Green buildings standard

• Photo courtesy of The Garland Co. Inc., Cleveland.

Another acronym has been introduced to the roofing industry—LEED. No, this is not a new membrane type. The Leadership in Energy & Environmental Design (LEED) Green Building Rating System™ is a voluntary, consensus-based standard for developing high-performance, sustainable buildings. Launched four years ago by the U.S. Green Building Council (USGBC), LEED is an integrated design approach that addresses the potentials of water conservation, energy efficiency, renewable energy, material selection and indoor environmental quality. Buildings that successfully meet LEED requirements can receive certification and qualify for tax credits.

Although LEED only recently was introduced, more than 700 private and public buildings have been registered for LEED certification. About 39 percent are state and local government projects; 39 percent are private-sector projects; 13 percent are nonprofit projects; and 10 percent are federal projects. Projects include manufacturing facilities, firehouses, convention centers and schools. Projects have been registered from all 50 U.S. states and nine countries.

The pace of LEED certification undoubtedly will quicken as a growing number of state and local governments encourage sustainable building practices through various financial, zoning and other regulatory incentives.

Following is an overview of LEED; issues related to roof systems; and items of interest to roof system designers, manufacturers and roofing contractors.

Certification

USGBC is a coalition of more than 3,000 corporations, builders, universities, federal and local agencies, and nonprofit organizations that work to promote buildings that are environmentally responsible, profitable, and healthy places to live and work. LEED standards currently are available for new construction and major renovation projects, existing building operations and commercial interior projects. But new standards are being developed, including a standard for existing buildings. Commercial buildings, including offices; retail and service establishments; institutional buildings (schools, museums and churches); hotels; and residential buildings of four or more habitable stories, are eligible for certification.

The first step to certify a building is to register the project during the early phase of project design. After registering a project, a design team prepares documentation and calculations to satisfy LEED prerequisites and credit submittal requirements. There is an initial registration fee and certification fee; fees are based on buildings' sizes.

Why go through the certification process? Certification validates compliance with the LEED Green Building Rating System through a third-party review process. Also, certification may be required to qualify for a growing array of state and local government incentives.

For example, Maryland, New York and Oregon offer tax credits for LEED-certified buildings. Also, the U.S. General Services Administration, a central management agency in the federal government, has required LEED certification for all its buildings since fiscal year 2003.

Roof system credits

A variety of credits specifically pertaining to roof systems can be earned. In addition, roof systems used with other building components or aspects can earn credits. Credits also can be earned by voluntarily meeting or exceeding each credit's technical requirements. Credit points add up to a final score that relates to one of four levels of certification: Certified, Silver, Gold and Platinum (from the lowest level to the highest level). Following are ways roof systems can earn credit points (the information is from LEED Rating System, Version 2.0):

• Stormwater Management section. Specifying a green roof system earns one point. Green roof systems earn one stormwater-management point because they do not rapidly release rainwater into storm-drainage systems.
  
  
• Heat Islands section. Specifying a green roof system for at least 50 percent of a building's roof area earns one point. A point also can be earned by specifying an ENERGY STAR®-compliant roof provided that it has an emissivity of at least 0.9. (Note: The emissivity requirement, which is not an ENERGY STAR requirement, precludes the use of aluminum-pigmented coatings and bare metal panels.)
  
  
• Minimum Energy Performance section. Compliance with ASHRAE Standard 90.1, "Energy Efficient Design of New Buildings Except Low-Rise Residential Buildings," or the local energy code (whichever is more stringent) is required. This requirement pertains to roof systems and other building systems. One point to 10 points can be earned by achieving increased levels of energy performance.
  
  
• Renewable Energy section. If at least 5 percent of a building's total energy use is provided through the use of on-site renewable energy systems, one point can be earned. For example, solar energy panels could be mounted on a roof system.
  
  
• Building Reuse section. One point can be earned by maintaining at least 75 percent of an existing structure and "shell"; roof coverings are not included in this provision. Roof coverings can be upgraded to achieve enhanced thermal performances and provide other LEED-approved points.
  
  
• Construction Waste Management section. One point can be earned by diverting at least 50 percent of construction, demolition and land-clearing debris from landfill disposal. Diversion is accomplished by recycling or salvaging. Therefore, roofing-related activities could be combined with other construction elements to achieve this goal.
  
