The LEED Rating Systems

LEED rates all buildings across five major categories of concern, using key environmental attributes in each category. LEED collects and incorporates a wide variety of "best practices" across many disciplines including architecture, engineering, interior design, landscape architecture, and construction. It is a mixture of performance standards (e.g., save 20 percent of the energy use of a typical building) and prescriptive standards (e.g., use paints with less than 50 grams per liter of volatile organic compounds), but leans more toward the performance approach. In other words, LEED believes that best practices are better shown by measuring results (outcomes) not by prescribing efforts alone (inputs).

Each LEED rating system (see Table 2.5) has a different number of total points, so scores can only be compared within each system; however, the method for rewarding achievement is identical, so that a LEED Gold project for New Construction represents in some way the same level of achievement (and degree of difficulty) as a LEED Gold project for Commercial Interiors (tenant improvements). Figure 2.3 shows how the LEED-NC rating system splits points into the five major categories of concern.

TABLE 2.S THE FOUR MAJOR LEED RATING SYSTEMS FOR LARGE BUILDINGS, SPRING 2008

PERCENTAGE PERCENTAGE

TABLE 2.S THE FOUR MAJOR LEED RATING SYSTEMS FOR LARGE BUILDINGS, SPRING 2008

PERCENTAGE PERCENTAGE

RATING SYSTEM

TYPE OF PROJECT

OF TOTAL REGISTRATIONS*

OF TOTAL CERTIFICATIONS

LEED for New

Construction

(LEED-NC)

New buildings and major renovations; housing more than four stories

66.0

74.0

LEED for Commercial Interiors (LEED-CI)

Tenant improvements and remodels that do not involve building shell and structure

10.3

16.3

LEED for Core and Shell

(LEED-CS)

Buildings in which the developer or owner controls less than 50% of tenant improvements

13.7

Buildings

(LEED-EB)

Ongoing building operations, including purchasing policies

10.0

5.2

*Data for LEED registrations and certifications are from the USGBC, furnished to the author, end of March 2008.

*Data for LEED registrations and certifications are from the USGBC, furnished to the author, end of March 2008.

INDOOR ENVIRONMENTAL QUALITY, 23%

MATERIALS & RESOURCES, 20%

INDOOR ENVIRONMENTAL QUALITY, 23%

MATERIALS & RESOURCES, 20%

Figure 2.3 LEED-NC credit distribution.

LEED project attainment levels are rewarded as follows:

Certified >40% of the 64 "core" points in the system Silver >50% of the core points

Gold >60% of the core points

Platinum >80% of the core points

The LEED rating system is a form of an "eco-label" that describes the environmental attributes of the project, similar to the nutrition labels on food. Prior to the advent of LEED, there was no labeling of buildings other than for their energy use, as found in the federal government's ENERGY STAR® program.* Solely presenting a building's energy use compared with all other buildings of the same type in a given region, gives an incomplete picture of a building's overall environmental impact. The LEED scorecard (shown in Fig. 2.4 for the largest LEED Platinum building in the world) shows a project's achievement in each credit category and allows you to quickly assess the sustainable strategies used by the building team.

The irony here is that a $20 million building that is not LEED-certified has less labeling than a $2 box of animal crackers, in terms of its "nutritional" benefits (energy use,

Energy Star program [online], www.energystar.gov, accessed July 31, 2008.

LEED Scorecard

OHSU Center lor Health & Healing

Ves I No I Certified 26 lo 32 pants Silver 33 lo 38 points

55 14 Total Project Score i» Sustainable Sites

2.21.07

Gold 39to51 points

Platinum 52 or more points

Erosion & Sedimentation Control Site Selection

Credit 2 Development Density

I credit 3 Brownfield Redevelopment

J Credit A: Alternative Transportation, Public Transportation Access

Credit 4.2 Alternative Transportation, Bicycle Storage & Changing Rooms

Credit 4.3 Alternative Transportation, Alternative Fuel Refueling Stations

Credit 4.<i Alternative Transportation, Parking Capacity

J Credit 5. Red uced Site DI stu r bance, Protect or Restore Open Space

J credit 5.2 Reduced Site Disturbance, Development Footprint

Credit 6. Stormwater Management, Rate and Quantity

Credit 6.; Stormwater Management Treatment credit 7. Reduce Heat Islands, Not-Roof

[credit 7.2 Reduce Heat Islands, Roof

J credit 8 Light Pollution Reduction

I Water Efficiency

Credit i Water Efficient Landscaping. Reduce by 50%

Credit 1.2 Water Efficient Landscaping. No Potable Use or No irrigation

Credit 2 Innovative Wastewater Technologies

Credit 3,i Water Use Reduction, 20% Reduction

Credit 3.2 Water Use Reduction, 30% Reduction

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Storage & Collection of Recyclables Building Reuse. Maintain 75% of Existing Shell Building Reuse Maintain 100% of Existing Shell Building Reuse. Maintain 100% Stell S 50% Non-Shell Construction Waste Management. Diven 50% Construction Waste Management. Given 75% Resource Reuse, Speciiy 5% Resource Reuse, Spetity 10%

