27 Best Window Replacement Companies in Flagg, IL (2023 Reviews)
Window Companies Near Me
Are you thinking of upgrading your windows? Our guide to the best window installation companies can help you narrow down which one to choose.
We analyzed all the top window installers in Flagg and selected the top 27 based on:
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Customer reviews
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Window replacement expertise
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Popularity with home-owners like you
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Updated May 04, 2023
Why you can trust EcoWatch
Whether you're updating for aesthetics or have damaged windows, windows play a crucial role in conserving energy in your home. If your house has outdated, drafty windows, your AC or heater could be working overtime to heat or cool your house. This means higher power bills.
Installing upgraded, efficient windows on your house can help you save money every month on your electricity bills — and you can help the environment as well.
Efficient windows are of particular importance in Flagg, where the temperature varies throughout the year. According to Energy Star, making the switch to energy-efficient windows can save the average homeowner up to $309 a year.
Best Overall
Renewal by Andersen
- Manufactures products in-house
- Great industry reputation
- Award-winning company
- No lifetime warranty
Best Affordability
Window World
- Lifetime warranty
- EnergyStar Partner
- Great industry reputation
- Quality of service will depend on your area
Best Warranty
Universal Windows Direct
- Lifetime warranty
- Makes charitable contributions
- Wide variety of products and services
- Quality of service will depend on your area
Best Window Replacement Companies in Flagg
The EcoWatch Reviews team evaluated dozens of installers in Flagg to find the top window companies for our readers. The companies we've included in this article scored best in our categories: energy-efficient offerings, customer service, price, availability and more.

Renewal by Andersen
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Manufactures products in-house
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Great industry reputation
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Award-winning company
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No lifetime warranty
Renewal by Andersen has the best availability in Flagg. This provider has 27 years of experience in the window installation business, and it has proved to be one of the most reputable companies in Flagg.
If you're looking for a company that uses in-home estimates and advanced digital tools to help you plan and visualize your project before getting started, this may be the provider for you.
Energy Efficiency of Renewal by Andersen WindowsRenewal by Andersen carries some Energy Star windows, but note that not all its windows are energy-efficient, so be sure to mention that you want Energy Star windows when inquiring. A handful of windows manufactured by the Andersen corporation were awarded Energy Star’s “Most Efficient” in 2021, and Andersen was named Energy Star’s Partner of the Year in 2019.
How much does Renewal by Andersen cost in Flagg?Andersen does not detail prices on its website, but based on customer feedback, you can expect to pay anywhere between $750 to $1,250 per window for an installation with Andersen. Getting a free quote on its website is the best way to get more accurate pricing information.

Window World
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Lifetime warranty
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EnergyStar Partner
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Great industry reputation
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Quality of service will depend on your area
Window World provides windows expertise in Flagg. It's the largest window replacement company in the country, known for its vinyl windows and affordability. This window installation company has been operating since 1995 and currently serves 200 locations nationwide. The provider has plenty of positive reviews from customers on online review websites.
It has established itself as a company that is certified by the Environmental Protection Agency (EPA) and Energy Star and supports charities like St. Jude Children’s Research Hospital.
Energy Efficiency of Window World WindowsWindow World has some Energy Star windows, but note that not all its windows are energy-efficient, so make sure you mention that you want Energy Star windows when inquiring. Its high-performance Low-E (low-emissivity) coatings and argon gas insulation offer exceptional efficiency and performance for any home.
How much does Window World cost in Flagg?Prices aren't listed on Window World's website, but it's known for offering some of the most affordable window installations around. You can request a free quote on its website for more information about pricing.

Universal Windows Direct
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Lifetime warranty
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Makes charitable contributions
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Wide variety of products and services
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Quality of service will depend on your area
Universal Windows Direct provides the best warranty in Flagg. It's a company that has grown immensely since its inception in 2002, and now has several franchise dealers nationwide. Universal has been in the window industry for about 20 years. Hundreds of positive reviews on customer review websites back the company's reputation.
