Gwinnett commissioners approved Tuesday night the zoning changes necessary for Northside Hospital to build a large new medical facility near the Mall of Georgia.

Northside, which recently merged with Gwinnett Medical Center, plans to build two 100,000-square-foot buildings on the northwest corner of Ga. 20 and Rock Springs Road. Gwinnett officials approved a request to rezone the 20-acre property to a commercial use and granted permission for the buildings to be up to 67 feet tall.

Building heights are generally restricted to 45 feet.

The exact purpose for the new Northside facility is unclear. But attorney Sharon Gay said Tuesday that Northside likes to have auxiliary medical offices in communities where it operates hospitals.

Before the merger with Gwinnett Medical was finalized in August, Northside did not have a presence in Gwinnett. It now operates Northside Hospital Gwinnett (formerly Gwinnett Medical Center-Lawrenceville) and Northside Hospital Duluth (formerly Gwinnett Medical Center-Duluth),  as well as Northside Gwinnett Extended Care Center and Northside Gwinnett Joan Glancy (formerly the Glancy Rehabilitation Center in Duluth).

Gwinnett Medical Center’s smaller offices and clinics around the county are also now part of the Northside system.

The planned medical office buildings near Buford are not far from the Exchange at Gwinnett, a proposed mixed-use development where the Gwinnett commission approved a special tax district on Tuesday.