20 Best Window Companies in Diamond Bar, CA (2023 Reviews)
When it's time to upgrade your windows, our guide to the top window installation companies can help you find the right provider for you.
We analyzed all the top-rated window companies in Diamond Bar and selected the best 20 based on:
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Customer reviews
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Window installation expertise
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Popularity with home-owners like you
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Updated September 15, 2023
Why you can trust EcoWatch
A review of the top window installation companies in Diamond Bar may not seem like the most interesting article on the EcoWatch site, but trust us, windows have more of an impact on your life than you might realize. During the hot summer months, the last thing you want is your cool air to leak out of your outdated windows.
Replacement windows improve the insulation in your home, not only making you more comfortable during extreme temperatures, but also saving you some money and helping the environment.
Efficient windows are of particular importance in Diamond Bar, where summers are long and hot. According to Energy Star, switching to energy-efficient windows can save the average homeowner up to $509 each year.
Best Availability
Renewal by Andersen
- Great industry reputation
- Member of US Green Building Council
- Manufactures products in-house
Window Veteran
Window World
- EnergyStar Partner
- Wide variety of products and services
- Lifetime Warranty
Best Window Installation & Replacement Companies in Diamond Bar
The EcoWatch Reviews team researched dozens of installers in Diamond Bar to find the best window installation companies for our readers. The companies mentioned in this article scored the best in our review categories, such as energy-efficient offerings, availability, price, customer service, local expertise and more.

Window World
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EnergyStar Partner
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Large serice area
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Low prices relative to competitors
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Great industry reputation
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Lifetime warranty
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Quality of service will depend on your area
Window World is the largest window replacement company in the country, known for its vinyl windows and affordability. Window World has been in the window industry for around 27 years.
If you’re looking for a company that is certified by the Environmental Protection Agency (EPA) and Energy Star and supports charities like St. Jude Children’s Research Hospital, Window World may be the right provider for you.
Energy Efficiency of Window World WindowsIts high-performance Low-E (low-emissivity) coatings and argon gas insulation offer exceptional efficiency and performance for any home. Not all of Window World’s windows are Energy Star certified, so be sure to mention that you want Energy Star windows when inquiring.
How much does Window World cost in Diamond Bar?Prices aren’t listed 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 pricing information is to get a free quote from the company.

Milgard Windows & Doors
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EnergyStar Partner
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Wide network of installers
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Lifetime warranty available
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Entails hiring third-party contractors
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Limited additional services
Milgard Windows & Doors is a family-owned and -operated window replacement company, which primarily serves the West Coast. This window installation company has been operating since 1962 and currently services Anaheim, Riverside, Los Angeles, San Bernardino and Orange counties. Its reputation is backed by several positive reviews on customer review websites.
You may want to consider choosing Milgard if you're looking for a installer 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 WindowsMilgard Windows & Doors’s commitment to sustainability can be seen in its 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 Diamond Bar?Pricing information is not available on Milgard’s website since the cost of window installment depends on how many and what type(s) of windows you need. However, it offers different kinds of windows at varying price points. You can ask for a free quote on its website for more information about the cost.

Renewal by Andersen
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Great industry reputation
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Award-winning company
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Member of US Green Building Council
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Manufactures products in-house
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No lifetime warranty
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More expensive than competition
Renewal by Andersen is a subsidiary of the Andersen Corporation, a major manufacturer of windows and doors. This window installation company has been operating since 1995 and currently services nearly every state except Mississippi and West Virginia. Its reputation is backed by several positive reviews on customer review websites.
You may want to consider choosing Andersen if you're looking for a installer 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 WindowsRenewal by Andersen’s commitment to sustainability can be seen in its 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 Diamond Bar?Pricing information is not available on Andersen’s website since the cost of window installment depends on how many and what type(s) of windows you need. However, based on customer feedback, you can expect to pay anywhere between $750 to $1,250 per window for an installation with Andersen. You can ask for a free quote on its website for more information about the cost.

Universal Windows Direct
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Makes charitable contributions
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Manufactures products in-house
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Wide variety of products and services
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Lifetime warranty
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Limited service area
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Some installations carried out by third-party contractors
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Quality of service will depend on your area
Universal Windows Direct is a company that has grown immensely since its inception in 2002, and now has several franchise dealers nationwide. This company has been operating since 2002 and currently serves 27 states nationwide. Its reputation is backed by hundreds of positive reviews from customers online.
It has established itself as a company that has an industry-leading warranty covering products, parts and workmanship for life.
Energy Efficiency of Universal Windows Direct WindowsThe 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. Not all of Universal’s offerings are Energy Star certified, so be sure to mention that you’d like Energy Star windows when inquiring.
How much does Universal Windows Direct cost in Diamond Bar?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 receive a free quote from the company.
We try to remain unbiased and transparent by mentioning pros and cons for every company we review. Additionally, our rankings are not affected by any partnerships.
