Dobie, Balz and Watson houses were torn down this summer to make way for two new six-story dorms that will house more students, and be greener and more efficient.

The new residence halls are being constructed on the sites of Watson and Dobie; the site of Balz will become a recreation field and a one-story commons building. This is the latest step in a plan to replace 11 1960s-era residence houses with seven newer buildings and increase the number of rooms for first-year students by 10 percent.

Trish Romer, director of plans and programs with the Housing Division, says the dorms “have gone through their systems’ useable life” and that the cost of repairing and upgrading exceeds the replacement cost, estimated at $40 million. She adds that approximately 75 percent of the materials from the demolished dorms will be recycled.

Rendering of the new six-story dorms.