Well Treated. Power Preserved glulam beams are treated with Cop-Guard, a solvent-based copper naphthenate formulation. According to the maker, they’re less likely than CCA- and ACQ-treated beams to warp, twist, cup, bow, swell, or shrink, so original design values can be used. They’re stainable and paintable and noncorrosive to fasteners and come in 3 1/2- or 5 1/4-inch widths, with depths from 9 1/4 to 18 inches and spans up to 52 feet. Prices start at $8.75 per foot. Anthony Forest Products, 800/221-2326, anthonyforest.com.