More Window Companies in Diamond Bar
Renewal by Andersen of Orange County
Laguna Hills, CA-
Good Customer Service
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Price Transparency
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Educational Website
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Free assessment
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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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Stained Glass
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Commercial Windows
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Fast Delivery
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Sliding Glass
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Window Replacement
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Double-Hung
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Residential Windows
Window World of Los Angeles
Covina, CA-
Educational Website
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Price Transparency
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Free assessment
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Good Customer Service
Services Offered
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Custom Window Designs
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Fast Delivery
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Residential Windows
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Bay Windows
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Window Replacement
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Double-Hung
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Sliding Glass
J. R. Door & Window Inc
Upland, CA-
Price Transparency
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Good Customer Service
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Educational Website
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Free assessment
Services Offered
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Fast Delivery
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Residential Windows
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Window Replacement
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Commercial Windows
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Custom Window Designs
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Aluminum Window Frames
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Double-Hung
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Sliding Glass
American Window Company
Covina, CA-
Educational Website
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Good Customer Service
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Free assessment
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Price Transparency
Services Offered
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Custom Window Designs
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Energy-Efficient Options
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Aluminum Window Frames
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Residential Windows
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Double-Hung
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Window Replacement
Design Windows and Doors Inc.
Ontario, CA-
Price Transparency
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Timely Service
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Good Customer Service
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Free assessment
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Educational Website
Services Offered
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Commercial Windows
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Energy-Efficient Options
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Bay Windows
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Residential Windows
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Double-Hung
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Window Replacement
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Custom Window Designs
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Aluminum Window Frames
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Sliding Glass
Dreamstyle Remodeling
Irwindale, CA-
Educational Website
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Price Transparency
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Good Customer Service
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Free assessment
Services Offered
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Glass Showers
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Window Replacement
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Bay Windows
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Custom Window Designs
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Fast Delivery
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Sliding Glass
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Double-Hung
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Residential Windows
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Full-Service Installations
SoCal Window Pros
San Dimas, CA-
Good Customer Service
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Free assessment
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Educational Website
Services Offered
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Residential Windows
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Window Replacement
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Custom Window Designs
Home Services at The Home Depot
Ontario, CA-
Educational Website
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Free assessment
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Good Customer Service
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Price Transparency
Services Offered
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Commercial Windows
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Glass Showers
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Window Replacement
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Stained Glass
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Custom Window Designs
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Fast Delivery
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Residential Windows
Emerald Mirror & Glass
Yorba Linda, CA-
Free assessment
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Educational Website
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Good Customer Service
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Price Transparency
Services Offered
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Window Repair
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Commercial Windows
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Custom Window Designs
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Window Replacement
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Glass Showers
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Residential Windows
Advance Windows & Doors
Walnut, CA-
Free assessment
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Educational Website
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Price Transparency
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Good Customer Service
Services Offered
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Fast Delivery
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Tempered Glass
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Double-Hung
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Commercial Windows
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Bay Windows
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Window Replacement
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Residential Windows
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Custom Window Designs
NagcoGlass
Pomona, CA-
Free assessment
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Price Transparency
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Good Customer Service
Services Offered
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Residential Windows
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Glass Showers
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Custom Window Designs
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Window Replacement
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Commercial Windows
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Energy-Efficient Options
Molding's Plus Inc
Ontario, CA-
Free assessment
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Good Customer Service
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Price Transparency
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Educational Website
Services Offered
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Window Replacement
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Custom Window Designs
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Residential Windows
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Fast Delivery
JK Glass & Mirror Inc
Baldwin Park, CA-
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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Custom Window Designs
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Window Replacement
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Glass Showers
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Residential Windows
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Commercial Windows
N.E.U GLASS WINDOW REPAIR
La Puente, CA-
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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Custom Window Designs
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Window Replacement
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Residential Windows
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Double-Hung
Sears Window Replacement
Montclair, CA-
Free assessment
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Good Customer Service
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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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Residential Windows
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Fast Delivery
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Window Replacement
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Bay Windows
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Sliding Glass
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Energy-Efficient Options
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Custom Window Designs
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Double-Hung
Energy Core Construction
Anaheim, CA-
Price Transparency
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Timely Service
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Free assessment
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Good Customer Service
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Educational Website
Services Offered
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Custom Window Designs
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Residential Windows
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Aluminum Window Frames
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Energy-Efficient Options
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Sliding Glass
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Commercial Windows
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Window Replacement
A New View Windows & Doors Inc.
Anaheim, CA-
Timely Service
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Price Transparency
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Good Customer Service
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Educational Website
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Free assessment
Services Offered
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Double-Hung
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Fast Delivery
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Glass Showers
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Custom Window Designs
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Window Replacement
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Commercial Windows
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Energy-Efficient Options
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Residential Windows
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Sliding Glass
All Cities Glass & Screen
Glendora, CA-
Educational Website
Services Offered
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Residential Windows
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Commercial Windows
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Window Replacement
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Glass Showers
Cal Replacement Window Company of Orange County
Anaheim, CA-
Price Transparency
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Educational Website
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Free assessment
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Good Customer Service
Services Offered
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Full-Service Installations
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Double-Hung
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Bay Windows
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Window Replacement
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Custom Window Designs
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Sliding Glass
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Residential Windows
Dede Windows and Doors
Anaheim, CA-
Educational Website
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Good Customer Service
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Free assessment
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Price Transparency
Services Offered
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Sliding Glass
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Residential Windows
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Energy-Efficient Options
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Window Replacement
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Double-Hung
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Custom Window Designs
Calculate how much you can expect to pay for window installation and replacement in Diamond Bar, CA using our customized window cost calculator.
