One of Pittsburgh’s most beautiful buildings, the Union Trust Building, is rapidly moving along with a $40 million makeover. A year ago the building, formerly a Mellon Bank Center, was virtually empty, and most observers wondered if anyone would buy and lease it. Los Angeles based Mika Realty bought the building this winter for about $40/square foot, and announced plans to bring the structure up to LEED standards and renovate the base building. Now their investment looks like the steal of the decade.

With ink still drying on a 170,000 square foot long-term lease with Siemens Energy, construction is underway on the tenant buildout, plus renovations to toilet rooms, lobby, storefronts, common areas, and a new garage. Construction manager CB Richard Ellis, whose brokerage also handled the leasing, has contracted with Precision Builders for interiors, and Huckestein Mechanical, Preferred Fire Protection and Star Electric for the Siemens MEP work. The first of Siemens employees to relocate will begin occupying the fifth floor in early October.

Upgrading the building to LEED standards helped land Siemens as a lead tenant (no pun). According to CBRE’s Jeremy Kronman, Siemens worldwide corporate standards call for its facilities to be sustainable.

If you are familiar with the Flemish Gothic design of Frederick Osterling, done for Henry Frick in 1915, you probably remember that the central core of the building is open to a spectacular ceiling. Renovating a century-old building to keep up with contemporary needs and amenities for both office and retail tenants will be a challenge for architect Burt Hill.