Recycled Content. 5% (POST-CONSUMER + 1/2 POST-IN DUST RIAL) Recycled Content 10% (POST-CONSUMER +1/2 POST-IN DUST RIAL) Regional Materials. 2Q% Manufactured Locally Regional Materials, of 20% Above. 50% Harvested Locally Rapidly Renewable Materials Certified Wood

Indoor Environmental Quality

Minimum IAQ Performance

Environmental Tobacco Smoke (EIS) Control

Carbon Dioxide {CO?) Monitoring increase Ventilation Effectiveness

Construction IAQ Management Plan. During Construction

Construction IAQ Management Plan. Before Occupancy

Low-Emitting Materials, Adhesives & Sealants

Low-Emitting Materials. Paints

Low-Emitting Materials, Carpet

Low-Emitting Materials, Composite Wood

Indoor Chemical & Pollutant Source Control

Controllability of Systems, Perimeter

Controllability of Systems. Non Perimeter

Thermal Comfort, Comply with ASHRAE 55-1992

Thermal Comfort, Permanent Monitoring System

Daylight & Views, Daylight 75% of Spaces

Daylight & Views, Views for 90% of Spaces

BEI Innovation & Desion Process

Crctfti 1 1 innovation in Design: 95% construction waste Cifti.i 1.2 Innovation in Design; 40% Water Savings (jcitn 13 Innovation in Design: 50% Stormwater Capture Credk i 4 Innovation in Design: Exceed MRc4 Crean 2 LEED™ Accredited Professional

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brightworks sus ta inability advisors portland + san francisco + los angeles www. b rig htworks.net

Figure 2.4 Oregon Health and Science University's Center for Health and Healing completed its LEED Platinum certification with a total of 55 points (Platinum requires at least 52), including all 10 Energy Efficiency points and all 5 "Water Efficiency" points. Courtesy of Brightworks.

water use, waste generation, etc.) and its basic ingredients (materials and systems). Owners of commercial and institutional buildings have far less knowledge of what is in the building they just built or bought than you might think, because the construction process is pretty messy; there are usually thousands of design decisions made, along with many product and materials substitutions and changes during construction, and there is seldom money left over to document what really went into the building, so the construction documents often give an incomplete or even inaccurate picture of what's actually there and how all of the building systems are supposed to work together.

To understand a building's ingredients and its expected performance (including operating costs for energy and water), an "eco-label" such as the LEED rating is especially valuable both to building owners and to occupants who may naturally be more concerned about how healthy the building is, rather than how much water it saves.

Complicating this rather straightforward percentage method (for determining levels of LEED certification) is the addition of a sixth category with up to five "bonus" points for "innovation and design process" (see Table 2.2). In addition to securing a certain number of points, each rating system has "prerequisites" that each project must meet, no matter what level of attainment it achieves. For example, a LEED-NC-certified building must reduce energy use at least 14 percent below a comparable building that just meets the ASHRAE 90.1-2004 standard (or 10 percent below the newer ASHRAE 90.1-2007 standard).

Table 2.5 shows the four major systems that account for the vast majority of LEED registered and certified projects as of early 2008, not including the LEED for Homes and LEED for Neighborhood Development pilot programs. From this table, you can see that the LEED-CS system is the second-most popular, followed by LEED-EB. For the purposes of this book, we're only going to focus on LEED-NC and LEED-CS, which represent about 80 percent of all LEED registered and certified projects to date.

To best understand LEED, it helps to think of it as a self-assessed, third-party verified rating system. In the case of a LEED certification, a project team estimates the particular credits for which a project qualifies and submits its documentation to the USGBC, which assigns the review to an independent third party. The reviewer has three choices with each point:

1 Agree with you and award the point claimed.

2 Disagree and disallow the point.

3 Ask for further information or clarification.

To resolve differences of opinion, there is a one-step appeal process. LEED FOR NEW CONSTRUCTION

The most widely known and used LEED system is LEED-NC, which is useful for all new buildings (except core and shell developments), major renovations and housing of four stories and above. Table 2.2 captures the essence of the LEED-NC rating system's major issues. Through the end of 2007, about 68 percent of LEED projects were registered and 74 percent were certified under the LEED-NC assessment method. LEED-NC can also be used for projects on college and corporate campuses and for schools, in which common systems (e.g., parking, transportation, and utilities) often supply a number of buildings.

A LEED-NC rating is typically awarded after a building is completed and occupied, since it requires a final checkout process known as "building commissioning" before the award can be made. Under the current LEED version 2.2, certain credits known as "design phase" credits can be assessed at the end of design and prior to construction, but no final certification is made until all credits are reviewed after substantial completion of the project.

LEED FOR CORE AND SHELL BUILDINGS

LEED for Core and Shell is a system employed typically by speculative developers who control less than 50 percent of a building's tenant improvements at the time on construction. They may build out 40 percent of the space for a lead tenant, for example, and then rent the rest of the building to several tenants who will take much smaller spaces. LEED-CS allows a developer to "pre-certify" a design at a certain level of attainment, then use the LEED rating to attract tenants and, in some cases, financing. Once the building is finished, the developer submits documentation to secure a final LEED rating. Figure 2.5 shows how the LEED credits in the five main categories are distributed in the LEED-CS system. Except for having eight fewer total points (including two fewer points for energy efficiency), the distribution of credits is quite similar to LEED-NC.

