conducted through LEED Online, USGBC's web-based service. The GBCI also utilizes LEED Online to conduct their reviews. LEED energy modeling Applicants have the option of achieving credit points by building energy models. One model represents the building as designed, and a second model represents a baseline building in the same location, with the same geometry and occupancy. Depending on location (climate) and building size, the standard provides requirements for heating, ventilation and air-conditioning (HVAC) system type, and wall and window definitions. This allows for a comparison with emphasis on factors that heavily influence energy consumption. The number of points achieved in this credit is proportional to the predicted energy savings. This method has been criticized for inaccurately predicting actual energy usage. The USGBC admits that "current information indicates that most buildings do not perform as well as design metrics indicate. As a result, building owners might not obtain the benefits promised." LEED for Homes rating system The process of the LEED for Homes rating system, available in the U.S., Canada and Sweden, differs significantly from the LEED NC rating system. LEED for Homes projects are low-rise residential and are required to work with either an American or a Canadian provider organization and a green rater. The provider organization helps the project through the process while overseeing the green raters, individuals who conduct two mandatory site inspections: the thermal bypass inspection and the final inspection. Although LEED for Homes is typically viewed by the construction industry as a simpler rating system than LEED NC, the latter does not require an on-site inspection. The provider and rater assist in the certification process but do not themselves certify the project. Performance Research papers provide most of what is known about the performance and effectiveness of LEED in two credit category areas: energy and indoor environment quality (IEQ). In one study of 953 New York City office buildings, 21 LEED certified buildings collectively showed no energy savings compared with non-LEED buildings, although LEED Gold buildings "outperformed other NYC office buildings by 20%". IEQ-related studies provide two contrasting results: the first used occupant survey results in 65 LEED buildings and 79 non-LEED buildings and concluded that occupants of both groups had equal satisfaction with the building overall and with the workspace. The second IEQ study used occupant interviews and physical site measurements at 12 LEED buildings to report superior indoor environment performance compared with 12