You may want to consider going with Universal if you're looking for a company that has an industry-leading warranty covering products, parts and workmanship for life.
Energy Efficiency of Universal Windows Direct WindowsUniversal Windows Direct has some Energy Star windows, but note that not all its windows are energy-efficient, so make sure you ask for Energy Star windows when inquiring. The company offers energy-efficient UniShield brand windows. According to its website, UniShield window packages have higher gas fill rates and longer gas retention than most other brands on the market, and they are Energy Star products.
How much does Universal Windows Direct cost in Flagg?Prices aren't available on Universal's website, but installations typically range from $225 to $425 per window based on customer feedback. That makes Universal Windows Direct more of a budget-friendly option for window repair and replacements. Receiving a free quote on its website is the best way to get more accurate pricing information.

Window Nation
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Award-winning company
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Manufactures products in-house
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Custom designs
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Wide variety of products and services
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Installation not covered by warranty
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Limited service area
Window Nation has the best residential windows in Flagg. It's a company that serves hundreds of thousands of homeowners, mostly in the mid-Atlantic region of the U.S. Window Nation has been in the window industry for around 16 years. Hundreds of positive reviews on customer review websites back the provider's reputation.
It gives customers the opportunity to view products and to speak to a representative in person in its showrooms.
Energy Efficiency of Window Nation WindowsEach product has windowpanes coated with a Low-E (low emissivity) glaze that prevents damaging UV rays from heating your home. Plus, the spaces between double- and triple-pane windows are filled with argon gas that’s been proven to improve home insulation. Not all of Window Nation's offerings are Energy Star certified, so be sure to mention that you're interested in Energy Star windows when inquiring.
How much does Window Nation cost in Flagg?Window Nation doesn't have any pricing information displayed on its website, but based on customer feedback, you can expect to pay between $300 and $525 per window installed, making it a more affordable option compared to competitors. If you'd like to know for sure, you can ask for a quote on the company's website.
We've recommended providers with shining reputations, but bear in mind that these are national companies, so your service may differ depending on your local crew. We have tried to stay unbiased and transparent by describing pros and cons for every company reviewed.
More Window Replacement Companies in Flagg
Window World of Rockford
Loves Park, IL-
Good Customer Service
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Free assessment
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Educational Website
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Price Transparency
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Timely Service
Services Offered
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Energy-Efficient Options
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Glass Showers
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Bay Windows
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Sliding Glass
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Custom Window Designs
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Residential Windows
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Fast Delivery
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Commercial Windows
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Double-Hung
Windows, Doors and Siding by Opal Enterprises Naperville
Naperville, IL-
Good Customer Service
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Award-Winning
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Free assessment
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Educational Website
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Price Transparency
Services Offered
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Energy-Efficient Options
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Sliding Glass
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Custom Window Designs
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Stained Glass
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Residential Windows
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Fast Delivery
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Double-Hung
Schmidt Exteriors, Inc.
