20 Best Window Companies in Windsor, CA (2024 Reviews)

Looking to improve your property’s insulation? The best window replacement companies can help.

We analyzed all the top-rated window companies in Windsor and selected the best 20 based on:

  • Customer reviews
  • Window installation expertise
  • Popularity with home-owners like you
EcoWatch Local Advisors

By EcoWatch Local Advisors

Updated February 01, 2024

Why you can trust EcoWatch

Our panel of energy experts work tirelessly to create unbiased reviews and informative content to help homeowners make educated decisions. No other windows site has covered energy efficiency and sustainability as long as EcoWatch, which means we're going to help you find windows replacements that will save on your energy bill and put more money back in your wallet.

Whether you're updating for aesthetics or have old windows, windows play a vital role in conserving your home's energy. Poor windows can cut your home’s energy efficiency by up to 30%, according to the Department of Energy. In Windsor, that’s around $418 a year that you could save on your power bills by making the switch.

Installing efficient windows on your house can help you save money each month on your power bills — and you can help the environment, too.

As windows are so important for your home, selecting the right company for you is a big decision to make. That’s why the EcoWatch team has made this list of the best window installation companies, so you can make an informed decision more easily.

Best Availability

Renewal by Andersen

★★★★★
4.5
  • Great industry reputation
  • Member of US Green Building Council
  • Manufactures products in-house
Buy One Window, Get One 40% OFF
Get Estimate

Best Energy-Efficient Features

Champion

★★★★★
4.5
  • Many years of experience
  • Low prices relative to competitors
  • Limetime warranty
Buy 2 Windows, Get 2 Free
Get Estimate

Power Home

★★★★★
4.5
  • Uses eco-friendly materials
  • Well-trained, certified installers
  • Lifetime or lengthy warranty
Next-Day Appointments Available
Get Estimate

Best Window Installation & Replacement Companies in Windsor

The EcoWatch team assessed dozens of installers in Windsor to find the top window installation companies for our readers. The installers in this article passed our review standards for energy-efficient offerings as well as customer service, price, local expertise and beyond.

Window World logo
FAST QUOTE
as little as 30 seconds
Best Affordability

Window World

★★★★★
BBB Rating: A+
Locations: Nationwide
Founded: 1995
Pros:
  • Pros icon EnergyStar Partner
  • Pros icon Large serice area
  • Pros icon Low prices relative to competitors
  • Pros icon Great industry reputation
  • Pros icon Lifetime warranty
Cons:
  • Pros icon Quality of service will depend on your area

Window World offers windows expertise in Windsor. It's the largest window replacement company in the country, known for its vinyl windows and affordability. This company has been in business since 1995 and currently serves 200 locations nationwide.

Window World may be the company for you if you want one 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 Windows

Window World appeals to eco-conscious consumers by providing energy-efficient window offerings. 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 Windsor?

Prices aren’t displayed on Window World’s website, but it's known for offering some of the most affordable window installations around. The best way to get more accurate information is to get a free quote from the company.

Milgard Windows & Doors logo
FAST QUOTE
as little as 30 seconds
Excellent Reputation

Milgard Windows & Doors

★★★★★
BBB Rating: A
Locations: West Coast
Founded: 1962
Pros:
  • Pros icon EnergyStar Partner
  • Pros icon Wide network of installers
  • Pros icon Lifetime warranty available
Cons:
  • Pros icon Entails hiring third-party contractors
  • Pros icon Limited additional services

Milgard Windows & Doors offers the best local installation in Windsor. It's a family-owned and -operated window replacement company, which primarily serves the West Coast. This company has been in business since 1962 and currently serves Anaheim, Riverside, Los Angeles, San Bernardino and Orange counties.

Milgard may be the company for you if you want one that offers competitive pricing, a comprehensive warranty and installers that all have a minimum of 15 years of window installation experience.

Energy Efficiency of Milgard Windows & Doors Windows

Milgard Windows & Doors appeals to eco-conscious consumers by providing energy-efficient window offerings. The company manufactures its own products, which gives it the freedom to make custom windows based on the climate. The company designs its own vinyl compounds and profiles to ensure a heat-stable product that performs as advertised.

