AKF Group, a consulting engineering firm, is moving its Boston offices closer to South Station from the Seaport District as the firm expands and rents in the red hot South Boston neighborhood continue to soar.

AKF will relocate to a second-floor space at 99 Bedford St. and double its office space to 15,000 square feet. By relocating, the company will shave about $8 per square-foot off its current Seaport rent, according to Barry Dube, a principal at Cresa Boston, which was involved in the deal.

AKF offices are currently at 41 Farnsworth St., but the Seaport space, across the street from the John Joseph Moakley U.S. Courthouse, isn’t enough room for the growing firm.

Rick Lowe and Brandon Leitner of Cresa Boston represented AKF in the transaction.