Bay Windows in St. Louis
installed by your local window contractor with 25+ Years of Reliable Window Installation Services
Stunning bay windows custom-built for your St. Louis home. Infinity by Marvin installation from Replacement Windows by Lakeside.
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Capture Unforgettable Views from Every Angle with Stunning Bay Windows
Are you looking for a window that doubles as a statement piece in a high-traffic room—such as the living room, kitchen, or bedroom—that will also enhance curb appeal by adding undeniable architectural interest to your home?
If so, you’ll fall in love with the elegant style, boost in natural light, and beautiful views provided by bay windows. At Replacement Windows by Lakeside, we specialize in helping homeowners in St. Louis transform their old, dysfunctional windows with attractive, hassle-free windows that fit their family’s needs—and we’d love to help you next!
Lifetime Workmanship Warranty
You can rely on us for excellence in quality, value, and craftsmanship.
- We have an A+ Rating with the Better Business Bureau
- Hundreds of reviews combined with our full exterior company, Lakeside Renovation & Design
- All of our in-house contractors are licensed and insured
- We provide Lifetime Workmanship Warranty on top of Infinity by Marvin’s product warranty
- We offer financing options to work with your budget
An Endless Horizon of Possibility: Customization Options for Your Infinite by Marvin Bay Windows
At Replacement Windows by Lakeside, we specialize in installing premium Infinite by Marvin® windows, made with durable Ultrex® fiberglass. As an Infinite by Marvin Gold Partner, our team is trained to ensure precise installation and can provide expert guidance on selecting the right window options for your home from the following choices:
- Configurations — Choose from bay window layouts with two casement windows and a fixed center unit, or three operable double-hung windows, installed at 30° or 45° to capture the perfect views and ventilation.
- Exterior & Interior Finishes — Find a lasting acrylic color that complements your home’s design, including EverWood®, a finish that looks and feels like natural wood.
- Glass & Divided Lites — Add architectural interest to your home with divided lite patterns, or enhance the durability, soundproofing, and aesthetics of your new bay windows with decorative, performance, or specialty glass.
- Hardware — Select a flawless finishing touch for your bay windows with high-end, stylish hardware options.
Top Benefits of Bay Windows
Vibrant Views
If you want to flood your home with bright natural light, bay windows are an exceptional choice. Since bay windows include three windows in one system, the amount of sunlight they welcome into your home is tripled—not to mention, they offer stunning views from several angles!
Spacious Window Seat
Bay windows protrude outward, generally with one large window at the center and two smaller, angled windows on either side. This configuration adds square footage to your home and creates a window seat that can be used creatively as a reading corner or a breakfast nook.
Eye-Catching Exterior
Bay windows not only enhance the inside of your home. They’re an excellent choice for adding architectural interest to homes of all types—from traditional to contemporary styles. This makes bay windows an outstanding investment for an instant boost in curb appeal!
How Much Does It Cost to Install Bay Windows?
We offer custom window installation, meaning your windows will be tailored to fit your needs, style, and budget. Since window installation is not a “one-size-fits-all” process, here are some cost factors to consider when budgeting for your new bay windows:
- Size: Larger windows with complex configurations, such as bay windows, tend to require more labor and materials. Although this makes them more expensive to install, the cost is almost always worth the instant boost in curb appeal.
- Material: We install windows with top-performance Ultrex fiberglass, which, while more expensive than wood and vinyl, is designed to last a lifetime.
- Style: Your special customizations, from the frame color to hardware selections, impact the overall project cost—but they also make your windows one of a kind!
Our Personalized, Stress-Free Window Installation Process
At Replacement Windows by Lakeside, we pride ourselves on delivering functional, beautiful windows with meticulous, hassle-free installation. Here’s our tried-and-true process that ensures the job is done right—the first time!
First, we meet for a consultation, during which we help choose window configurations, finishes, and hardware that align with your style, budget, and replacement goals.
Next, a member of our team comes to your home to take precise measurements, ensuring your custom-ordered windows are the perfect fit.
On installation day, our in-house team will install your new windows using top-notch water-taping systems and insulated foam to ensure premium performance.
Finally, we’ll conduct a post-installation inspection to ensure you’re thrilled with our work, and we’ll stand behind it with a lifetime workmanship warranty.
See Our Project Featured by Infinity by Marvin!
