This is the most compelling reason to change a door or window,. On top of testing your patience, windows and doors that stick aren't giving you the optimum benefit in terms of convenience and efficiency. Performance is also tied to safety -- if doors our windows are not opening properly they can be a safety hazard.

Check for drafts around doors and windows by moving a lit candle slowly around the edges. If the flame flickers, you have a draft -- one of the biggest drains on the energy efficiency of your home. Drafts add up to real dollars on your heating and cooling bills, so this is, for many people, the impetus to replace their windows or doors.

Older windows and doors require maintenance -- scraping, painting and caulking. Newer windows and doors feature low maintenance cladding, a protective exterior covering that requires minimal maintenance. Many newer windows also make cleaning easy with a convenient tilt feature that allows you to wash them from inside your house.

Curb appeal is vital if you're selling your house and a satisfying lifestyle enhancement if you plan to stay in your home for years to come. Updated windows and doors not only improve energy efficiency and lower maintenance costs, they make your house look more appealing as well.