The name of the building refers to the "gatehouse" function it will serve to engage students in their academic endeavors and careers in the scientific community. The initials designate the anonymous donor of a $35-million gift that funded the new construction and a major addition and renovation to Galileo Hall (Phase II of the project), one of the original buildings built on campus 70 years ago.

Founded in 1863, St. Mary's College has been located on the Moraga campus since 1928. Eleven of the original buildings, designed by architect and engineer John Donovan, are still in use today. Donovan chose to evoke the Spanish Colonial Architecture popular in California at the time. The new Science Center is the first large project constructed on the north side of the campus, redefining the character and views along De LaSalle Drive.

J.C. Gatehouse Hall is a new three-story, 55,374-sf structure (Type B occupancy, Type II--one hour construction type and fully sprinklered). The structural system is steel "eccentric braced frame, EBF" lateral force resisting system with drilled pier foundation. The exterior enclosure is cement plaster (stucco), on metal studs, with a clay-tile mansard roof. Mechanical equipment will be primarily located within a roof well shielded by the mansards and in the mechanical yard adjacent to the building.

The new building evokes the graceful Spanish Colonial tradition. Red clay tile roofs and decorative open eaves, white washed walls and deep-set windows, doors and ornamental grilles were chosen to fit within the established architecture of the central buildings.