The Window Source of Mankato

627 S Front St. Mankato, MN 56001

Call us today!




The only accurate method to compare windows is to look at the NFRC rating for each one you are thinking about. NFRC labels that have received independent accreditation rate the general window performance using the U-Factor and Solar Heat Gain Coefficient (SHGC). The lower these ratings are, the better the window will perform. U-Factor or SHGC should be prioritized based on your climate. 

Regardless of the sales pitch, you should choose the NFRC ratings that are optimal for your environment and your financial situation.

Q: What is an ENERGY STAR® rated window?

You can choose windows that are energy-efficient and climate-adapted with the help of the federal government’s ENERGY STAR® window certification program. A window needs to perform at least to the minimums below to qualify. These requirements, which are based on the NFRC’s entire window performance ratings, vary depending on the climate zone:

  • Northern Zone (blue): U-Factor of .30 or less, SHGC any
  • North Central Zone (yellow): U-Factor of .32 or less, SHGC of .40 or less
  • South Central Zone (orange): U-Factor of .35 or less, SHGC of .30 or less
  • Southern Zone (red): U-Factor of .60 or less, SHGC of .27 or less

Q: Does The Window Store install ENERGY STAR® windows and patio doors?

Yes – Any window or patio door ordered with a Low E glass upgrade must meet the ENERGY STAR® standards for the climate zone. This promise is always offered in writing on your contract paperwork to ensure that you order and receive the best Low E glass that is suited to your particular temperature zone.

Q: Are there tax credits available when replacing windows and doors?

With our ENERGY STAR® products — yes! A 10% federal tax credit worth up to $200 for windows and $500 for patio doors that adhere to ENERGY STAR® standards may be available to you. These tax credits were set to expire in 2011, however a new law called “The American Taxpayer Relief Act of 2022” extended them into 2023 and retroactively to 2022.

Q: How can The Window Source be so much more affordable than their competitors?

The Window Source can provide you with high-quality vinyl windows at a very affordable price because of our wide national purchasing power. Our low pricing and straightforward purchase procedure also enable us to operate at a high level of efficiency and pass the savings on to you.

Q: Is the installation process as important as the window product itself?

A window needs to be accurately measured to suit the opening and leave space for plumbing and squaring the new window. No matter how high the quality of the new window, if it is not squared and correctly plumbed, it will not seal and function well.

Call The Window Source Today For A Free Estimate!