How much does Milgard Windows & Doors cost in Windsor?

Prices aren’t displayed on Milgard’s website, but it offers different kinds of windows at varying price points. The best way to get more accurate information is to get a free quote from the company.

Renewal by Andersen logo
FAST QUOTE
as little as 30 seconds
Best Overall

Renewal by Andersen

★★★★★
BBB Rating: A
Locations: Nationwide
Founded: 1995
Pros:
  • Pros icon Great industry reputation
  • Pros icon Award-winning company
  • Pros icon Member of US Green Building Council
  • Pros icon Manufactures products in-house
Cons:
  • Pros icon No lifetime warranty
  • Pros icon More expensive than competition

Renewal by Andersen offers the best availability in Windsor. It's a subsidiary of the Andersen Corporation, a major manufacturer of windows and doors. This company has been in business since 1995 and currently serves nearly every state except Mississippi and West Virginia.

Andersen may be the company for you if you want one that uses in-home estimates and advanced digital tools to help you plan and visualize your project before getting started.

Energy Efficiency of Renewal by Andersen Windows

Renewal by Andersen appeals to eco-conscious consumers by providing energy-efficient window offerings. 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 Windsor?

Prices aren’t displayed on Andersen’s website, but based on customer feedback, you can expect to pay anywhere between $750 to $1,250 per window for an installation with Andersen. The best way to get more accurate information is to get a free quote from the company.

Universal Windows Direct logo
FAST QUOTE
as little as 30 seconds
Best Warranty

Universal Windows Direct

★★★★★
BBB Rating: A
Locations: Nationwide
Founded: 2002
Pros:
  • Pros icon Makes charitable contributions
  • Pros icon Manufactures products in-house
  • Pros icon Wide variety of products and services
  • Pros icon Lifetime warranty
Cons:
  • Pros icon Limited service area
  • Pros icon Some installations carried out by third-party contractors
  • Pros icon Quality of service will depend on your area

Universal Windows Direct offers the best warranty in Windsor. It's a company that has grown immensely since its inception in 2002, and now has several franchise dealers nationwide. This company has been in business since 2002 and currently serves 27 states nationwide.

Universal may be the company for you if you want one that has an industry-leading warranty covering products, parts and workmanship for life.

Energy Efficiency of Universal Windows Direct Windows

Universal Windows Direct appeals to eco-conscious consumers by providing energy-efficient window offerings. 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 Windsor?

Prices aren’t displayed 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. The best way to get more accurate information is to get a free quote from the company.

We have tried to stay unbiased and transparent by describing pros and cons for every company. Additionally, any partnerships do not affect our reviews.

More Window Companies in Windsor

B & L Glass

Santa Rosa, CA
4.8
★★★★★
  • Pros icon Good Customer Service

Services Offered

  • Service icon Glass Doors
  • Service icon Energy-Efficient Options
  • Service icon Skylights
  • Service icon Mirrors
  • Service icon Window Replacement/Installation
  • Service icon Custom Glass
  • Service icon Glass Showers
  • Service icon Glass Repair

Website: https://blglass.com/
Address: 3175 Cleveland Ave, Santa Rosa, CA 95403
Phone: (707) 546-4143

Santa Rosa Window Tint

Santa Rosa, CA
5.0
★★★★★
  • Pros icon Price Transparency
  • Pros icon Free assessment
  • Pros icon Good Customer Service
  • Pros icon Educational Website

Services Offered

  • Service icon Window Replacement/Installation

Website: http://www.santarosawindowtint.com/
Address: 3721 Santa Rosa Ave b4, Santa Rosa, CA 95407
Phone: (707) 879-8468

Jack Smith Glass & Sash Inc.

