Window & Door Replacement in Denver, CO
Gravina’s Window Center of Littleton® is Colorado’s original Infinity from Marvin replacement window expert—trusted by homeowners in Littleton, Denver, and across the Front Range since 1973. As a family-owned company with an A+ BBB rating, we specialize in high-performance Infinity fiberglass window installations, as well as patio doors, entry doors, and James Hardie® siding—each designed to handle Colorado’s climate and built to last. From decades of 5-star reviews to free in-home consultations, we make it easy to upgrade your home with products that deliver comfort, durability, and long-term value.
How We Make Window Replacement Easy
Step 1 – Let’s Talk Windows & Doors
Just give us a call or fill out our quick form to schedule your free in-home consultation. No pressure. No pushy sales tactics. Just honest advice from a local team who’s been doing this for 50+ years.
Step 2 – Get a Custom Plan & Quote
One of our friendly design consultants will come to your home, take measurements, and walk you through options tailored to your style, budget, and goals. You’ll get a clear, all-in-one quote—no surprises.
Step 3 – Sit Back While We Handle Everything
From expert installation to trim work, stain, and clean-up—we do it all. Our certified team installs your Infinity from Marvin fiberglass windows with precision and care, backed by our service and warranty.
Is It Time to Replace Your Windows in Colorado?
If you're dealing with drafty windows, higher energy bills, or outside noise creeping in, your home in Denver, Littleton, or anywhere along the Front Range may be overdue for an upgrade. Infinity fiberglass windows offer energy efficiency, strength, and peace of mind—engineered for Colorado’s climate.
At Gravina's Window Center of Littleton®, we specialize in full-frame installations that enhance both performance and design. Our proven 5-star process minimizes disruption, ensures expert craftsmanship, and delivers results that stand the test of time—no matter the age or style of your home.
Why Choose Fiberglass Window Replacement in Denver, CO?
Partner with Gravina’s Window Center of Littleton—Colorado’s most experienced Infinity from Marvin dealer, trusted by homeowners since 1973 for quality, integrity, and results that last.
- Installed by Marvin-certified experts for flawless performance
- Ultrex® fiberglass stands up to Colorado’s harsh temperature swings
- ENERGY STAR®-rated glass to help reduce your utility bills
- Clean, timeless design options that elevate your curb appeal
Whether you’re in Highlands Ranch, Arvada, or anywhere in between, we help Denver-area homeowners upgrade with confidence. Let us show you what window replacement done right really looks like.

INFINITY FIBERGLASS REPLACEMENT WINDOWS
Denver homeowners, are you in the market for Infinity replacement windows? If you're looking for reliable and trustworthy professionals to help you upgrade your windows and doors, look no further than Gravina's Window Center of Littleton®. Our team has decades of experience and stands at the forefront of educating homeowners in Colorado about window and door upgrades. We offer a range of services, from full-frame window replacement to insert installation, and our expert craftsmanship ensures that your unique needs are met. Let us help you enhance the beauty and energy efficiency of your home with our reliable expertise. We offer the best fiberglass windows on the market, Infinity from Marvin - Made from Ultrex fiberglass. With professional installation and a lifetime workmanship warranty, we do window replacement the right way.
MARVIN PATIO DOORS
As patio door experts, we offer our customers world-class choices for finding their perfect fit and style. With Marvin Infinity Windows, you get the highest quality patio doors on the market. Our collection of Infinity fiberglass sliding patio doors and Infinity french doors is purposefully designed to help make a home that's distinctively yours. Let us find a door solution just right for you.
INFINITY BIFOLD DOORS
When it comes to BiFold doors, we offer our customers the best choices from Infinity Windows. Our collection of Infinity fiberglass bifold doors are purposefully designed to help make a home that's distinctively yours. No matter your taste, energy efficiency needs, or desires, we will find you a door that's just right.
ENTRY DOORS
Ranked one of the top remodeling projects a homeowner can undertake regarding return on investment, selecting a front door is a fundamental part of designing your home's overall aesthetic. We carry ProVia and Therma Tru fiberglass entry doors. We have what you want. Learn more...
JAMES HARDIE SIDING
James Hardie invented fiber cement and remain committed to continually raising the bar for the rest of the industry. For decades, James Hardie has made the most beautiful, durable fiber cement products on the market.Ultrex® Fiberglass Windows: Built for Colorado’s Toughest Conditions
In Colorado, weather isn’t just a season—it’s a challenge. From scorching UV rays to heavy snow and hail, your home deserves replacement windows that can truly withstand the elements. That’s why Gravina’s Window Center of Littleton® proudly installs Infinity® from Marvin—engineered with Ultrex® fiberglass, the strongest window frame material on the market.
Ultrex is 8x stronger than vinyl, built to withstand Colorado’s extreme temperature swings without warping, cracking, or losing shape. Unlike typical vinyl windows, Ultrex expands 87% less with temperature changes—giving you a tighter, longer-lasting fit. Whether you live in Denver, Highlands Ranch, or up in Evergreen, Infinity windows deliver unbeatable durability, clean aesthetics, and energy-saving performance for decades to come.
