Vinyl replacement windows can be the difference between a lower heating and cooling bills next season or a higher heating and cooling bill. Window openings in the exterior of a residential house services a number of very important functions, for example, ventilating, inviting light indoor, adding curb appeal, secondary means of egress. Once you have an energy assessment conducted prior to and after installing new energy star vinyl replacement windows, rebates and grans are just an application away(specifically in Ontario, Canada).