I have 16 ft long by 14" wide long beams in my kitchen and dining room. They are of construction grade wood, and, therefore, not worth refinishing. I would like to clad them. How can I accomplish that without the boards warping? Additionally, where can I get material that long? Is there a way to disguise the joints if long boards are not available? If all else fails, is there an paint product that can be used indoors to give them a weathered look?