Sliding patio door systems are becoming more and more ubiquitous across America, for practical reasons. They save floor space, which is great for maximizing your finished real estate. Thanks to design enhancements, many products now bear the ENERGY STAR seal for minimal air leakage. Gliding units cover larger openings too, making plentiful ventilation possible, and capturing wider views. Most importantly, they have fewer moving parts, rendering them less prone to mechanical problems.