Installing a new door can make a big difference to the interior or the exterior of a home. If you think that painting your existing door will not improve the door enough for you, then a new door is a wise investment. Many people also replace their doors when they are drafty, badly insulated, or do not fit properly into the door frame. A high quality new door can lower the costs of heating or cooling your home because it probably has better insulation than your old door. Vintage doors are often made of cheap materials like plywood, while today's doors are better made, although you may end up paying more dearly for them. For instance you can pay five hundred dollars for a new front door, but the door is usually reinforced with metal for safety reasons.