Santa Rosa, CA
3.9
★★★★★
  • Pros icon Educational Website
  • Pros icon Price Transparency
  • Pros icon Good Customer Service
  • Pros icon Free assessment

Services Offered

  • Service icon Custom Window Designs
  • Service icon Mirrors
  • Service icon Wood Frames
  • Service icon Window Repair
  • Service icon Window Replacement/Installation
  • Service icon Skylights
  • Service icon Glass Showers
  • Service icon Glass Doors

Website: http://www.jacksmithglass.com/
Address: 1050 N Dutton Ave, Santa Rosa, CA 95401
Phone: (707) 544-0640

GreenRun Construction - General Contractors

Santa Rosa, CA
3.4
★★★★★
  • Pros icon Price Transparency
  • Pros icon Free assessment
  • Pros icon Good Customer Service
  • Pros icon Educational Website

Services Offered

  • Service icon Vinyl Frames
  • Service icon Glass Showers
  • Service icon Window Replacement/Installation
  • Service icon Bay Windows

Website: http://www.greenrunusa.com/
Address: 2175 Bluebell Dr Suite E, Santa Rosa, CA 95403
Phone: (707) 812-7006

Denton's Glass Co.

Santa Rosa, CA
3.1
★★★★★
  • Pros icon Price Transparency
  • Pros icon Free assessment
  • Pros icon Educational Website
  • Pros icon Good Customer Service

Services Offered

  • Service icon Energy-Efficient Options
  • Service icon Glass Showers
  • Service icon Window Replacement/Installation
  • Service icon Mirrors
  • Service icon Glass Doors

Website: https://dentonsglass.com/
Address: 957 W College Ave, Santa Rosa, CA 95401
Phone: (707) 708-0798

Northwest Exteriors

Santa Rosa, CA
3.1
★★★★★
  • Pros icon Educational Website
  • Pros icon Free assessment
  • Pros icon Price Transparency
  • Pros icon Timely Service

Services Offered

  • Service icon Vinyl Frames
  • Service icon Window Replacement/Installation

Website: http://www.northwestexteriors.com/
Address: 3450 Airway Dr STE G, Santa Rosa, CA 95403
Phone: (707) 527-7770

Dee Jay's Sash & Glass, Inc.

Santa Rosa, CA
3.0
★★★★★
  • Pros icon Free assessment
  • Pros icon Price Transparency
  • Pros icon Good Customer Service

Services Offered

  • Service icon Mirrors
  • Service icon Skylights
  • Service icon Window Replacement/Installation
  • Service icon Glass Showers

Website: http://www.deejaysglass.com/
Address: 2985 Wiljan Ct, Santa Rosa, CA 95407
Phone: (707) 546-7344

Pella Windows & Doors of Northern California

Rohnert Park, CA
3.2
★★★★★
  • Pros icon Educational Website
  • Pros icon Free assessment
  • Pros icon Good Customer Service
  • Pros icon Price Transparency

Services Offered

  • Service icon Double-Hung
  • Service icon Bay Windows
  • Service icon Window Replacement/Installation
  • Service icon Glass Doors

Website: http://www.pellanorcal.com/
Address: 5430 Commerce Blvd #1b, Rohnert Park, CA 94928
Phone: (707) 394-5886

Nor Cal Glass Products

Rohnert Park, CA
3.0
★★★★★
  • Pros icon Good Customer Service
  • Pros icon Price Transparency

Services Offered

  • Service icon Glass Showers
  • Service icon Glass Doors
  • Service icon Mirrors
  • Service icon Bay Windows
  • Service icon Window Replacement/Installation

Website: http://www.norcalglassproducts.com/
Address: 566 Martin Ave A, Rohnert Park, CA 94928
Phone: (707) 206-9660

Home Services at The Home Depot

Rohnert Park, CA
2.7
★★★★★
  • Pros icon Educational Website
  • Pros icon Free assessment
  • Pros icon Good Customer Service
  • Pros icon Price Transparency

Services Offered

  • Service icon Glass Doors
  • Service icon Glass Showers
  • Service icon Window Replacement/Installation
  • Service icon Custom Window Designs
  • Service icon Bay Windows
  • Service icon Screen Repair
  • Service icon Energy-Efficient Options
  • Service icon Vinyl Frames
  • Service icon Storm/Impact Windows

Website: https://www.homedepot.com/l/Rohnert-Pk/CA/Rohnert-Park/94928/641/services
Address: 4825 Redwood Dr, Rohnert Park, CA 94928
Phone: (707) 296-1203

The Window Design Studio

Petaluma, CA
3.0
★★★★★
  • Pros icon Price Transparency
  • Pros icon Good Customer Service
  • Pros icon Free assessment
  • Pros icon Educational Website

Services Offered

  • Service icon Bay Windows
  • Service icon Window Replacement/Installation
  • Service icon Energy-Efficient Options
  • Service icon Custom Window Designs

Website: https://thewindowdesignstudio.com/
Address: 280 Monte Vista Ln, Petaluma, CA 94952
Phone: (415) 877-5492

American Window Systems, Inc.

