A container is disclosed comprising a first sidewall having a first layer and a second layer. The second layer overlaps a portion of the first layer to define an overlap area. A sealing flange extends from the first layer outward of the overlap area. A second sidewall is connected to the first sidewall along the sealing flange to define an inner chamber therebetween. The second sidewall and the sealing flange define a first layered structure having a first number of layers along the sealing flange. The overlap area and the second sidewall define a second layered structure having a second number of layers. The second number of layers is greater than the first number of layers. The container is sealed by positioning peripheral edges of the first and second sidewalls into registration so that the overlap area is substantially centrally disposed over the second sidewall and applying sealing energy to the first number of layers to define a peripheral seam.