Aurora, IL-
Good Customer Service
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Award-Winning
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Free assessment
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Educational Website
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Price Transparency
Services Offered
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Energy-Efficient Options
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Bay Windows
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Custom Window Designs
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Stained Glass
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Residential Windows
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Commercial Windows
Mr. Handyman of Naperville
Geneva, IL-
Good Customer Service
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Award-Winning
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Free assessment
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Educational Website
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Price Transparency
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Timely Service
Services Offered
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Glass Showers
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Custom Window Designs
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Residential Windows
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Commercial Windows
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Double-Hung
XL Contracting
Roscoe, IL-
Good Customer Service
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Award-Winning
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Free assessment
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Educational Website
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Price Transparency
Services Offered
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Energy-Efficient Options
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Custom Window Designs
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Residential Windows
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Fast Delivery
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Commercial Windows
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Double-Hung
Casco Industries
South Elgin, IL-
Good Customer Service
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Price Transparency
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Free assessment
Services Offered
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Glass Showers
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Sliding Glass
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Custom Window Designs
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Residential Windows
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Aluminum Window Frames
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Fast Delivery
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Commercial Windows
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Double-Hung
Window Concepts
South Barrington, IL-
Good Customer Service
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Educational Website
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Price Transparency
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Free assessment
Services Offered
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Energy-Efficient Options
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Bay Windows
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Sliding Glass
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Custom Window Designs
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Residential Windows
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Commercial Windows
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Double-Hung
Meklee Interiors
St. Charles, IL-
Good Customer Service
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Price Transparency
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Free assessment
Services Offered
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Energy-Efficient Options
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Glass Showers
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Bay Windows
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Sliding Glass
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Custom Window Designs
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Residential Windows
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Commercial Windows
WarmDreams Windows & Doors
East Dundee, IL-
Good Customer Service
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Price Transparency
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Free assessment
Services Offered
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Energy-Efficient Options
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Bay Windows
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Sliding Glass
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Custom Window Designs
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Residential Windows
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Fast Delivery
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Double-Hung
A & G Glass & Mirror Inc
West Chicago, IL-
Good Customer Service
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Free assessment
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Educational Website
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Price Transparency
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Timely Service
Services Offered
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Glass Showers
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Sliding Glass
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Custom Window Designs
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Residential Windows
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Commercial Windows
Pella Windows & Doors of Rockford
Rockford, IL-
Good Customer Service
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Educational Website
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Price Transparency
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Free assessment
Services Offered
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Bay Windows
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Sliding Glass
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Custom Window Designs
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Residential Windows
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Fast Delivery
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Double-Hung
Naperville Windows and Doors
Naperville, IL-
Good Customer Service
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Educational Website
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Price Transparency
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Free assessment
Services Offered
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Sliding Glass
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Custom Window Designs
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Full-Service Installations
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Residential Windows
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Fast Delivery
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Commercial Windows
Home Services at The Home Depot
Peru, IL-
Good Customer Service
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Educational Website
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Price Transparency
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Free assessment
Services Offered
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Glass Showers
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Bay Windows
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Custom Window Designs
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Stained Glass
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Residential Windows
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Aluminum Window Frames
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Fast Delivery
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Commercial Windows
Koolmaster Co. Inc.
La Salle, IL-
Good Customer Service
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Educational Website
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Price Transparency
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Free assessment
Services Offered
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Glass Showers
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Sliding Glass
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Custom Window Designs
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Full-Service Installations
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Residential Windows
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Commercial Windows
All Storm Solutions, Inc.
Naperville, IL-
Good Customer Service
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Price Transparency
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Award-Winning
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Educational Website
Services Offered
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Sliding Glass
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Custom Window Designs
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Full-Service Installations
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Residential Windows
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Aluminum Window Frames
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Commercial Windows
Home Services at The Home Depot
Algonquin, IL-
Good Customer Service
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Educational Website
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Price Transparency
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Free assessment
Services Offered
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Glass Showers
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Bay Windows
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Custom Window Designs
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Stained Glass
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Residential Windows
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Fast Delivery
