Our 5-1/2" crown moldings is good for high and vaulted ceilings. It is often used in commercial applications also. To do this in wood would require a built up crown using several pieces of crown. Easy to install - just paint, caulk and press.
5.5 Inch Vaulted Crown Molding
EPS Architectural Shapes
EPS architectural moldings and trim are lightweight and easy to install and finish