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As you consider replacing your windows or doors, look for these indicators that your old windows or doors need to be replaced:
Poor performance
Opening and closing is a difficult task; air leaks in, out or around the window; condensation or fogging occurs on or between glass panes.
Safety
Windows that dont open easily or are painted or nailed shut may prevent a safe escape during a fire when seconds count.
Looks
Chipping, deterioration and water stains on the window or the area around the window (inside or out).
Effort
Cleaning is a major hassle; replacement parts are hard to find or even non-existent.
Improve the energy efficiency of your home
Keep your home cooler in the summer and warmer in the winter by opting for Low-E (low-emissivity) glass coatings. Low-E helps reduce heat transfer and ultraviolet (UV) rays that can fade carpets, walls and furniture.
You also can reduce heating and cooling costs by replacing old single-pane windows with todays energy-efficient double- or triple-pane windows.
Select windows and doors that have earned the ENERGY STAR distinction to ensure you are maximizing potential savings to your heating and cooling costs.
Other Considerations
To keep the exterior appearance consistent, consider replacing all the windows on one side (or one level if its a two-story house) at the same time.
If youre replacing siding, replace windows before the siding, so that siding can be fit to the new windows, for a neater appearance and better overall energy efficiency.
If your window frames are in excellent condition, the easiest way to replace them is to remove old sashes and put a replacement window into the old frame. This allows the existing trim to remain in place. If frames are worn or damaged, replace the entire window unit.
article at HomeRenovationGuide.com