Attached Greenhouse – Custom built attached polycarbonate greenhouses, sunrooms and solariums are often a wise addition choice for the builder. The Sundance Supply approach is a Multiwall Lexan Polycarbonate sheet covering and the Base & Cap Installation System. The customer provided the frame, and remaining building components, for an elegant solution. Together this approach provides a watertight, attractive and long life attached structure, often costing significantly less than a prefab kit, that still requires customization.