Plus, with Low-E glass and argon gas fills, all Infinity from Marvin windows meet or exceed ENERGY STAR® requirements, helping to reduce your energy costs while increasing year-round comfort.
Don’t settle for vinyl—choose what’s truly built for life.
Why Homeowners in Colorado Prefer Infinity from Marvin
Infinity replacement windows aren’t just beautiful—they’re purpose-built for performance in Colorado’s rugged climate. Made with ultra-thin Ultrex fiberglass frames, these windows maximize natural light and deliver sleek, modern profiles that elevate any home design—from classic bungalows in Wash Park to custom homes in Castle Pines.
- More visible glass for better views and brighter interiors
- Long-lasting materials that outperform vinyl and wood alternatives
- Marvin’s trusted craftsmanship backed by decades of innovation
- Engineered for Colorado—resistant to expansion, contraction, and damage
With Gravina’s Window Center of Littleton®, you're getting more than just window replacement—you’re getting an award-winning local partner trusted by thousands of Colorado homeowners. Discover the Infinity advantage and invest in replacement windows that look better, perform longer, and are designed to handle anything the Rockies throw your way.
Our Promise Since 1973
At Gravina’s Window Center of Littleton®, family isn’t just part of the business—it is the business. As Colorado’s oldest authorized Infinity from Marvin® dealer, we’ve been helping homeowners in Littleton, Denver, and across the Front Range for over 50 years. Since 1973, three generations of the Gravina family have perfected the art of fiberglass window and door replacement, combining time-tested craftsmanship with cutting-edge performance.
Our mission is simple: to ensure every home we touch becomes more beautiful, energy efficient, and built to last. We don’t believe in shortcuts—only in doing what’s right for your home. That’s our legacy. That’s our promise. Because great homes deserve craftsmanship, not compromise.

Trusted by Colorado Homeowners Since 1973
Our reputation speaks for itself. See what real customers have to say about working with Gravina’s Window Center of Littleton®—from installation to results that last.
"I can’t say enough about how professional, fast, and clean the team was. Our Infinity windows look incredible!"
– Sarah M., Highlands Ranch
"We’ve done multiple projects with Gravina’s Window Center of Littleton. Always on time, respectful, and top-tier craftsmanship."
– David L., Denver
"From sales to install, everyone was knowledgeable and transparent. No high pressure, just great service from Gravina’s Window Center of Littleton."
– Lisa T., Littleton
Why Infinity from Marvin®?
From fiberglass window replacement to premium Infinity patio doors, choosing Infinity from Marvin is the smart, stress-free upgrade your Colorado home deserves. Our Infinity fiberglass replacement windows are engineered for strength, beauty, and long-term energy efficiency, offered in a wide range of sizes, shapes, and finishes to fit your home perfectly.
As the oldest Infinity from Marvin dealer in the country, Gravina’s Window Center of Littleton® provides exclusive access to Marvin’s full product line. Every Infinity window is built with Ultrex® fiberglass—a pultruded, patented material that’s 8x stronger than vinyl. That means superior energy savings, tighter seals, and unbeatable performance in Colorado’s ever-changing climate.
What Are Infinity Windows?
The Infinity Window is Marvin’s high-performance fiberglass line, designed to combine the classic look of wood with modern durability and low-maintenance finishes. Whether you're replacing old wood windows or upgrading from vinyl, Infinity offers unmatched strength, lasting beauty, and custom design options to fit any Denver home. All backed by the trusted service of Gravina’s Window Center of Littleton®.
*With approved credit. Not all applicants will qualify. Special offers are not valid for previous customer orders and cannot be combined with other discounts, offers, or estimates. Financing available to qualified homeowners based on creditworthiness and other criteria. Minimum purchase of (4) Infinity Windows required. Offer expires on 6/30/25. Financing terms, including 0% interest for up to 24 months, are estimates. Interest accrues from the date of purchase but is waived if paid in full within the promotional period. Actual rates and terms depend on credit approval and individual circumstances. See retailer for full terms and conditions. This is not a guaranteed offer. Inquiries regarding eligibility and financing options are encouraged.
Tired of drafty windows and renovation headaches? Choose Infinity from Marvin, Colorado’s smarter, stress-free way to replace windows and doors.
As Colorado’s oldest authorized Infinity from Marvin replacement window provider, Gravina’s Window Center of Littleton® delivers unmatched experience and lasting craftsmanship you can count on. Family-owned and A+ rated by the Better Business Bureau, we’ve been serving homeowners across the Denver Metro Area and the Front Range since 1973.
Our expert installation team specializes in full-frame replacement using durable, energy-efficient Infinity Ultrex® fiberglass windows and doors. From first consultation to final cleanup, we make the process seamless—improving your home’s comfort, appearance, and performance. Discover why generations of Colorado homeowners trust Gravina’s Window Center of Littleton® for replacement windows that are built for life.