Napa, CA
4.7
★★★★★
  • Pros icon Good Customer Service
  • Pros icon Free assessment
  • Pros icon Price Transparency
  • Pros icon Educational Website

Services Offered

  • Service icon Window Replacement/Installation
  • Service icon Skylights

Website: https://www.amwinsys.com/
Address: 1729 Action Ave suite b, Napa, CA 94559
Phone: (707) 244-7260

Novato Glass Inc

Novato, CA
4.4
★★★★★
  • Pros icon Price Transparency
  • Pros icon Good Customer Service
  • Pros icon Free assessment
  • Pros icon Educational Website

Services Offered

  • Service icon Skylights
  • Service icon Window Replacement/Installation
  • Service icon Glass Doors
  • Service icon Glass Showers
  • Service icon Bay Windows
  • Service icon Custom Glass
  • Service icon Energy-Efficient Options
  • Service icon Mirrors

Website: http://novatoglassinc.com/
Address: 1020 Reichert Ave, Novato, CA 94945
Phone: (415) 897-5117

Window Factory

Greenbrae, CA
4.9
★★★★★
  • Pros icon Educational Website
  • Pros icon Free assessment
  • Pros icon Good Customer Service

Services Offered

  • Service icon Vinyl Frames
  • Service icon Metal Frames
  • Service icon Fiberglass Frames
  • Service icon Window Replacement/Installation
  • Service icon Wood Frames
  • Service icon Bay Windows
  • Service icon Glass Doors

Website: http://www.bayareawindowfactory.com/
Address: 2100 Redwood Hwy, Greenbrae, CA 94904
Phone: (415) 924-3300

The Glass Guru

Fairfield, CA
5.0
★★★★★
  • Pros icon Good Customer Service
  • Pros icon Timely Service
  • Pros icon Educational Website
  • Pros icon Free assessment
  • Pros icon Price Transparency

Services Offered

  • Service icon Energy-Efficient Options
  • Service icon Wood Frames
  • Service icon Storm/Impact Windows
  • Service icon Triple Pane Glass
  • Service icon Fiberglass Frames
  • Service icon Metal Frames
  • Service icon Custom Glass
  • Service icon Screen Repair
  • Service icon Skylights
  • Service icon Glass Showers
  • Service icon Tempered Glass
  • Service icon Window Replacement/Installation
  • Service icon Glass Doors
  • Service icon Glass Repair
  • Service icon Vinyl Frames
  • Service icon Window Repair
  • Service icon Mirrors

Website: https://www.theglassguru.com/fairfield-vacaville-ca/
Address: 1601 Enterprise Dr STE 14, Fairfield, CA 94533
Phone: (707) 348-9539

Old Town Glass

Novato, CA
2.9
★★★★★

    Services Offered

    • Service icon Custom Window Designs
    • Service icon Glass Showers
    • Service icon Skylights
    • Service icon Custom Glass
    • Service icon Window Replacement/Installation

    Website: http://www.otglass.com/
    Address: 700 Grant Ave, Novato, CA 94945
    Phone: (415) 897-0088

    Javco Window & Glass Contractors Inc

    Napa, CA
    2.7
    ★★★★★
    • Pros icon Educational Website
    • Pros icon Free assessment

    Services Offered

    • Service icon Window Replacement/Installation
    • Service icon Custom Glass
    • Service icon Glass Showers
    • Service icon Mirrors
    • Service icon Glass Doors

    Website: https://javcowindowsandglass.com/
    Address: 1900 Yajome St, Napa, CA 94559
    Phone: (707) 252-8338

    Ace Glass Company

    San Francisco, CA
    4.6
    ★★★★★
    • Pros icon Price Transparency
    • Pros icon Free assessment
    • Pros icon Good Customer Service