INDOOR ENVIRONMENTAL QUALITY, 20%

MATERIALS & RESOURCES, 20%

INDOOR ENVIRONMENTAL QUALITY, 20%

MATERIALS & RESOURCES, 20%

Figure 2.5 LEED-CS credit distribution.

The benefit of the LEED-CS system for a commercial developer is that marketing cannot wait until a building is finished. By allowing a pre-certification using a system very similar to LEED-NC, the LEED-CS rating assists the developer in securing tenants and sometimes financing, and thereby encourages more green buildings. Not only that, LEED-CS awards a point for creating tenant guidelines that encourage each tenant to use the LEED-CI system to build out their interior spaces. If that happens, the result is similar to a LEED for New Construction building, and everyone is happy!

PLATINUM PROJECT PROFILE

Signature Centre, Denver, Colorado

Designed, developed, managed and built by Aardex, LLC, the Signature Centre is a 186,000-square-feet, five-story, class AA speculative office property. The total project cost, including land, finance, and soft costs, was less than $220 per square foot. The Signature Centre was designed to reduce total energy use by a minimum of 36 percent. Indoor water use is estimated to be 40 percent less than a similar conventional building. The building's underfloor air system not only improves indoor air quality and reduces absenteeism, but it also reduces utility costs by 30 percent. The project materials include 20 percent recycled-content materials, 50 percent FSC-certified wood and 20 percent locally sourced materials.*

Courtesy of Aardex, LLC.

*John Trojan, "We Want to Raise the Bar," Business Leader Magazine, October 2007, pp 21-27.

There is growing evidence that a LEED-CS certification helps developers to lease space faster and attract better tenants. There is also evidence that ENERGY STAR buildings attract higher rents and result in higher resale values.* In Atlanta, Hines certified their 1180 Peachtree building as LEED-CS Gold.t Both the Hines' LEED-Silver One South Dearborn in Chicago and the 1180 Peachtree building were sold in 2006 after completion of construction and leasing activity. Jerry Lea of Hines comments about the benefits of the LEED rating system: "Both buildings got the highest sales price (dollars per square foot) for buildings ever sold in those two markets. Is it because they were green? I think there is some correlation that green buildings help you lease the space, and that helps sell them."*

LEED FOR COMMERCIAL INTERIORS

LEED-CI is designed mainly for situations in which the base building systems are not changed and which a tenant only takes up a few floors in a much larger building. In this circumstance, the ability to affect total energy and water use, or such issues as open space, landscaping or stormwater management is either much smaller or nonexistent. Thus, other green building measures are incorporated into the evaluation system. These measures include choices that tenants can make about lighting design, energy-using equipment, lighting control systems, submetering, furniture and furnishings, paints, carpet, composite wood products, and length of tenancy.

Because the focus of this book is on the use of integrated design process (IDP) in new building construction, I'm not going to focus much attention on LEED-CI. This is not meant to slight the many fine LEED-CI projects, but the fact is that most tenant improvements happen so fast, there is not time for a conventional IDP.

LEED FOR EXISTING BUILDINGS

LEED-EB was originally proposed and designed to be a method for assuring on-going accountability of LEED-NC buildings over time. It has become instead a stand-alone rating system for building owners who want to benchmark their operations against a nationally recognized standard. LEED-EB addresses many issues not dealt with in new construction, including upgrades, operations and maintenance practices, environmentally preferable purchasing policies, waste management programs, green housekeeping, continuous monitoring of energy use, retrofitting water fixtures to cut use, relamping, and a host of other measures. By early 2008, seven projects had received LEED-EB Platinum ratings, and the system appeared to be gaining momentum, as new LEED-EB project registrations in 2007 almost tripled the number of such undertakings underway in the United States. Again, similar to LEED-CI, we're not going to

*See "Does Green Pay Off?" by Professor Norman Miller, www.green-technology.org/green_technology_magazine/ norm_miller.htm, accessed July 31, 2008.

twww.hines.com/property/detail.aspx?id=507, accessed March 20, 2007. Jerry Lea, Hines, Interview, March 2006.

Figure 2.6 The William J. Clinton Presidential Library and Museum in Little Rock, Arkansas received a LEED-NC Silver certification and later, after some additional improvements, earned a LEED-EB Platinum certification. ©Photography by Timothy Hursley.

devote any time in this book to LEED-EB, because it simply doesn't require an IDP in the same way as new buildings. Figure 2.6 shows the Clinton Presidential Library and Museum originally certified under LEED-NC, then re-certified under LEED-EB.

Homeowners Guide To Landscaping

Homeowners Guide To Landscaping

How would you like to save a ton of money and increase the value of your home by as much as thirty percent! If your homes landscape is designed properly it will be a source of enjoyment for your entire family, it will enhance your community and add to the resale value of your property. Landscape design involves much more than placing trees, shrubs and other plants on the property. It is an art which deals with conscious arrangement or organization of outdoor space for human satisfaction and enjoyment.

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