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Best Window Replacement Companies in Longmont, CO

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Written By Max Peterson | Last Updated: February 05, 2024

You might be installing replacement windows to upgrade your home's exterior facade, lower your energy usage, or protect your home from the rain and gusty winds. Local contractors recognize that homeowners would prefer not to pay a pretty penny for window replacement in Longmont. They work with cost-efficient materials that don't sacrifice durability.

Top Pick
  • Full-service installation
  • Large window selection
  • Nearly 30 years of experience
Best Financing
  • Full-service installation
  • In-house, U.S.-made products
  • More than 70 years of experience
Most Customizable
  • Full-service remodeling
  • 96% satisfaction rate
  • More than 30 years of experience

Top 10 Longmont Window Installation Companies

We recommend working with one of these premier companies for your window replacement in Longmont.

Longmont residents can trust the This Old House Reviews Team to provide relevant and up-to-date window company recommendations in their area. To determine which installers are the best, we focus on these five criteria:

  • Services and warranties
  • Professional experience and licensure
  • Product quality
  • Energy-efficiency guarantees
  • Customer reviews and recommendations

Champion Replacement Windows of Ft. Collins Logo

Champion Replacement Windows of Ft. Collins

Based on 777 customer reviews.

Services Offered

Window Replacement/installation Bay Windows Double-Hung Glass Doors


  • Good customer service
  • Price transparency
  • Free assessment
5850 Byrd Dr, Loveland, CO 970-744-2604 championwindow.com
Champion Replacement Windows of Denver Logo

Champion Replacement Windows of Denver

Based on 1,557 customer reviews.

Services Offered

Window Replacement/installation Glass Doors Double-Hung Bay Windows


  • Good customer service
  • Free assessment
  • Price transparency
10035 E 40th Ave Suite 400, Denver, CO 303-800-2129 championwindow.com
Power Home Remodeling Logo

Power Home Remodeling

Based on 2,686 customer reviews.

Services Offered

Window Replacement/installation Energy-Efficient Options


  • Good customer service
7304 S Joliet St #100, Centennial, CO 303-357-2484 powerhrg.com
Window World of Denver Logo

Window World of Denver

Based on 342 customer reviews.

Services Offered

Bay Windows Custom Window Designs Energy-Efficient Options Double-Hung Glass Doors Triple Pane Glass Window Replacement/installation


  • Timely service
  • Good customer service
  • Educational website
480 E 76th Ave Bldg 5e, Denver, CO 303-574-9594 windowworldcolorado.com
DaBella Logo


Based on 844 customer reviews.

Services Offered

Glass Doors Double-Hung Window Replacement/installation Vinyl Frames


  • Good customer service
  • Timely service
6600 E Hampden Ave, Denver, CO 720-619-8704 dabella.us
WestPro | Roofing, Siding, Windows Logo

WestPro | Roofing, Siding, Windows

Based on 321 customer reviews.

Services Offered

Glass Doors Skylights Window Replacement/installation Storm/impact Windows


  • Educational website
  • Price transparency
  • Good customer service
1321 Sherman Dr, Longmont, CO 303-834-9236 westproroofing.com
Rocky Mountain Glass & Shower LLC Logo

Rocky Mountain Glass & Shower

Based on 49 customer reviews.

Services Offered

Window Repair Tempered Glass Window Replacement/installation Glass Showers Mirrors Energy-Efficient Options Glass Doors


  • Price transparency
  • Free assessment
  • Good customer service
13631 N 115th St, Longmont, CO 970-347-9710 rmglass.com
Custom Exteriors Logo

Custom Exteriors

Based on 17 customer reviews.

Services Offered

Window Replacement/installation Vinyl Frames Bay Windows Glass Doors


  • Price transparency
  • Educational website
  • Good customer service
18674 Co Rd 3, Berthoud, CO 970-460-8714 customexteriorsllc.com
Window Well Replacement LLC Logo

Window Well Replacement

Based on 16 customer reviews.

Services Offered

Wood Frames Window Replacement/installation


  • Free assessment
  • Good customer service
  • Price transparency
316 E Michigan Ave, Berthoud, CO 720-727-5839 windowwellreplacements.com

More Local Window Companies

Slade Glass Co.

User Reviews: 4.5/5 

504 5th Ave
Longmont, CO 80501

Josh Brooks Construction and Renovation

User Reviews: 4.3/5 

2204 18th Ave Suite 227
Longmont, CO 80503

BlueBird Windows & Doors

User Reviews: 4.8/5 

1200 Diamond Cir Unit J
Lafayette, CO 80026

Glass Doctor Home + Business of Boulder

User Reviews: 4.4/5 

5649 Arapahoe Ave Unit N
Boulder, CO 80303

Ameritech Windows

User Reviews: 5/5 

1310 College Ave #400
Boulder, CO 80302

Smart Windows

User Reviews: 4.6/5 

740 S Pierce Ave # 5
Louisville, CO 80027

To share feedback or ask a question about this article, send a note to our Reviews Team at reviewsteam@thisoldhousereviews.com.

