Can you make cornice shapes out of foam? Yes, and there are many different styles we can help you with. Cornices are beautiful additions to any house or structure. There are many different options of foam exterior cornices, exterior door cornice moldings, sills, trims, columns. They add a rich and distinctive style. Often we neglect the decorative options that we can add to the outside of our homes. Foam is weather resistant, light-weight and easy to install. It can also be easily painted to match your current color scheme. Take a look and you will be surprised by the many different details that can be carved into the surface of the eps foam with provide.