I just finished an order for a two layer 11"x15" sheet cake and after decorating it, it is now 15" wide and 20" long. My husband used a cement board for me and we covered it to make it look pretty - the flimsy cake board wouldn't hold the weight of this cake. The customer will transport it - but I would have preferred that the cake be enclosed. Does anyone have any suggestions or a source for heavy duty cake boxes? I've searched the Internet and find lots of things in the UK but nothing to speak of here in the US. Thanks very much for your suggestions.