    Services Offered

    • Service icon Tempered Glass
    • Service icon Bay Windows
    • Service icon Window Replacement/Installation
    • Service icon Glass Doors
    • Service icon Glass Showers
    • Service icon Mirrors
    • Service icon Storm/Impact Windows
    • Service icon Glass Repair
    • Service icon Window Repair

    Website: http://sfaceglass.com/
    Address: 381 11th St, San Francisco, CA 94103
    Phone: (415) 395-0806

    Diablo Custom Screen & Glass

    Concord, CA
    4.6
    ★★★★★
    • Pros icon Free assessment
    • Pros icon Price Transparency
    • Pros icon Good Customer Service
    • Pros icon Educational Website

    Services Offered

    • Service icon Bay Windows
    • Service icon Window Replacement/Installation
    • Service icon Custom Glass
    • Service icon Glass Showers

    Website: http://www.diabloscreen.com/
    Address: 1065 Shary Cir, Concord, CA 94518
    Phone: (925) 689-1100

    Vallejo Glass Inc.

    Vallejo, CA
    3.3
    ★★★★★
    • Pros icon Free assessment
    • Pros icon Good Customer Service

    Services Offered

    • Service icon Glass Doors
    • Service icon Mirrors
    • Service icon Glass Repair
    • Service icon Bay Windows
    • Service icon Vinyl Frames
    • Service icon Window Replacement/Installation
    • Service icon Metal Frames
    • Service icon Custom Glass
    • Service icon Energy-Efficient Options
    • Service icon Glass Showers

    Website: https://vallejoglass.com/
    Address: 205 Couch St, Vallejo, CA 94590
    Phone: (707) 644-4447
    Windsor Window Cost Calculator

    Calculate how much you can expect to pay for window installation and replacement in Windsor, CA using our customized window cost calculator.

    Estimated Window Cost:
    161 homeowners have requested a free estimate in the last 3 days.

    Estimates will vary based on window dimensions and other unique factors to your home. Getting in touch with a local window installer is the best way to get an accurate cost estimate for your home.

    How Installing Energy-Efficient Windows in Windsor Saves You Money

    Energy-efficient windows can benefit you in more than one way. Here are some reasons you may want to make the switch:

    • Protect your valuables: Many energy-efficient windows have low-emissivity coatings, which filter out harmful UV rays, reducing fading of your furniture, carpet and other valuables.
    • Protect your investment: When your home is on the older side, your windows could also be outdated or leaky. Upgrading and repairing your windows is an important part of maintaining your property and its value.
    • Save on power bills: Installing energy-efficient windows lowers your energy bills by about 12% because you use less energy.
    • Decrease your carbon footprint: You can reduce your indirect greenhouse gas emissions by about 12% after you install Energy Star certified windows. In Windsor, that’s about 117 pounds per year on average.

    Estimated Cost of Window Replacement in Windsor

    Each window replacement company offers various services and has varying costs based on several factors.

    How Much Do New Windows Cost?

    According to our market research, the average cost to replace a single window is around $600. However, window replacement costs can range from $200 to $1,200 per window. But costs will vary considerably depending on your location, the number of windows you need, the quality of your products and the current condition of your home. A lot of window companies also offer door installations and other add-ons like coating, shutters, baths and more. These extra services will increase overall project costs.

    It’s also worth bearing in mind that energy-efficient windows will cost more initially, but Energy Star estimates that switching out the windows on your Windsor home can mean an average energy savings of $236 to $319 a year for single-pane window replacement, or between $87 to $126 each year for double-pane windows. The amount of money you’ll save by switching to energy-efficient windows depends on your local climate, energy rates and other factors unique to your home.

    Costs will also vary depending on the material you pick for your window frames. Aluminum frames cost the least. They’re sturdy, light and maintenance-free, but offer poor insulation. Vinyl frames are a bit more expensive and offer good insulation. Composite frames made using wood fibers encased in plastic also provide good insulation and are moderately expensive. Wood frames are the most expensive and are the most in-demand. They’re also aesthetically pleasing and offer decent insulation for your home.

    What Services do Window Installers Offer?

    In general, there are two types of window replacement services you can get: full-frame and pocket installations.