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 Diamond Bar Saves You Money
Energy-efficient windows can benefit you in more than one way. Here are some reasons you may want to think about making the switch:
- Protect your valuables: The low-emissivity coatings on many Energy Star certified windows help reduce damage from the sun's UV rays to your floors, carpets and furniture.
- Save money on energy bills: The Department of Energy estimates that heat gained or lost via windows accounts for around 25-30% of energy use in your home. Switching to energy-efficient windows can help lower that amount, which helps you save some money on your bills.
- Protect your investment: If you have a relatively old home, your windows are most likely outdated. Updating your windows can make your home more comfortable and also help increase the value of your home if you decide to sell.
- Better temperature control in your home: Energy-efficient windows can decrease how hard your heating system needs to work to heat your home.
Estimated Cost of Window Replacement in Diamond Bar
Windows come in various shapes, purposes and styles, so costs and services will vary remarkably based on several factors. Below, we describe the average cost and services that you can get from window installation companies.
How Much Do New Windows Cost?
The national average cost to install a single window is about $600 but can range from $200 to $1,200. How much it will cost you depends on several factors, like size, number of windows, type, material, the location of your home and more.
It's also worth noting that energy-efficient windows will usually cost more upfront, but Energy Star estimates that switching out the windows on your Diamond Bar home can mean an average energy savings of $236 to $319 a year for single-pane window replacement, or between $87 to $126 a year for double-pane windows. How much you'll save by switching to energy-efficient windows depends on your local climate, energy rates and other factors unique to your home.
Asking for free quotes from several installers is the best way to find out which one will work best for your budget.
What Services do Window Installers Offer?
The first step of an installation is to think about whether you should get a full-frame or pocket installation.
Full-frame installations are usually recommended when you want to change the style of your windows or your window has significant rot or deterioration. With this service, your installers will replace the full window, including the trim, sill and frame. Pocket installations are on the simpler end and won't carry as large a bill because they entail simply replacing the window within its existing frame. But if the frame has any damage, you may have to get a full-frame installation instead.
Your window installation company should be able to help you decide which type of installation you should get.
Best Availability
Renewal by Andersen
- Great industry reputation
- Member of US Green Building Council
- Manufactures products in-house
Window Veteran
Window World
- EnergyStar Partner
- Wide variety of products and services
- Lifetime Warranty
How We Choose the Best Window Installers in Diamond Bar
In our search to make your home improvements easier and more eco-friendly in Diamond Bar, the EcoWatch Reviews team assessed many companies before settling on these. Along with energy efficiency, we assessed each installer and assigned rankings using the following methodology:
Service Area
This one is self-explanatory, but we've chosen to highlight window installers that serve a wide variety of states and cities so you can find a quality window installation company near you.
Work Quality
We're certain that you're looking for professionals who do a great job installing windows. We've vetted each installer in our guide to ensure its contractors are well-qualified and that the company has received a lot of positive customer feedback to vouch for its service.
Customer Reviews
We analyzed trends in recent online reviews to determine the companies with the most customer satisfaction, weighted by sample size. Customer satisfaction might be the factor we place the most value on, as it reflects the quality of services across most other categories, including quality of parts, quality of installation, cost, warranty, professionalism and more.
Cost
This one is a give-and-take: similar to most services, cheap window companies are not going to provide the most quality service. On the other hand, we want to ensure we're highlighting companies that offer a variety of price and financing options so they're accessible to most homeowners.
Warranty
As discussed previously, windows are a hefty investment, so you'll want to be certain that investment is well protected. Window installation companies that offer lengthy warranties for products, parts and labor rank higher with EcoWatch.
Years of Experience
Last but not least, we like to see companies that have been in the industry for a while. Window installation companies that have more years of experience earn higher rankings by our standards. We like to see at least ten years of experience.
Diamond Bar, CA Window Replacement FAQs
What is the typical cost to install new windows in a home?
The national average cost of installing one window is about $600 but can range between $200 and $1,200, depending on several factors. The price is often influenced by the location of your property, the size of the window and the type and material of the window. Also, bear in mind that energy-efficient windows may cost more upfront but can save you hundreds of dollars a year in energy bills.
Which kind of window is the best?
Generally, double-pane windows are more efficient than single-pane windows and windows that don't open are more efficient than windows that do. If you want to be sure you'll get the most energy-efficient windows, look for models with the blue Energy Star certification — this means they're certified energy-efficient by the U.S. Department of Energy.
What do window installers do?
Window installers visit your home to remove your old windows and replace them with new ones. Some providers install products distributed by other companies, whereas others install their own windows. The installer will also clean up after the installation.
Should I replace my windows all at once?
If you're upgrading your windows to save on your energy bills, replacing all your windows at the same time is the only way to gain that benefit. However, if you have only one or two windows that are broken or leaky, you can replace just those.