Infinity from Marvin Blog
Everwood Fiberglass windows
08 NOVEMBER 2022

Fiberglass vs Wood Windows: What’s the Difference?

One of the most important decisions when replacing your home’s windows is choosing the right material. As we touched on in the Vinyl vs Fiberglass blog article, this can seem overwhelming simply due to the number of options available. Here, we’ll discuss two of the more popular options, fiberglass and wood, so you can feel confident making the best decision for your home.

Wood windows

Wood has been a popular window material option for centuries due to its abundant supply and the traditional detail it offers. Compared to materials like vinyl, wood is a strong, durable option that resists warping during temperature changes.

Originally made by craftsmen, wood windows were built with an artisan’s touch. Modern wood windows continue to convey a sense of craftsmanship and detail, and are often selected for their rich, traditional appeal. Wood windows also can add charm and beauty to a home.

However, upholding that charm and beauty long-term requires periodic care and preservation. While wood windows offer strength and stability, they tend to require more maintenance and refinishing. Inspecting, sanding, reapplying stain, resealing, and repainting, are all part of owning wood windows. That’s a lot of work.

Wood windows also tend to cost more than other materials, especially when you factor in the cost of maintenance, repair, and eventually, replacement (again).

Is there a way to have the traditional look and character of wood, but more durable and with less maintenance?

Fiberglass windows

Compared to other materials, fiberglass is the strongest material you’ll find for replacement windows. Since fiberglass windows don’t deteriorate or rot, they offer better strength and stability than wood windows, and without the maintenance. Due to the resiliency of the material, fiberglass maintains its shape even in the harshest of climates with regular exposure to temperature variation, wind, rain, or snow. Fiberglass windows expand at virtually the same rate as glass, making them more resistant to leaks and seal failures that can affect long-term performance.

Infinity from Marvin’s Ultrex® fiberglass 

While fiberglass is a superior material compared to wood, not all fiberglass windows and doors are the same. Infinity from Marvin’s Ultrex fiberglass is a proprietary composite designed and engineered by Marvin — making our windows truly unique. In fact, when it comes to strength, stability, and durability, Ultrex fiberglass continues to outlast and outperform the competition.

Ultrex fiberglass is 8x stronger than vinyl and 3x stronger than wood/vinyl composites — supporting up to 34,000 pounds. That strength allows for narrower frames, bigger views, and additional sunlight in your home

Ultrex fiberglass is thermally stable, so it expands 87% less than vinyl windows. That stability means Infinity from Marvin’s windows and doors stay tight and true even after extreme temperature swings. By expanding and contracting at nearly the same rate as glass, Infinity windows made with Ultrex are more resistant to leaks and seal failures so you can enjoy your windows for years to come.

The strength of fiberglass windows is important, but Ultrex fiberglass has more than strength — it adds beauty. Infinity's proprietary acrylic finish is 3x thicker and smoother than the competition. The finish resists scratching and denting and performs so well that Infinity offers dark colors without fear of UV degradation or fading.

EverWood vs Wood grain comparison on windows


So fiberglass is strong, but what if you want the look, warmth, and character of wood? With Infinity’s EverWood interior finish, you will enjoy the natural appearance of wood, without the maintenance and refinishing. EverWood is an Infinity-exclusive wood grain interior finish engineered to deliver everything you love about wood windows. EverWood looks and feels like real wood and can be stained to match your existing woodwork. Designed and engineered by the wood window experts at Marvin, Infinity’s EverWood interior finish has the traditional details, profiles, and designs other replacement windows can’t match. And EverWood is made from an inorganic material, so it won't absorb moisture or decay over time. You’ll enjoy remarkable performance and long-lasting beauty.

EverWood color samples

Infinity from Marvin has it all

Wood windows are full of character and beauty, but you truly can have it all with Ultrex fiberglass. At Infinity from Marvin, we believe replacing your windows is a decision you should only have to make once, which is why we make the best windows from the best material. We created Ultrex fiberglass windows so you can enjoy the strength, performance, and beauty your home deserves.

Ready to get your fiberglass window replacement project started? Schedule your free no-obligation consultation with a local expert.


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