Patrice and I have been getting calls and emails from around the country asking for help in understanding the draft version of LEED v3 2009 currently out on the street for public comment. We're sorry for not getting this out sooner, but with our crazy schedules it took us a month to sit down with our colleagues at USGBC to review the final draft that went out on May 19th. And NO, you're not going crazy, some of the most significant changes we've reported in this blog do not show up in it, yet. But don't despair, there's a perfectly good reason why and below we will describe in detail what is happening.
LEED v3 2009 Draft Overview
So, if you have had the opportunity to look at the draft LEED v3 2009 documents, then you've seen some of the changes but may be wanting more. First, we'll give you a briefing on some of the significant changes and then we will describe what you can't see yet but is in the works. (Warning! This is a long and fairly technical posting!)
The U.S. Green Building Council has provided drafts for 5 products: NC (New Construction & major Rehabs), Core & Shell, CI (Commercial Interiors), Schools and EB (Existing Buildings - which is for maintenance and operations NOT rehabs of historic/existing buildings). We are specifically discussing the changes to NC since that is the most commonly used product for large Rehabilitation projects, although Core & Shell is sometimes used as well. Here are some highlights of some of the major changes:
The credits are now weighted according to Life Cycle Analysis criteria (LCA) . And by applying LCA to the existing credits the total score for a project has been increased from 69 to 100 points (although actually 110 since there are various bonus points). The workbooks used to come up with the new weighting are provided as Supporting Documents under the Weightings Tool on the USGBC website.
- The 6 divisions remain the same, but the points have been reallocated according to the results of the LCA weighting. Sustainable Sites has gone from 14 possible points to 26. Water Efficiency has increased from 5 possible points to 10. Energy & Atmosphere has increased from 17 possible points to 35. Materials & Resources has increased from 13 possible points to 14. Indoor Environmental Quality has remained at 15 possible points. Innovation & Design has increased from 5 possible points to 6. And a New Section of Regional Bonus Credits with 4 possible points has been added.
- Sustainable Sites: Some of the biggest changes to LEED are found here and the increases in these points are directly related to one of the issues we talk about all the time - "green sprawl". The increase of Credit 2 - Development Density & Community Connectivity encourages the construction or renovation of buildings within a dense community - and this credit has increased from 1 to 5 credits. We applaud this improvement. We've all heard about the building that's been constructed in the suburban fringe going for LEED platinum. This helps to dissuade that kind of activity.
- The next biggest change in the Sustainable Sites division is in Credit 4.1 - Alternative Transportation - Public Transportation Access which has been increased from 1 point to 6 points. Again encouraging the placement of buildings in dense communities with access to various forms of public transportation .
- Water Efficiency: This division is now more effectively addressing the topic of water use in our buildings. We hear all the time about carbon footprints and energy efficiency, but many scientists believe that the overuse of water may have an even more significant impact on our way of life in the very near future. There is now a prerequisite in this division for a 20% reduction of water use of the baseline for the building type. Every other credit has been doubled from 1 point to 2.
- Energy & Atmosphere: With an increase from 17 to 35 possible points, and an addition of 9 possible points to Credit 1 - Optimize energy performance, this is where one of the biggest impacts can be made. And this doesn't mean you need really complicated systems and technology. I saw a presentation last week about a Gold certified rehab project in Baltimore that also received tax credits and received all 10 points from this credit using a very low tech approach.
- Materials & Resources: This is the division that is causing a lot of consternation in the preservation community because at first glance, Credits 1.1 and 1.2 don't appear to have changed significantly. Credit 1.1 (Building Reuse, Maintain 75% of Existing Walls, Floors and Roofs) has increased from 1 to 2 points. In addition, in Credit 1.2 if you maintain 95%, you can get an additional point for a total of 3 points (this remains the same from 2.2). Does this seem too little? Well that's because there is an entirely separate Compliance Path that is still in development using the durability of the building materials as the metric. Read about this below.