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Commercial Windows
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Double-Hung
Advanced Window Systems
Rockford, IL-
Good Customer Service
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Award-Winning
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Free assessment
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Educational Website
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Price Transparency
Services Offered
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Energy-Efficient Options
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Bay Windows
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Sliding Glass
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Custom Window Designs
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Residential Windows
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Commercial Windows
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Double-Hung
Sunset Siding Windows & Roofing
St. Charles, IL-
Good Customer Service
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Price Transparency
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Timely Service
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Free assessment
Services Offered
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Custom Window Designs
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Full-Service Installations
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Stained Glass
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Residential Windows
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Aluminum Window Frames
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Fast Delivery
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Commercial Windows
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Double-Hung
Window Liquidators.com
Aurora, IL-
Good Customer Service
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Educational Website
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Price Transparency
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Free assessment
Services Offered
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Energy-Efficient Options
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Custom Window Designs
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Residential Windows
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Aluminum Window Frames
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Fast Delivery
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Tempered Glass
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Double-Hung
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Commercial Windows
Geneva Glass Works
Geneva, IL-
Good Customer Service
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Educational Website
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Price Transparency
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Free assessment
Services Offered
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Energy-Efficient Options
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Glass Showers
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Custom Window Designs
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Residential Windows
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Aluminum Window Frames
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Fast Delivery
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Commercial Windows
Window Well Services LLC
Elgin, IL-
Good Customer Service
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Free assessment
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Educational Website
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Price Transparency
Services Offered
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Aluminum Window Frames
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Residential Windows
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Custom Window Designs
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Fast Delivery
Great Outlook Glass
Dundee, IL-
Good Customer Service
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Educational Website
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Price Transparency
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Free assessment
Services Offered
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Glass Showers
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Sliding Glass
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Custom Window Designs
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Residential Windows
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Commercial Windows
Buffalo Roofing & Exteriors LLC
Oswego, IL-
Good Customer Service
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Award-Winning
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Free assessment
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Educational Website
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Price Transparency
Services Offered
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Commercial Windows
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Residential Windows
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Custom Window Designs
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Fast Delivery
Your Window Solutions
Lake in the Hills, IL-
Good Customer Service
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Educational Website
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Price Transparency
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Free assessment
Services Offered
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Energy-Efficient Options
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Sliding Glass
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Custom Window Designs
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Residential Windows
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Double-Hung
D-S Exteriors Inc.
Warrenville, IL-
Good Customer Service
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Educational Website
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Price Transparency
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Free assessment
Services Offered
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Glass Showers
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Sliding Glass
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Custom Window Designs
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Residential Windows
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Aluminum Window Frames
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Commercial Windows
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Double-Hung
Country Glass, Inc.
Beloit, WI-
Good Customer Service
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Price Transparency
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Timely Service
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Educational Website
Services Offered
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Bay Windows
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Sliding Glass
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Custom Window Designs
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Residential Windows
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Fast Delivery
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Commercial Windows
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Double-Hung
City Glass Company, Inc.
Janesville, WI-
Good Customer Service
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Educational Website
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Price Transparency
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Free assessment
Services Offered
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Glass Showers
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Custom Window Designs
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Residential Windows
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Aluminum Window Frames
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Commercial Windows
How Installing Energy-Efficient Windows in Flagg Saves You Money
By upgrading to energy-efficient windows, you and your family can benefit in several ways, including:
- Protect your investment: Upgrading your windows is an important part of maintaining your property and its value, especially if you have an older home.
- Decrease your carbon footprint: By using less energy once switching to energy-efficient windows, you'll also be lowering your indirect greenhouse gas emissions by about 12%, according to Energy Star.
- Save money on electricity bills: Because energy-efficient windows lower the amount of energy used to heat or cool your home, the switch can help you save about $309 annually on your energy bills in Flagg.
- Protect your valuables: Many energy-efficient windows have low-emissivity coatings, which not only insulate your home better, but also filter out damaging UV rays, preventing fading of your furniture, carpet and other valuables.
Estimated Cost of Window Replacement in Flagg
When researching window installation, each company provides different services and costs. Let's go over some average costs and services.
How Much Do New Windows Cost?
The typical cost to install a single window is about $600 but can range from $200 to $1,200. This is due to the fact that the cost of window installations depend on several factors specific to your home, such as the size, material and number of windows you need to install, as well as the location of your property.
It's important to bear in mind that windows with the best efficiency may cost more initially but can save you hundreds of dollars by decreasing your energy bills. Investing in certified energy-efficient windows can save Flagg homeowners $309+ a year when replacing single-pane windows.
Something else that influences the overall cost is the material of the frame you select. Aluminum frames are typically the least pricey and are sturdy and relatively maintenance-free, but they offer poor insulation. On the other hand, wood frames cost the most because they are aesthetically pleasing and offer decent insulation. Fiberglass and vinyl frames provide good insulation as well and cost somewhere between the other two.
