Although the latest incarnation of the U.S. Green Building Council’s LEED rating system has been around for almost a year, projects have still be able to enjoy the more familiar likeness of LEED 2009. However, the window of time for the grace period of the system transition continues to close with all new projects needing to apply for LEED v4 after June 2015. As designers and engineers begin to focus more on the effects of the imminent change ahead, it begs the question as to whether or not the system is simply changing or actually improving.
The LEED rating system has been the most prevalent metric of its kind in trying to create a higher standard of sustainability for the built environment. I have written before (here) about why I think LEED has been a valuable system that should continue to be used, but even proponents agree that it is an imperfect system. There are a number of aspects that make the most recent version of LEED not only hot off the racks, but a system that is evolving productively with each iteration as a process of continual refinement.
An Evolving System
Without a doubt, the keymasters did not start from scratch. LEED v4 is still a system consisting of 100 points spread over a group of categories meant to target different aspects of building siting, design, construction and operation. There are still four levels of achievement from “Certified” all the way to the coveted “Platinum.”
Perhaps to the chagrin of those who are interested in having the green label more than actually having a green building (as we see in some businesses) the new LEED will not make that easier. On the contrary, the consensus is that the new point structure is holistically more difficult to achieve as the criteria is ratcheted up–which is a good thing. Some experts say that design criteria to earn a “Gold” rating in former LEED versions may only merit “Silver” in the new Version 4.
More prerequisites were added to point categories to raise the standard of buildings even with the base level of certification. Claiming to be a more “integrative” process, Version 4 now guides design teams to using a preliminary energy model of the building at its schematic phase in order to identify opportunities for reducing both energy and water use. In states that are inserting sustainability criteria into their building codes this is already becoming a requirement for permit filing anyway–and rightly so. Incorporating an energy model at the beginning of the process forces the design team to recognize the large sources of energy use up front while the design is at its most pliable state.
The baseline also lifted in energy targets with v4 incorporating the 2010 version of ASHRAE 90.1 that identifies an energy standard for buildings outside of low-rise residential. (ASHRAE stands for American Society of Heating, Refrigerating and Air-Conditioning Engineers which is charged with creating and refining standards for building systems). This integration inherently raises the baseline over most codes in the U.S. with few states or municipalities having yet adopted the 2010 version of the common standard.
The new system also requires things like energy metering that provide feedback over time after the building is completed–beginning to address one of LEED’s most common criticisms of failing to measure whether a building’s functional performance matches the criteria laid out in the design phase. While LEED used to only require commissioning of the building at its completion (a formal review by a 3rd party to confirm that systems were built to design specifications) it now also requires verification that the resource use over time lives up to the goals. At the same time, it is important to remember that sustainability and the effectiveness of LEED cannot only be tied to energy use (as in the case here).
Another new feature in the energy category is a credit targeting Demand Response. As our grid continues to evolve, utility companies organize contracts with building owners that allow them to decrease the amount of power provided to them when the grid is stressed in exchange for better rates. This allows utilities to help smooth the peak of demand, usually in the middle of the day, as necessary and avoid the demand surging past available supply, creating brownouts. Support for demand response programs could help promote the installation of more onsite energy production and storage (like in buildings such as One Bryant Park) that will not only make the grid more pliable, but theoretically help avoid peak price spikes and keep power prices lower. With the goal of eventually getting to an electrical grid that is a bit “smarter”, it is great to see a system like LEED playing a proactive role in trying to push progress from the opposite end.
So far, the most contentious addition to LEED is the integration of Environmental Product Declaration or EPDs. All three types of EPDs serve as a something similar to a nutritional ingredient list for products or services. They outline the components and energy used in making products to give a more holistic picture of their potential effect on the biosphere.
The purpose of EPDs in the general marketplace was to increase the transparency for consumers, but their reaction has been mixed. Conflicts have arisen in states like Ohio where corporate lobbying efforts have objected to the inclusion of EPDs as restrictive or prejudice against specific products–a strange argument unless of course the information released in an EPD would be less than flattering to the product, in which case maybe it’s information we, as consumers, should have anyway? While the integration of EPDs has the potential to rock the boat for the marketplace of building components, it seems unlikely that their inclusion would risk making the quality of space worse for building occupants or increase negative effects on the biosphere.
One of the more surprising changes made by the USGBC was one of the most subtle. Over its life, LEED had grown to be known by some as a “checklist” that project team members could simply mark off in order to reach certain levels of certification. The criticism has been that the image of achievement could be bought and tallied rather than proactively designed. One of the USGBC’s responses was to remove the credit numbers from the system, relying only on the underlying text to describe each potential credit. The thought was (and I tend to agree) that the numbers brought it closer to a document that could be “checked” off on a spreadsheet. Though a minor change, it shows that the caretakers of the process give importance to how the system is perceived and used.
LEED v4 stands as another bright spot in a lineage of positive (albeit imperfect) impact, serving as evidence that the creators of the system continue to be engaged in the task of how to work towards a very difficult goal in a field entrenched in the economic and cultural inertia of the status quo.
Any natural ecosystem operates in a state of dynamic equilibrium that responds to the combination of internal and external forces exerted upon its various components–a push and pull around a point of balance. It is this dynamism that promote evolution over time, keeping participants relevant rather than extinct. The evolution of the LEED system operates the same way in the very complex ecosystem of the many forces that contribute to crafting the built environment with LEED itself being a force of its own to promote the evolution of those around it. If the goal is sustainable buildings with healthier occupants, the standard is certainly not there yet, but LEED is helping to guide us in the right direction.