- Indoor Environmental Quality: This division has basically remained the same.
- Innovation & Regional Bonus Credits: The USGBC Chapters are being given the responsibility to develop 4 additional points under the Innovation & Design Process division to increase the value of pursuing credits that address environmental areas of concern in a project's region. This is also a positive change which can benefit many traditional buildings which were often designed with an understanding that their siting was specific to their climate.
- Should we expect more changes? Yes, and soon. It was a daunting task for USGBC to revise LEED even this much in less than a year. It is now on the road to becoming a much more scientific approach. Can it improve? Well of course and LCA is still really in its infancy. But USGBC did not want to change their products so drastically in one year to upset the entire market. The intention is that the next revision, targeted for 2010, will actually change some of the credits, removing some and adding others.
Alternate Compliance Path for Existing Buildings
Okay, so this is what is missing in the current draft on the street - a completely new Alternate Compliance Path that will benefit Existing Buildings and will be entitled "Life Cycle Assessment of Building Assemblies." This will be an optional path to use the Materials & Resource Credits by addressing the durability and embodied energy of existing materials by using LCA for assemblies. Life Cycle Assessment is a scientific methodology to assess the environmental performance of a product over its full life cycle. But the science is young and there are many different approaches to it. USGBC has an LCA working group comprised of the most experienced LCA scientists on the continent. And just as they were getting ready to put LEED v3 2009 out for public comment, it was decided that this Alternate Compliance Path still needed some work because it is so groundbreaking and they are developing a special LCA Credit Calculator that quantifies the life cycle impact of various materials and building assemblies.
Since it is still being finalized we are not at liberty to discuss the details of the draft, but it is likely that up to 3-5 additional points can be attributed to existing assemblies. Don't quote us on that - this is just an example while it is being finalized. We are very, very supportive of this approach. The intent of this path is to encourage environmentally preferable building materials and assemblies. New construction can also use this path, however, from our first review of it, existing buildings would rank the highest and achieve the most points.
This Alternate Compliance Path will also be ready for use with LEED v3 2009 in early 2009. Currently the intent is that any building already registered for LEED will be able to use the Alternate Compliance Path - even if your project is registered under one of the past versions such as NC 2.2. We are delighted to announce that we have volunteered one of our projects - the Visitor Education Center at Lincoln Cottage in Washington, DC which is registered under LEED NC 2.2 and is on target for LEED Gold - to be a pilot project for the Alternate Compliance Path.
We will be working with USGBC to further incorporate more social and cultural metrics into the next LEED revision - these are the unquantifiable metrics such as social sustainability and social capital. See my blog posting from December 19th which further describes these. We are planning a retreat with USGBC and other partners in the fall to flesh this out.
Embodied Energy - it's not the Silver Bullet
A lot of people would like to believe that the concept of embodied energy is the most significant reason that "the greenest building is the one that's already been built." And as a result we have people anecdotally arguing that an existing building should get 15 points or more in the LEED system (in MR Credit 1.1) because of that. But we want to remind everyone about this basic fact represented in the pie chart from the Athena Institute. Over the life of a building, typically about 75% of the energy use is from operating energy, while about 15% is from embodied energy and 10% from recurring embodied energy (the energy used to renovate a building). This is why the early rating systems have focused on improving the operating energy use of buildings and not significantly addressed the embodied energy. And if you look at the assignment of points in the new 100 point LEED system, at just about 15% of the points, Materials & Resources appears to be right on target.
Should you Comment on LEED v3 2009?
We have been encouraging everyone to read and comment on LEED v3 2009. Given the fact that the Alternate Compliance Path isn't officially out for public comment, we are not overly concerned now about ensuring that everyone comments. We're not dissuading you from commenting and certainly until you see the final text for yourself, you just have our assurances that we are encouraged that this Alternate Compliance Path is a really terrific start at the better integration of preservation metrics into LEED. If you want to comment on other apsects of LEED v3 2009, remember comments are due by 5pm June 22nd.
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