“Transforming a 1948 Federal-Style Home with Infinity Replacement Windows
To preserve the home’s traditional style, the homeowners selected traditional divided lite patterns and a classic color selection to preserve the home’s historic charm. Infinity’s flexible design options allowed the Lakeside team to match the original style while upgrading window performance and durability.”
Window & Door Projects Completed Throughout the Greater St. Louis Area
Infinity Window Installation That Refreshed a Two-Story Home in Chesterfield, MO
Creating Space and Style with a New Sliding Door in Wildwood, MO
Elevating Curb Appeal with New Windows & Doors in Weldon Spring, MO
Window & Door Makeover Brought New Life to This Wentzville Farmhouse
Stunning Window Replacement for a Home in Lake Saint Louis, MO
Revamping a St. Louis Home with Custom Window Installation
Frequently Asked Questions about Window Replacement
What makes Replacement Windows by Lakeside a trusted St. Louis window contractor?
- We have been St. Louis’s exclusive Infinity by Marvin authorized contractor since 2006.
- We maintain a lifetime workmanship warranty in addition to the manufacturer’s warranty.
- Our installation is handled by factory-trained, in-house specialists, not subcontractors.
How far does your service area extend around St. Louis?
We serve the greater St. Louis metro area, including both eastern Missouri and parts of Illinois.
If your specific city isn’t listed, you can contact us — often we can still serve your area.
What warranties and guarantees come with my new windows?
- You receive a lifetime workmanship warranty from Lakeside in addition to the manufacturer’s warranty.
- Because we are an Infinity by Marvin authorized contractor, your installation meets their standards — guaranteeing the manufacturer warranty.
What factors influence the cost of replacing windows in St. Louis?
- Window size, configuration, and complexity
- The frame material and finish you choose (fiberglass vs vinyl or wood-like interior finishes) will impact price.
- Extra customizations like decorative hardware, grille patterns, and unique configurations add cost.
- Structural issues uncovered during installation (rot, damage) can require additional repair work. We always discuss with homeowners before proceeding.
Do you offer financing or special payment options for windows in St. Louis?
- Yes, we offer flexible financing plans through GreenSky
- We also have monthly special offers to help your project come to life
What is the window installation process when working with your team?
- We begin with precise measurements to ensure a custom fit.
- Our installers use polyurethane non-expanding foam (not expanding foam) for insulation, avoiding frame deformation.
- We seal each window with quality sealants to ensure air- and water-tightness.
- We finish with interior trim or reuse existing trim if it’s in good shape, then perform a final walkthrough.
For more details on our installation process, see our blog “What to During the Window Installation Process“
What styles and types of windows do you install in St. Louis homes?
We install Infinity by Marvin windows in a variety of styles; such as double hung, casement, and bow windows (to name a few).
Our windows are custom fit, and you can choose various operating styles, hardware, colors, finishes, and grille options.
When should I replace my windows rather than repair them?
- Signs like air leaks or drafts, condensation between panes, or difficulty opening/closing windows indicate it’s time.
- If your energy bills are steadily rising and windows are old or inefficient, replacement may give a better ROI.
- Older windows that are warping, rotting, or structurally unsound typically can’t be cost-effectively repaired.
See our “Replacement Window Guide” for in-depth information on when to replace your windows!
Why choose fiberglass (Infinity by Marvin) windows instead of vinyl or wood?
- The Ultrex® fiberglass used in Infinity windows is eight times stronger than vinyl and resists warping, bowing, and deterioration.
- Fiberglass has low thermal expansion (closer to glass), making seals more durable and less prone to failure.
- These windows are more energy efficient (Low-E coatings, argon gas fills) and offer long‑term performance with minimal maintenance.
Will replacing my windows lower my energy bills in St. Louis?
- Yes — poorly insulated or leaky windows allow heat transfer. Upgrading to energy-efficient windows can reduce heating/cooling costs.
- Our Infinity by Marvin windows come with Low-E coatings and argon fills, which help block heat gain/loss.
Make a Statement with Stylish Bay Windows Installed by Our Experienced Local Team
Your home is only a phone call away from the stunning multi-angle views, added architectural interest, and natural light that await you from Infinite by Marvin bay windows.
Schedule a free consultation to get started on dependable installation with Replacement Windows by Lakeside!
Special Offer
12 Months, No Interest/No Payments*
No interest until Fall of 2027!*
Don’t make a payment until Fall of 2027*
Executed contract date range: 9/1/26 – 9/30/26
