Low-E (low emissivity) glass has a microscopically thin, transparent coating that reflects long-wave infrared energy. This coating is not visible and allows as much natural light into the house as possible, but it does however help protect your home from unwanted UV rays. These UV rays can burn your skin, fade your carpets and damage your furniture, if they are constantly shining into your home. This transparent coating on windows also helps control infrared light as it enters and leaves a room in your home.
So does this glass help save energy? As a matter of fact it does. It helps keep your home warmer in the winter by reflecting some of the segments of the sun’s light spectrum into the home, and keeps your home cooler in the summer by reflecting some of the segments back outside. It acts as an insulator, helping cut energy costs and saving you money on heating and cooling bills.