What Services do Window Installers Offer?
The first question to ask yourself when planning to replace your windows is: Should you get a full-frame installation or a pocket installation?
Full-frame installations are necessary when you want to change the style of your windows or your window has significant deterioration. With this service, your professionals will replace the total window, including the sill, trim and frame. A pocket installation involves installing a new window within the frame that's already there. So, instead of removing the whole window and rebuilding it, the installer will just slide the replacement window (also called a retrofit or insert window) into the frame.
If you're unsure which type of window installation service you need, your installer should be able to assist you. Generally, the choice depends on factors such as the age and condition of the home, the type of building material, budget and time restrictions.
Best Overall
Renewal by Andersen
- Manufactures products in-house
- Great industry reputation
- Award-winning company
- No lifetime warranty
Best Affordability
Window World
- Lifetime warranty
- EnergyStar Partner
- Great industry reputation
- Quality of service will depend on your area
Best Warranty
Universal Windows Direct
- Lifetime warranty
- Makes charitable contributions
- Wide variety of products and services
- Quality of service will depend on your area
How We Choose the Best Window Installers in Flagg
The EcoWatch Reviews team is different from other reviewers, as we're examining these companies through a sustainability lens. We've reviewed the best window installation companies in Flagg mainly based on their energy efficient offerings, as it's the most sustainable option and the best one for homeowners. Energy-efficient windows have been shown to cut your energy bills by hundreds of dollars. Along with energy efficiency, our rating methodology takes the following factors into consideration:
Service Area
This one is self-explanatory, but we've chosen to highlight window installers that serve the Flagg area so you can find the best window installation company near you.
Work Quality
We're certain that you're not looking for a company to do a shoddy job installing windows. We've vetted each installer on this list to make sure its technicians are well-qualified and that the company has received lots of positive customer feedback to vouch for its service.
Customer Reviews
We analyzed patterns in recent online reviews to find the companies with the highest rates of customer satisfaction. Customer satisfaction might be the most important factor, as it indicates the quality of services across nearly every category, including warranty, cost, quality of installation, quality of parts, professionalism and more.
Cost
Cheaper windows certainly don't mean better windows, but we know many of our readers try to keep costs as low as possible. When analyzing the prices of providers, we awarded higher scores to companies with reasonable prices and accessible financing rather than "cheaper" services.
Warranty
Protecting your investment in new windows is important to many homeowners. That's why window installation companies that have lengthy warranties for products, parts and labor rank higher with EcoWatch.
Years of Experience
Because of Flagg's climate, homeowners need to be wary of water damage, low efficiency and rot. We factored in local experience to reflect the ability of Flagg window companies to prepare homes for the climate. If a company has less than 10 years of experience, it loses points in this category.
Flagg, IL Window Replacement FAQs
What is the typical cost to install windows in a home?
The typical cost of replacing one window can range between $450 and $650. There are several factors that influence the price, which include the number of windows, local labor costs, how energy-efficient the windows are, the materials used in designing the windows, your property's location and styles and sizes of windows.
What are the most common types of replacement windows?
There are various types of windows you can get for your house, including double-hung and single-hung windows, transom windows, casement windows, slider windows, picture windows, awning windows and bay windows.
Can I replace my own windows?
If you're handy and have experience with installing a replacement window, you may be able to install your own windows. But if you don't have the time or skills, we recommend getting a professional to do it for you.
When is the best time of year to replace windows?
Although you can install windows any time of year, warmer weather is typically better for replacing windows. In addition, it shouldn't be raining, because rain can make the installation more difficult.
Should I replace my windows all at the same time?
If you want to get more efficient windows and save money on your energy bills, replacing all your windows at the same time is the only way to gain that benefit. On the other hand, if you have just a few windows that are damaged or leaky, you can replace just those.