A flexible edge seal for a vacuum insulating glazing unit. The flexible edge seal comprises an elongate first edge seal portion having a substantially constant first cross-section and including a bonding flange at one end, a weld surface at the other end and a first center portion therebetween. An elongate second edge seal portion has a substantially constant second cross-section and includes a bonding flange at one end, a weld surface at the other end and a second center portion therebetween. Each bonding flange includes a substantially flat portion adapted for hermetic bonding to a surface of a different one of a pair of glass panes. The weld surfaces are hermetically joined to one another forming a hermetic seal therebetween. At least one of the first center portion and the second center portion has a convolute cross-section and is asymmetrical to the other center portion.