Acrylic Block Windows provide an excellent privacy and decorative solution for any area of the home. Highly energy-efficient, lightweight and easy to install, acrylic block is a great alternative to real glass block windows. Acrylic block will not yellow or change in appearance over time. Acrylic block windows can be purchased in virtually any size, height and width and are available in casements, awnings and hoppers as well as the traditional fixed picture windows. Special shapes and sizes are also available including round or arch top windows. Acrylic block provides better thermal performance than glass block. Energy Star-rated versions are available for most zones.