High performance sliding doors with new glazing technologies offer many benefits. They do more than a better comfort of living, beauty and protection, they deliver energy and cost savings. Window replacement ct In heating season old windows and doors are a major source of heat loss, discomfort, and condensation problems. During winter months, high performance windows and sliding doors with lower U-Factors reduce heat loss, give better insulation value. They prove to have interior glass surface warmer, provide greater comfort and minimize condensation. Therefore, in cooling season, old drafty windows and sliding patio doors are a major source of heat gain. New windows and patio doors with Low-E glass reduce solar heat gain from the summer sun, helping to keep your home cooler. Window replacement ct The lower the solar heat gain coefficient ( SHGC ), the less solar heat it transmits.