The LEED Approach to Analyzing Green Buildings

The LEED system originated with the U.S. Green Building Council (USGBC). This is a nonprofit group with voluntary membership. LEED was created as a way to define high performance green buildings, set quantifiable targets and goals, recognize leaders, promote improvement over time, stimulate green competition, and raise consumer awareness.

LEED looks at how a building performs in the following categories: sustainable sites, water efficiency, energy and atmosphere, materials and resources, indoor environmental quality, innovation and design process, and use of a LEED-accredited designer. Thus, it is a design based approach to analyzing the building, and not based on actual usage data. Based on the LEED point system, a building can earn a certified rating (the lowest rating), or the higher ratings of silver, gold, or platinum. When a building is LEED-certified, it receives attention on the USGBC website and other publicity opportunities, and perhaps tax credits and other financial perks.

EnergyStar

Unlike LEED, which is run by a nonprofit, Energy Star is a government program run by the EPA (Environmental Protection Agency) and the DOE (Department of Energy). The Energy Star tools are free for anyone to use at www.energystar.gov. The website helps consumers find products that have earned the Energy Star label for being efficient and conserving energy. You can assess your own home on the site and find an Energy Star contractor for home improvements.

The site’s Portfolio Manager allows you to enter a building’s data, and compares the energy use to a database of similar buildings. If you have all your utility bills handy, the process should take about half an hour to complete online. Typically an ENERGY STAR certified home is 15%-20% more energy efficient than an average minimum-code home.

The site promotes Energy Star qualified new homes and builders, and also has a commercial building section. To earn the Energy Star label on commercial building or be recommended as a service provider, the building must be energy efficient and the contractor must use environmentally responsible materials and techniques in the building or remodeling.

Participation in an Energy Star audit is voluntary, as it is with LEED. While USGBC sets the rules for LEED, with Energy Star the ratings are based on best practices of other Energy Star partners. As with LEED, the Energy Star label can be a marketing tool for building owners.

Home Energy Rating System

HERS was designed in 2006 by the Residential Energy Services Network (RESNET). A HERS rater enters a home’s data into a computer program and the data is compared to a fictional reference home in the system. According to the Green Resource Council, “an index is assigned to each modeled home as an indicator of its energy efficiency. A score of 100 is equivalent to minimum IECC recommendations; a score of 0 equals zero net energy use. A score of 85 or lower meets Energy Star requirements.” 

The RESNET website has an interactive guide to gauging your home’s energy usage and also has sections on how to make your home more energy efficient. RESNET also qualifies contractors and builders who meet their requirements. Builders across the country are embracing the HERS index as their preferred rating scale when evaluating their homes. It was widely publicized in national newspapers that a new home in Gilbert Arizona in May of 2012 became the one-millionth home rated by the HERS Index.

The HERS index is simple and straightforward, compared to LEED and Energy Star. This is the method I would prefer to use if I was marketing a home’s energy efficiency. HERS has been compared to a vehicle’s miles-per-gallon sticker, and it’s just as easy to compare houses with a HERS index stick as you would look at a car sticker before purchasing a vehicle. 

According to the Energy Star website, “EPA believes that energy efficiency is the first step to green building, and that all green buildings should be energy efficient. Using ENERGY STAR tools and resources, and earning ENERGY STAR recognition, will ensure that green buildings (whether certified by LEED or another system) are truly energy efficient.”  The two are not competing systems, but work in conjunction with one another. HERS fits into this analysis in a similar way. A building that is Energy Star labeled should be well on its way to being LEED certified, should the owner wish to pursue that avenue as well. As builders around the country start to market their projects with HERS Index ratings, consumers will be better able to make informed decisions reading their new home’s energy usage.