Renewal by Andersen is the replacement window division of the Andersen Corporation. With over 110 years of manufacturing windows and patio doors, Andersen knows a thing or two about homes. First, creating a whole separate window division of their company to handle replacing existing windows in southern Maine homes is our specialty. We are Certified Master Installers of double hung, casement, gliding, awning, bay and bow, patio doors and specialty shapes such as pentagon, half-round, quarter-round even springline..