All Projects and Incentives

Replace Your Windows

About this Project

The Final Step in Energy Efficiency Improvements

Many people believe that energy efficiency starts with replacing windows. And while windows are very important (and an energy audit may recommend replacement), a wiser strategy is to take care of all the smaller projects first. Caulk any leaks, weatherstrip around windows and doors, install a programmable thermostat, etc. (We have all of those projects on My Green Montgomery) Replacing a HVAC or adding insulation are often better bangs for your buck than windows, and they reap savings faster.

Now that you've taken care of everything else, decide if making the investment in new windows is right for your home.

When you are upgrading windows and potentially replacing frames, consider upgrading your window shading to be more insulative or reflective, especially on the southern side of your home. By reflecting off some of the sun in the summer afternoon, you can reduce how much cooling is required.



Since replacing your windows should be the last action on your energy to-do list, first evaluate what other projects you should do first. Tackle the low cost, high impact projects first!  If you are looking for a place to start, we recommend getting a Quick Home Energy Check or a Home Energy Assessment.


Replacing Windows

The Department of Energy, through its Energy Saver Do-It-Yourself (DIY) Projects offer easy, instructions to install exterior storm windows with low e-coating. It even has a shopping list!

Follow the ENERGY STAR window buying guide.

If you choose an ENERGY STAR-qualified window, frame material is already factored into the rating. But as a general rule of thumb, look for the lower U-factor, which describes the rate of heat flow through the window. Vinyl, wood, fiberglass, and some composites have lower U-factors than metal. Check the U.S. Department of Energy's webpage for more information.

If you have questions on the different types of glass and coatings, it may be best to seek the advice of a window professional. You’ll need to look at which side of the house the window faces and other factors. But here are a few key points to keep in mind:

  • Windows with low-e coating can cost up to 15-30% more but can help reduce heat gain and save between 30-50% in energy cost.
  • Windows can have either soft or hard low-e coatings. Soft coatings may peel over time, while hard coatings are more resilient.
  • Windows may be filled with argon or krypton gases. These inert gases decrease the U-factor (lower U-factors are more energy-efficient), and therefore the rate at which heat moves through the window. Krypton is more expensive but more effective at slowing heat transfer.


Image of homeowners installing energy efficient windows.


If you scheduled a Home Energy Assessment, the contractor may provide rebates to help with the cost of installing energy efficiency windows. It depends on what the contractor recommends for your home.

Additional assistance include:


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