Although the developer, Alter Group, declines to put a number on the cost, a reasonable estimate would begin at $100 million. Achieving Leadership in Energy and Environmental Design status, superior infrastructure and other design elements will increase the cost compared to other class-A buildings, Alter Group senior vice president Matthew A. Ward says the incremental costs are "less than you think." They also are likely to be recouped by tenants who see greater worker productivity in an environmentally friendly building with flexible floor plates and energy efficiency. "The costs might be 5% to 10% more, but the returns on the investment are 10-fold in terms of worker productivity, quality of life and economic sustainability," Ward tells GlobeSt.com.

Ward's task now is finding at least one tenant willing to take at least 50,000 sf to anchor the building, but he has identified "two or three genuine prospect." Although the East-West Corridor remains soft, as total vacancy in the largest suburban submarket starts the year at 25.4%, according to US Equities Realty, Inc., the highest in the entire market. However, the 93% of the 517,500 sf in Corridors I, II and III is leased, with 148,000 sf in deals signed last year, according to president Michael J. Alter.

"We feel pretty confident," Ward adds. "Not only are the buildings' locations attractive, but their infrastructures are superior."