Pioneers in Fiberglass Window Replacement

We are Denver's oldest dealer of Infinity from Marvin Replacement Windows and Exterior Doors. Offering Service for Residents of Denver, CO & All Surrounding Areas


If you’re in the Denver, CO area and need replacement windows, we can help. From replacing full frame windows to insert window installation, Gravina’s has you covered.  We offer the best fiberglass windows on the market, Infinity from Marvin.  With professional installation and a lifetime workmanship warranty, we do windows the right way.

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 When it comes to patio doors, we offer our customers the best choices. Our collection of sliding patio and french doors is 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.

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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 have what you want.

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As one of the original INFINITY FROM MARVIN window dealers in the country, we know all about the strength of fiberglass.  Fiberglass has an astounding strength-to-weight ratio, which is one of the reasons why it’s the material of choice for boats, bridges, guardrails, ladders, and hard hats.  Imagine a ladder or a bridge made from vinyl!  Now think of vinyl windows and what happens to them in Colorado's altitude and solar exposure.

Fiberglass is highly durable, won’t leak or corrode, resists rot and doesn’t expand and contract in Denver’s extreme temperature swings. These properties make INFINITY from Marvin’s Ultrex fiberglass 800% stronger than vinyl and a far more durable material. Vinyl replacement windows can't stand up to Colorado's UV and temperature swings, meaning they are only a short-term solution for your home.

How does all of this come together for window replacement?  Infinity from Marvin fiberglass windows expands at the same rate as glass, which means our replacement windows stay tight and make them impervious to leaks, seal failures and stress cracks that can compromise energy efficiency and long-term performance.  Vinyl windows are plastic.  You might save a little on vinyl windows at first, but for total value and durability, INFINITY from Marvin's patented ULTREX fiberglass is the smart way to replace your windows.  Plastic is cheap...think FIBERGLASS!

A family tradition since 1973.

Gravina's Window Center of Littleton is a Family Owned and Operated Window Replacement Company for Over 44 Years, Built on Family Values.

mark schlereth and gravinas window center

Proudly endorsed by Mark Schlereth







Front Doors, Patio Doors & Storm Doors Professionally Installed for Homeowners in Denver, CO & Neighboring Communities

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