The present disclosure relates generally to siding, for example, suitable for covering a wall surface. The present disclosure relates more particularly to a frame for a wall panel. The frame includes a support strip extending in a lateral direction across the width of the wall panel and has first and second ends. The frame also includes a row of columns extending in a first direction from the support strip. Each column includes a proximal end attached to the support strip and a free distal end. The row of columns includes a first column disposed at a first end of the row of columns and laterally offset from the first end of the support strip, and a second column disposed at a second end of the row of columns and laterally offset from the second end of the support strip.