As a rule, the older your windows and doors are, the more you have to spend on electricity. This is not because modern windows and doors are of higher quality and with better thermal resistance, but because of the natural shifting of your house and the simple aging of materials. First, in course of time old windows start to leak and let drafts inside the room. Secondly, old windows and glass doors start to let UV rays into the hous, causing your furniture and floors to fade.
New energy-sufficient doors and windows would allow to reduce up to 25% of your energy costs. Modern Glass doors and windows bring more natural light into your home and save you from having to turn on the house lights from morning to night. Most of modern doors feature double glazing and low-e coating, allowing warm air in during the winter and cool air in during the winter. Not only will you be comfortable in your home all year round, but you will also be spared from high electricity bills.