absorbed and radiated from the roof. Heat island effect reduction for roofs can earn one LEED credit.
Important: Vegetative roofs are roofs that have plants growing on top of them and a significant portion of the roof must be covered. Generally speaking, Green roofs are roofs that are covered with paint that has a solar reflective index (SRI) of at least 29 (100 is most reflective).
Water use reduction is a broad category that takes a comprehensive and quantitative approach to measuring water savings. To earn credits in water reduction there needs to be a significant percentage reduction from the building’s benchmark water use. Urban gardening allows water to be captured from the environment to be used in landscaping to reduce water consumption by the building.
Water Efficient Landscaping
Efficient landscaping is an enormous part of what urban gardening is. The goal of urban gardening is to take a wasteful system and re-engineer it to be productive. By using bubbling or drip irrigation, significant water reduction can be achieved. By landscaping for the building’s native plant life, less water will need to be used. Urban gardening also offers decorative hydroponic, aquaponic, and vertical gardening systems that can be used as a landscape feature, as well as act as a productive source of food.
Innovative Wastewater Technologies
Wastewater can be dealt with in several ways. The most popular way is to make sure that water infiltrates on-site to recharge the water table. Infiltration can be achieved by using permeable pavement and by using native landscaping to absorb water, rather than divert it to storm drains. Rain gutters can be drained into rain barrels to capture water for use in irrigation. If one inch of rain falls on a 40-foot by 70-foot roof, 1,743 gallons of water could potentially be captured.
Innovation & Design
Innovation and Design credits are awarded for exemplary performance in other areas of LEED. These credits typically synergize with other credits that count for double points in multiple categories. This category recognizes innovative building features and sustainable building practices that exceed requirements of existing LEED credits.
Measurable Environmental Benefit
To prove that an urban gardening system is working, there must be metrics associated with specific goals. For example, if a rain barrel is installed for water catchment, the volume of water diverted should be reported. If the irrigation system is converted-drip or bubble irrigation, the amount of water saved should be reported. These metrics should exceed the LEED general requirements to count as exemplary performance.
Teaching Point (for Schools)
If a school implements an innovative solution for building efficiency, there’s an option to count it as a teaching point. If the school proves they’re using the solution to teach people about its environmental impact, credits can be earned. A school may also be able to use principles of native gardening, vegetative roofs, aquaponics, hydroponics, and water reuse as teaching points.
LEED offers many opportunities to use innovation and technology to improve building sustainability. Urban gardening satisfies many of the requirements to earn LEED credits, and can be a significant portion of credits earned.Featured Image: Rain barrels can provide essential irrigation and water-saving functions, as well as serve towards obtaining LEED certification credits. Image via Ingimage.com