This credit promotes biodiversity by encouraging project teams to protect existing onsite native habitat or restore the site with native species.
How you go about earning this credit will depend on the existing conditions of your project site. If you have a greenfield site—one that has not been built, graded, or otherwise altered by human activity—you are required to limit site disturbance during construction.
If your site has been previously developed, you must protect or restore a portion of the site—50% of the total area minus the building footprint, or 20% of the total site area, whichever is greater—and plant with native or adapted species. The protected or restored area can include vegetation, water bodies, soils, or other ecosystems.
Don’t confuse with SSc5.2
It’s easy to confuse the requirements of this credit, SSc5.1, with those of SSc5.2: Site Development—Maximize Open Space. While they both have the stated intent of promoting biodiversity, they’re actually quite different.
This credit focuses on protecting and restoring native habitat or limiting construction disturbances—depending on existing project conditions. Use of native or adapted species in landscaping is a key aspect of this credit.
SSc5.2, on the other hand, is aimed at increasing open space relative to local zoning requirements. It has no requirements for native vegetation—turf grass and even pedestrian-oriented hardscape could apply—and does not put restrictions on construction site disturbance.
What’s a green roof got to do it?
If your project is previously developed and earning SSc2: Development Density and Community Connectivity, you are allowed to include a vegetated roof with native or adapted species in your calculations. This clause allows dense urban sites to earn this credit even though they may not have enough exterior site area to qualify otherwise.
In order to comply with SSc5.1, green roofs must provide a diversity of native or adapted species that provide animal habitat. This means that extensive roofs with sedum monocultures won't contribute to this credit, as USGBC spelled out Iin LEED Interpretation #10231. Containerized plants are also unlikely to contribute. USGBC is looking for at least six inches of depth of growing medium—in line with an "intensive" green roof—and multiple species that are suited to provide native habitat. The Interpretation gives six species of sedum, on a six-inch growing medium, as an example of an acceptable green roof, as far as contributing to this credit.
Other options for urban sites
Projects with limited landscape opportunities can also use off-site land to earn this credit. They must donate offsite land in perpetuity, equal to 60% of the previously developed area (including the building footprint), to a land trust within the same EPA Level III Ecoregion identified for the project site. The land trust must adhere to the Land Trust Alliance ‘Land Trust Standards and Practices’ 2004 Revision.
Potential conflicts on previously developed sites
If you have a previously developed site, you might have a harder time with this credit if the nature of your project requires you to have a large surface parking area. Previously developed projects that can limit surface parking will have a much easier time.
Also on previously developed sites, using non-native landscaping over a significant portion of a site, such as lush greenery in an arid climate, may present difficulties—with this credit as well as with WEc1: Water Efficient Landscaping.
Greenfield sites can also be a challenge
Meeting the requirements for a greenfield site can be challenging due to the limited range of site disturbance permitted under the credit. The limited buffers allowed for site disturbance may make contractors nervous about this credit because of the large turning radius of construction equipment.
Successful construction and development within these strict parameters is not standard practice—it will require careful mapping of the site to identify allowable areas for disturbance, and staking out construction boundaries to clearly communicate them to all teams working onsite. The contractor has such an important role in executing the credit that making credit compliance a contractual obligation is important.
Buffer requirements eased up
Although still a challenge, the buffer requirements were eased up under a November 2010 LEED addendum. The addendum introduced a new calculation method that could be very useful for teams that are meeting three of the buffer parameters, but having some difficulty with the fourth. See Checklists for more detail.