This is the gold beneath the streets, the lifeline for an obsolete industrial building.

It deployed people from an obsolete building in downtown Detroit to other space, saving $6 million a year.

"The bigger issue," Ms. Hackett said, "is how to deal with obsolete buildings in the city."

Artist created living spaces on the upper levels of obsolete industrial buildings, sometimes located in the heart of the city.

By 1908, the growing complexity of city government had made the building nearly obsolete as a government center.

New construction and the conversion of obsolete commercial buildings into residences has been a primary factor for growth in the central city.

However, in an effort to modernize the hospital, many of the unused and obsolete buildings were demolished in 1967.

The cost of constructing an obsolete building isn't considered relevant to market value.

He then demolishes obsolete buildings and puts up a commercial structure to be divided to suit the tenant.

For years, we've been calling for programs to convert some of the obsolete buildings from office to residential space.