By Kevin Brooks
Part two in a two part series
In Part two, we’ll look at how the Living Building Challenge differs from LEED, as well as the necessary requirements for the Living Building Challenge.
How It Differs From LEED
As compared to LEED’s five core categories (sustainable sites, water efficiency, energy and atmosphere, materials and resources, and indoor environmental quality), the Living Building Challenge has seven categories, known as “petals:” site, water, energy, health, materials, equity, and beauty. The petal reference comes from the vision that the built environment can be “designed and constructed to function as elegantly and efficiently as a flower.” While there are obvious similarities between the order and grouping of the LEED categories and the Living Building Challenge’s petals, the Living Building Challenge rating system also delves into areas that LEED has yet to really touch, mainly the equity category, which is intended to address universal access and social justice issues to advocate for stronger communities. In addition, while there are nine different LEED rating systems, the Living Building Challenge’s four applications (known as typologies) are somewhat more basic. These include new buildings, renovations, landscape or infrastructure projects (with no conditioned spaces), and neighborhoods (a continuous development with multiple buildings).
The Living Building Challenge is currently on Version 2.0 and has not yet seen the same number of iterations in the program’s development as LEED. While certification under the LEED 2009 100-point rating system is based not only on the number of points achieved – from 40 (certified level) to 80 and above (platinum level) – but also on a series of mandatory prerequisites and optional credits, the Living Building Challenge has mandatory requirements, known as imperatives, assigned to each of the four different typologies. Generally, these consist of 20 standard mandatory requirements, significantly less than the combined mandatory prerequisite and optional credit total of the different LEED rating systems.
Another difference between LEED and the Living Building Challenge is that while LEED allows modeling of a building’s energy usage, certification under the Living Building Challenge requires 12 consecutive months of actual performance data.
Living Building Challenge Requirements
As noted, the Living Building Challenge generally takes today’s standard measures of green building and sustainability as accepted common place and raises the bar to demand performance in excess of what is considered green or sustainable. Under the Living Building Challenge, development is limited to previously developed sites and development on or adjacent to sensitive ecological habitats is prohibited. In addition, a one-to-one habitat offset must be established corresponding to the acreage being developed.
Each project must also integrate the development of on-site acreage for agricultural purposes based on the project’s floor area ratio metrics. In addition to a requirement that every occupied space include operable windows for access to fresh air and daylight, the Living Building Challenge’s certification requirements also incorporate the concept of biophilia into the project’s design. In short, biophilia is the mimicking of nature in the built environment, whether in the incorporation of environmental features, natural shapes and forms, or natural patterns and processes.
The Living Building Challenge’s materials petal includes a “red list” – a list of materials and chemicals that are prohibited in any the project’s components and materials. Among other things, this list includes PVC and certain wood and flame retardant treatments, as well as a variety of organic compounds and heavy metals. Certification also requires that the project offset its carbon footprint; this includes not only the carbon footprint resulting from the initial construction but also from its ultimate replacement.
Certification also includes a general requirement for third party certification of fair labor practices and sustainable resource extraction standards. Where this certification doesn’t currently exist, the project team is responsible for taking on an advocacy role to promote the development of such practices and standards.
Finally, the Living Building Challenge also requires the local and regional sourcing of materials – the allowable distance from the project site to the materials to be utilized is correlated to the material type. Heavy and/or dense materials have a shorter allowable travel distance than lighter ones, and such travel limitations also apply to services rendered in association with the project. As with other green building certifications, the Living Building Challenge has evolved out of the USGBC’s LEED rating system. While the number of projects currently enrolled in the Living Building Challenge is significantly fewer than in the LEED program, the project list does continue to grow. Much like the premiere of LEED, the Living Building Challenge is advancing the development of green technologies and applications, as well as holistic sustainability.
At the end of the day, this is a good thing and we, as construction practitioners, must be prepared to add the other green building certification programs such as the Living Building Challenge to our toolbox.
For more information on the Living Building Challange, please visit the International Living Future Institute Website at http://ilbi.org
Click here to read Part I of this series