You can get a new window anywhere; but Stanek windows deliver benefits far beyond style. Our energy-efficient windows and patio doors are engineered to outperform the elements and the competition. To reinforce our commitment to quality, we independently certify and test our windows and patio doors. We offer advanced thermal protection that increases energy efficiency and lowers energy bills. With Stanek Windows, you will have peace of mind knowing you have made a beautiful choice with lifetime performance. Stanek® brand vinyl windows and patio doors are made exclusively by Great Day Improvements, LLC, a manufacturer and installer of windows, doors and Patio Enclosures® brand sunrooms. We custom design and custom manufacture all our products specifically for you and your home. Our state-of-the-art manufacturing facility and company headquarters are located just south of Cleveland, Ohio.