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Facts about Longmont
Annual Energy Efficient Windows Savings: $449
Average Max Temp: 59°F
Average Min Temp: 40°F
Average Daily Sunlight: 60%
Average Annual Snowfall: 72.6"
Average Monthly Precipitation: 1.45"

Expert Tips By

This Old House empowers homeowners with the knowledge and tools they need to tackle various projects and navigate the complexities of homeownership.

How To Choose a Window Company in Longmont

Reliability is key when it comes to choosing a window installer. However, your chosen company should also suit your needs and understand your vision. Keep in mind the following factors during your company search:

Window Cost by Type

When it comes to upgrading your windows, value is most important. Each window you buy should deliver maximum durability at an affordable price point. Choosing economy windows could actually increase your overall cost, due to their reduced lifespan and more intensive maintenance needs. The material, size, and style of your new windows have the greatest impact on your final cost. Simple double-hung windows deliver great value with their straightforward style and simple mechanisms, while new skylights cost more to prepare for and install. It's wise to speak with a reliable installer to decide on your best options.

In this table, you can find cost data for the most common residential window types to determine how much you might pay.

Window Types Average Cost
Arched $216-$1326
Awning $312-$871
Bay $720-$5345
Custom $320-$890
Casement $249-$1445
Double-hung $116-$752
Egress $213-$533
Glass Block $42-$540
Picture $187-$1385
Single-hung $84-$1425
Skylight $106-$1286
Sliding $245-$1247
Storm $50-$352
Transom $261-$546

Window Material Cost

You'll also need to choose a window material. Homeowners usually base their decision on the local climate, energy efficiency objectives and aesthetic preferences. Aluminum windows are perfect for sleek, modern designs, but they cost more up-front. You'll pay less for wood windows up-front, but you'll need to invest in regular maintenance to prevent the frame from warping and wear. Vinyl is readily available and tends to cost less, but don't underestimate its strong durability and low maintenance needs.

Window Types Average Cost
Aluminum $50-$1425
Composite $514-$1156
Fiberglass $84-$720
Vinyl $173-$1603
Wood $257-$1445

Other Window Replacement Costs

Ask each company you're evaluating about warranty fees, labor costs, and permit fees. This will help you gain a complete understanding of the overall expenses involved in the project.

Experience and Training

Select a provider that focuses on window repair and installation, and look for this information on its website:

  • How long it's been serving the Longmont area
  • Photo galleries of completed projects
  • Privately-issued credentials attesting to its workmanship
The more experience a company has, the better its service and workmanship.

Licensing and Credentials

Colorado's contractor licensing requirements are distinct among states. There is no single regulatory body that licenses window companies, but they might still need licenses from local authorities in which they operate. Both Colorado Springs and Denver license window installers, treating them as either general contractors or building contractors. For other areas, check with your local government.

Types of Windows Offered

There are numerous replacement window types you can choose from, and it's important to find a company that focuses on installing the ones you want. Browse a company's website and reviews for any of these types:

  • Awning
  • Bay
  • Bow
  • Casement
  • Crank-out
  • Custom
  • Double- or single-hung
  • Egress
  • Garden
  • Jalousie
  • Picture
  • Sliding
  • Skylight
  • Specialty
  • Storm
  • Transom
  • Vent
Also, check the type of window framing materials a company works with. Each material has distinct price points, life spans, and energy performance capabilities. Common materials include fiberglass, composite, vinyl, aluminum and wood.

Customer Feedback

One of the best ways to vet a company is to see what other customers have said about their experiences. Read customer reviews on sites such as Trustpilot, Yelp, and Google. You can also view customer reviews and company ratings on the Better Business Bureau (BBB) website. Referrals can also help you in your company search. Ask each company you're interested in for a list of references, and talk to family and friends about who they use for window installations.

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Frequently Asked Questions About Window Replacement in Longmont

Why should I hire a professional to install or replace my windows?

By working with an expert, you don't need to worry about measurement missteps or not having the right tools. A window installation crew is well-equipped with the right tools and skills to do the job safely and accurately. You can also get fast, informed answers to your questions and customized assistance to make the most of your new windows

What time of year should I replace my windows?

There is no one-size-fits-all time to update your windows, but some seasons might be better than others depending on the local climate and a company's demand. Longmont experiences intense winters, so consider scheduling your installation for the early summer or late spring.

Can I replace just my windows' glass and not their frames?

If your window has a cracked pane, it might not be required to replace the frame. Usually, only the glass needs to be fixed unless the frame has also taken significant damage. A professional can determine exactly what's necessary during an estimate visit.

To share feedback or ask a question about this article, send a note to our Reviews Team at reviewsteam@thisoldhousereviews.com.

More Window Resources

National Windows Company Ranking Methodology


Energy Star