Finishing Mantels Builder’s Fireplace has noncombustible mantel options in several styles. They are made of either cement, metal, or cast stone. Walls The wall surrounding your fireplace plays an important part in the design and feel of your space. We have several noncombustible finishing material options that may fit your design needs. Doors & Screens Doors and screens are available for prefabricated units and custom masonry fireplaces. They can be customized to fit any style by choosing from many options of different glass colors, finishes, styles, handles, and more.