Great Glazing: 400 Market St.
The basics: The 40-year-old, 12-story 400 Market St. office building in Philadelphia received an energy makeover with the conversion of its existing single-pane windows to triple-glazed insulating glass units. Windows on the 200,000-square-foot building were upgraded with the Renovate by Berkowitz window retrofitting system. The RbB system was installed in 50 working days at 400 Market St., two to three times quicker than estimates for a traditional rip-out-and-replace project, according to a J.E. Berkowitz release. The building was part of a U.S. Department of Energy project to demonstrate the ability of low-E retrofit glazing systems to significantly improve the energy efficiency of older commercial and residential buildings, according to the release. Using energy modeling software, J.E. Berkowitz estimated that the retrofit would reduce annual energy costs by $55,000. The first results since the project was completed show the building outperforming the projection, according to the release.
"While our study has just started, preliminary observations are very encouraging," said Thomas Culp, manager of the DOE project. "In November and early December, the east-facing offices showed about a 27 percent reduction in heating and cooling energy use, and the north-facing offices showed more than a 50 percent reduction."
The glass and systems: Renovate by Berkowitz Platinum system, which features one lite of PPG Solarban 60 and one lite of clear glass, separated by an argon-gas-filled cavity. A spacer system hermetically seals the insulating glass unit to the interior surface of the existing glass, creating a permanent, no maintenance attachment, according to the release.