Monadnock Family Services plans to buy Antioch University’s building at 40 Avon St. in Keene, the two organizations announced Thursday.

“Consolidating our services in Keene to one location has been a part of our strategic plan for some time,” Monadnock CEO Phil Wyzik said in a statement.

Antioch would lease part of the building from the mental health services nonprofit for up to 48 months after the sale while it finalizes plans for a new campus in Keene.

The university’s student body has been growing in recent years so the school needs a bigger space, said Chancellor William R. Groves.

“After almost 30 years at our Avon Street location, we are excited to be planning the development of a new, state-of-the-art campus in Keene to better meet the needs of our growing learning community,” he said in a release.

Antioch acquired the former Sprague & Carleton Furniture factory in 1993 and spent more than $5 million to renovate and expand the building, according to the school.

The national university, founded in 1852, also operates campuses in Los Angeles; Santa Barbara, Calif.; Yellow Springs, Ohio; and Seattle, as well as online.