This article originally appeared in the September/October issue of ARCHITECTURAL LIGHTING magazine.

In the first part of this article, which appeared in the July/August 2010 issue, we discussed energy codes in the United States and how they are interacting with lighting. Now we turn our attention to green standards and building codes and their contribution to shaping lighting design. We will examine the most well-known green building standard in the United States, the Leadership in Energy and Environmental Design (LEED) rating systems, developed by the U.S. Green Building Council (USGBC), and then the new green building codes that are aiming to transform sustainability objectives into mandatory, enforceable code.


The USGBC's rating systems have become widely used and influences standards for the design, construction, and operation of buildings. Because LEED is relatively new (first introduced in 1999) and has grown in popularity extremely fast, the process of developing new versions is still evolving. This is not as structured nor as open as the development of energy codes, and because LEED is voluntary, instead of a legal code or ANSI standard, the USGBC is not obliged to follow an open and structured process. (But they are moving in that direction.)

The current version is LEED-2009, and LEED-2012 is in development. Informal groups of Subject Matter Experts (SMEs) led by LEED Technical Advisory Groups were appointed by USGBC staff to work on revisions to each credit for LEED 2012. Lighting-related LEED credits range across three different categories: Energy, Indoor Environmental Quality, and Sustainable Sites. Members of the International Association of Lighting Designers (IALD) serve as SMEs for Indoor Environmental Quality (daylighting and lighting controls for occupant comfort) and Sustainable Sites (light pollution control).

The LEED-2012 Public Review Draft is expected to be published for public comment in September, and USGBC responses to these comments will be published thereafter. If the USGBC follows its previous procedure, comments that are deemed to be an improvement will be incorporated into a new draft and other comments rejected, but without any formal dialog with commenters. The final draft of the new version of the rating systems will be voted on by USGBC member organizations, with a target release date of January 2012.

The public review draft of LEED-2012 will provide an indication of what the next version will look like. The credit that addresses light pollution control will be significantly revised to resolve some of the quirks that can prevent very sensitive designs from meeting the requirements. It also will likely adopt the BUG (backlight, uplight, and glare) system developed for the International Dark-Sky Association (IDA) and Illuminating Engineering Society (IES) Model Lighting Ordinance (MLO).


But what exactly is a green building code? Imagine all the categories in LEED—site sustainability, water use, energy, indoor environmental quality, materials and resources—but written in enforceable code language. This would be a mandatory code, not an optional points-based rating system.

To meet goals for greenhouse gas reduction and sustainability, many cities want a green building standard that they can use as an enforceable code for commercial development. A few cities, such as Boston, Dallas, and Los Angeles, have adopted legal requirements for some equivalence of LEED certification, but not actual LEED certification. Codes, which are legal enforceable regulations, need to be unambiguous and enforceable—you either comply or you don't.

Because LEED is a points-based system in which you can choose what you do to earn points, a LEED building can be many different things. Official LEED certification requires the payment of significant certification fees to a third party and is dependent on the decisions of that third party—something that may be inappropriate and legally questionable for a government to require. For these reasons, LEED does not make a good code and should be not used as one. Because of this, the USGBC has supported the development of green building codes. It envisions the green building codes as the baseline code minimum for building performance, with LEED forging ahead as the voluntary “beyond code” program pushing the envelope of sustainable design. Two green building codes have been in development: Standard 189.1 from ASHRAE, the IES, and the USGBC; and the International Green Construction Code (IGCC) from the International Code Council (ICC) and the American Institute of Architects (AIA). The IALD, along with many other design and construction industry representatives, is participating in the development of both.

Standard 189.1 was published this January after several years of development and four public-review drafts. It is available for adoption and has gone into continuous maintenance status, similar to other ASHRAE standards.

A drafting committee began work on the IGCC in the summer of 2009. The first draft for public review was released in March, and has entered into a code development process similar to that for the International Energy Conservation Code and other ICC codes. The first edition, IGCC-2012 is expected to be published in March 2012. (According to the ICC, though, the current public review draft is available for adoption.)

So, coming into this spring, it appeared as though we were going to have two competing green building codes, and this caused quite a bit of consternation. Fortunately, the ICC and ASHRAE realized that competing codes were not in their best interest, nor in the best interests of the design, construction, and code-enforcement communities. In March, they announced a reconciliation. Both codes will continue their independent development processes, but 189.1 will be available as a “jurisdictional option” in the IGCC. This means that a jurisdiction will be able to decide to adopt 189.1 as their green building code instead of the IGCC, and will need to decide which to require at the time of code adoption. The design team will have to adhere to the selected code.


So which code will be adopted? Since the IGCC is produced by the ICC—the source that code officials turn to—it will carry a lot of weight, and it seems to be gaining momentum because of a strong marketing push from the ICC. In June, the U.S. Conference of Mayors passed a resolution endorsing the IGCC and urged local governments to adopt it. With this attention, will anyone adopt 189.1, even though it has already been published? Once IGCC-2012 is published, will there be any reason for a jurisdiction to choose 189.1 instead of IGCC? Of course, these questions are hard to answer since we do not yet know what the final IGCC will look like.

Assuming that the IGCC becomes the prevalent green building code, what will the lighting related provisions look like? Here are some things to expect:

  • Light pollution control using IES TM-15 BUG ratings.
  • Auto demand-reduction technology requirements.
  • New requirements for automatic controls for lighting, signage, and plug loads.
  • Verification and commissioning.
  • Energy monitoring.
  • Mandatory daylight in many building types, with exact requirements varying based on climate.

Two new ideas in the IGCC are Jurisdictional Requirements and Project Electives. Jurisdictional Requirements are a list of provisions that the adopting authority can choose to include in the code as mandatory requirements. For example, control of light pollution is currently one of these provisions. Project Electives are a separate menu of provisions that the design team can choose from, and will have to comply with, in addition to the main mandatory provisions of the code. They will have to comply with a set minimum number of electives from this list, but they can choose which ones; the minimum number of required electives will be set by the jurisdiction at time of adoption. These two aspects of the IGCC allow the local jurisdiction to tune the code to meet its needs and conditions, and to adjust the stringency.
Assuming the IGCC becomes the green code of choice, how widely and how quickly will it be adopted? No one knows for sure. But if it is widely adopted, building design and construction professionals will have to become conversant in the IGCC, energy codes, and LEED. And they will need to know which version of the IGCC (2012, 2015, etc.) has been adopted by the jurisdiction, and also which Jurisdictional Requirements have been adopted.


Another thing to think about is the relationship between green building codes and energy codes. The energy provisions of the green building codes are designed to overlay the energy code and to make the standards more stringent. But what happens if a state adopts an energy code that is more stringent than the energy provisions of the green building code? This could get very confusing for designers.

If your head isn't already hurting, try this: Say you are designing the lighting for a LEED project in a locality that has adopted a green building code. You will have to design to two different green standards, every design option will have to be tested twice, and two sets of calculations and documents will need to be produced to prove compliance with each provision in both. I hope the USGBC and the ICC are thinking about this.

If green building codes are widely adopted, we design professionals will have our work cut out for us. Not only will we have a responsibility to design to the green building code, but we will also need to understand that code's relationship to energy codes, LEED, and other codes such as the MLO.

Glenn Heinmiller, IALD, is a principal at the architectural lighting design firm Lam Partners, based in Cambridge, Mass., and is the chair of the energy and sustainability committee of the International Association of Lighting Designers.

This article originally appeared in the September/October issue of ARCHITECTURAL LIGHTING magazine. Part one of the Rubik Code series appeared in the July/August issue of ARCHITECTURAL LIGHTING.