The backboard is placed behind the artwork to provide a support and hold the art in the frame. We generally provide foamboard backboards as they are acid free and made specifically for framing. For larger frames (over one metre) or some specialist frames we use 3mm MDF as it is rigid and strong. It always adds a lot of extra weight and is only used when necessary for the best result. Many framers only use MDF largely because it is cheaper than foamboard, just as glass is cheaper than acrylic. We are committed to only using the best components, and do not compromise by using cheaper inputs.