    A full-frame installation is a replacement of the total window. It involves taking out the old window, the windowsill, and the exterior and interior trim. It can also involve additional materials, including insulation and drip edges, which increase the overall cost of the project. Also worth noting: you may have to touch up the paint around the window after a full-frame installation. A pocket installation means replacing a window within the existing frame, which is usually cheaper than a full-frame installation.

    If you’re still trying to decide which type of installation to get, you can consult with your installer and get their advice. The decision mostly is influenced by the age of your window frames and if there’s any damage.

    Best Availability

    Renewal by Andersen

    ★★★★★
    4.5
    • Great industry reputation
    • Member of US Green Building Council
    • Manufactures products in-house
    Buy One Window, Get One 40% OFF
    Get Estimate

    Best Energy-Efficient Features

    Champion

    ★★★★★
    4.5
    • Many years of experience
    • Low prices relative to competitors
    • Limetime warranty
    Buy 2 Windows, Get 2 Free
    Get Estimate

    Power Home

    ★★★★★
    4.5
    • Uses eco-friendly materials
    • Well-trained, certified installers
    • Lifetime or lengthy warranty
    Next-Day Appointments Available
    Get Estimate

    How We Choose the Best Window Installers in Windsor

    In our hunt to make your home improvements easier and more eco-friendly in Windsor, the EcoWatch team chose the above companies as the top window installation companies in the city. We have decided to review the top window installation companies in Windsor primarily based on their energy efficient offerings, as it’s what’s best for the environment and for you as a homeowner. Energy-efficient windows have been shown to lower energy bills by hundreds of dollars. Along with energy efficiency, our rating methodology is based on the following factors:

    Service Area

    This one is self-explanatory, but we’ve chosen to highlight window installation companies that serve a wide variety of states and cities so you can find the right window installation company near you.

    Work Quality

    We’re willing to bet that you’re looking for professionals who do a great job installing windows. We’ve vetted each installer included in our guide to make sure its contractors are well-qualified and that the company has gotten a lot of positive customer feedback to vouch for its service.

    Customer Reviews

    Customer feedback is another super important review factor. If the majority of customers don’t have nice feedback about their experience with a certain company, it won’t be featured on EcoWatch.

    Cost

    This one is a give-and-take: similar to other services, cheap window companies are not going to provide the most quality service. On the other hand, we want to make sure we’re highlighting companies that offer a wide range of price and financing options so they’re accessible to most homeowners.

    Warranty

    As discussed previously, windows are a considerable investment, so you’ll want to be certain that investment is protected. Window installation companies that provide lengthy warranties for products, parts and installation (aka workmanship) rank higher with EcoWatch.

    Years of Experience

    Because of Windsor’s climate, homeowners will want to mitigate water damage, low efficiency and rot. We factored in local experience to reflect the ability of Windsor window companies to prepare homes for these issues. If a company has less than 10 years of experience, it loses points in this category.

    Windsor, CA Window Replacement FAQs

    How much does window installation cost?

    The average cost of installing one window ranges from $450 to $650. There are a variety of factors that affect the cost, such as your property’s location, how energy-efficient the windows are, styles and sizes of windows, the materials used in designing the windows, local labor costs and the number of windows.

    What are the types of windows?

    There are several different types of windows you can get for your house, including double-hung and single-hung windows, awning windows, transom windows, picture windows, casement windows, slider windows and bay windows.

    Do I really have to use a window installation company?

    Unless you have home repair skills and have the time to replace your own windows, we recommend hiring the pros. The process of installing windows is complicated and can take anywhere from four to six hours for a single window. Although it’s tempting to try to do it yourself to save money, hiring a company is a faster, more efficient and safer alternative.

    When is the best time of year to replace windows?

    Replacement windows can be installed at any time, but warmer weather is typically better. Regardless of when you install them, the contractors will take steps to make sure that too much hot or cold air doesn’t get into your house, so the temperature outside doesn’t necessarily matter that much. Most importantly, the weather should be dry.

    How long does it generally take to install windows?

    Each window takes around 30 minutes to install based on the type of window. However, the window installation can take two days or more if you need to have a lot of windows installed.