  For example, with an existing building that has a ballasted roof system, the ballast could be removed and reused on a new roof system. Another example is a European insulation manufacturer that provides roofing contractors with large bags to collect scrap insulation. The mineral wool scraps are taken to the manufacturing plant and used in the production of new insulation boards.
  
  
• Resource Reuse section. One point can be earned by using salvaged materials for at least 5 percent of a building's materials. Materials from other reroofing projects, such as ballast or extruded polystyrene insulation, could be used on a new building.
  
  
• Recycled Content section. One point can be earned for using enough products that incorporate a minimum amount of recycled material. Perlite roof insulation uses enough recycled material to qualify. Gypsum roof board made from synthetic gypsum also qualifies.
  
  
• Regional Materials section. One point can be earned if a minimum of 20 percent of a building's materials are manufactured within a radius of 500 miles (800 km) of the building site. For many building sites, a variety of roofing products are made within 500 miles (800 km). If a minimum of 50 percent of a building's materials are manufactured within 500 miles (800 km) of a job site, an additional point can be earned. Using materials that are manufactured relatively close to a building site saves energy that would otherwise be consumed by transporting the materials a greater distance.
  
  
• Innovative and Design Process section. One point to four points can be earned for exceptional performance above LEED requirements. LEED gives life-cycle analysis of material choices as an example. Although not specifically cited, design of a durable roof system that has a high probability of providing a long service life or lends much of itself to reuse in the future (such as a protected membrane system where the ballast and insulation could be reused) could qualify for these points.

Manufacturers

USGBC encourages manufacturers to compare the performances and attributes of their products to the requirements outlined in LEED Rating System, Version 2.0 and its documentation requirements to identify the credits that relate to their products. This information then can be communicated to building designers and roofing contractors.

However, manufacturers need to be aware that products cannot be LEED-certified. Certification only applies to a complete building, not individual products. Likewise, the LEED logo cannot be used on green building products. Manufacturers that are members of USGBC can use the USGBC member logo.

As manufacturers become more aware of LEED, marketing literature likely will indicate how various roofing products can help earn LEED points.

Roofing contractors

LEED probably will affect roofing contractors in at least a couple of ways. For architectural firms trying to achieve Gold or Platinum LEED ratings for buildings, I envision closely collaborating with roofing contractors and other subcontractors as they strive to obtain as many points as reasonably possible.

For example, a roofing contractor could help an architect by advising what roofing material types are made within a 500-mile (800-km) radius of a building site and what materials meet the desired recycled content. A contractor also could assist in the innovative design category.

I also envision more office work for roofing contractors. As part of the LEED-certification process, designers are required to submit substantial documentation to demonstrate compliance with LEED requirements. Contractors will need to furnish some documentation to designers.

For example, if a contractor claims roof insulation and membranes are manufactured within 500 miles (800 km) of a building site, he likely will be required to obtain a letter from the manufacturer stating this fact. Similarly, if a contractor supplies recycled ballast from another roof system, he probably will need to furnish documentation.

Specifications prepared by architects who have experience with LEED projects should have special documentation work clearly specified. However, an architect's first LEED specification may not adequately address the additional documentation work roofing contractors eventually may be requested to furnish.

Roofing contractors bidding or negotiating their first LEED projects should discuss with the projects' architects what unusual or special efforts will be required. Although any unusual or special efforts should be identified in the bidding documents, they may not be if the architect has limited experience with LEED.

The future

I anticipate LEED certification will be commonplace within a few years for major corporate buildings and many public buildings. Although roof systems are a small part of the integrated whole-building approach LEED takes, the roof system part of LEED is significant.

It is, therefore, incumbent on roofing professionals to be aware of LEED and position themselves to be important team players in the certification process by performing the tasks already mentioned in this article.

Thomas L. Smith is president of TLSmith Consulting Inc., Rockton, Ill.

Professional accreditation

The U.S. Green Building Council (USGBC) also has a Leadership in Energy and Environmental Design (LEED) Accredited Professionals™ Program. Candidates for accreditation must pass an exam that tests their understanding of sustainable practices and principles and familiarity with LEED requirements, resources and processes.

USGBC provides LEED-training workshops—visit USGBC's Web site, www.usgbc.org, for schedules and locations. Workshops also will be presented at USGBC's greenbuild International Conference and Expo held Nov. 12-14 in Pittsburgh.

An increasing number of building owners require a LEED Accredited Professional be a member of design teams.

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