Fiberglass Windows vs. Vinyl Windows – Which Material is Best?

We field questions every day on which material – wood, vinyl or fiberglass – is best and why. We’ll focus this discussion on vinyl and fiberglass materials. Fiberglass has been around for decades, but recently, it has achieved more attention due to its superior strength, weatherability, energy efficiency and low maintenance requirements. Fiberglass windows are taking a big slice out of the more expensive vinyl window markets and leaving many vinyl window manufacturers fighting for the low-quality, budget window market. Find out why fiberglass – and specifically, Ultrex pultruded fiberglass – is becoming the smart choice over vinyl for more and more homeowners.

As a smart homeowner, you want to…

Choose a material that is both tough and smart.

Our Integrity windows by Marvin are made from Ultrex pultruded fiberglass — it’s tough, durable and built to last. It’s eight times stronger than vinyl and three times stronger than vinyl/wood composites. Windows from Integrity perform at the highest level for the full duration of their life. And they live a long, happy life (as much as 38% longer than vinyl1)—making them an incredibly smart investment.

  • Ultrex fiberglass is more than 8X stronger than vinyl.
  • Fiberglass is a green building material and requires 39% less energy to produce than vinyl.
  • Vinyl windows are not particularly strong or rigid and have a tendency to sag due to their flexibility.
  • Vinyl window frames can soften, warp, twist and bow when heat builds up within the frame.
  • Fiberglass is the fastest growing window and door material in the industry.

Create a comfortable home

Windows keep your house cool in the summer and warm in the winter. Integrity’s dual-paned, insulated glass windows with LoE II coating absorb heat in the winter and reflect it in the summer, also reducing damaging UV rays. Additionally, our tri-pane windows with argon gas achieve U-Factors as low as .18, making your home a comfortable oasis in even the harshest environments. Many Integrity products exceed Energy Star guidelines and qualify to be part of an elite “Most Efficient Program” established by the federal government.2

  • Ultrex fiberglass expands and contracts at nearly the same rate as glass to prevent seal failures (the appearance of condensation BETWEEN the glass panes which indicates the glass has lost its insulating effectiveness).
  • Vinyl expands and contracts at a rate of 8X more than glass leading to potential seal failures, frame failures and air gaps.

Get the most for your money

The total value you receive with Integrity Windows is a huge advantage. Multiple factors provide value that’s impossible to ignore:

  • Energy Savings: Integrity’s Energy Star® qualified windows can save you 15% on your total energy bill.³
  • The Warranty: A full 20 years on glass seals and 10 years on manufacturing defects.
  • U-Factor: Our windows with triple-pane glazing boast U-Factors as low as .18.
  • Life Expectancy: A recent study reported that fiberglass windows have a 38% longer useful life expectancy than vinyl.1
  • Ultrex fiberglass has a 38% longer useful life expectancy than vinyl.1
  • Ultrex fiberglass is price competitive to high quality vinyl windows.
  • Ultrex fiberglass resists UV degradation (chalking, fading and cracking) 5X longer than vinyl.

Enhance the look of your home

Integrity Windows are Built to Perform® — for a long, long time. So, unlike most of your design choices and furnishings, they are long-term fixtures in your home. Integrity Windows are available in both classic and modern styles to reflect your style with lasting quality. A variety of available exterior colors allow for an understated look or an adventurous accent mark. Exterior trim and divided lites can add a beautiful touch, and with the durability of Ultrex you’ll have plenty of time to admire them instead of maintaining them.

  • Fiberglass windows can be built with thinner, stronger frames than vinyl or composites like Fibrex, allowing larger openings and more daylight.
  • Ultrex provides a superior, consistent finish that can be painted, even in dark colors, without voiding the warranty.
  • Ultrex is the only product in the fiberglass, vinyl or composite category whose finish is certified for quality and durability by the American Architectural Manufacturers Association (AAMA).4
  • Integrity windows are available in Wood/Ultrex – beauty of wood interior and durability of Ultrex fiberglass exterior.

Fiberglass Windows vs. Vinyl Windows – The Bottom Line…

More architects, contractors and homeowners are choosing durable, beautiful fiberglass windows, making fiberglass the fastest-growing material in the window and door market. And Ultrex has a longer track record than any other fiberglass product on the market. We spent a considerable amount of time researching the best window manufacturers and made visits to several manufacturing facilities to see how the windows are constructed. We’re confident that Integrity Windows by Marvin are a better value than vinyl windows and competitive fiberglass or composite windows.

Stop by our Idea Showroom and let us show you the comparison between vinyl and fiberglass windows. Or, we can come to your home for a No Obligation Consultation. Call us today to set up your appointment and see the difference for yourself.

1 – Life cycle assessment of windows for the North American residential market. Case study by the University of British Columbia. Scandinavian Journal of Forest Research, 2008.
2 – http://www.energystar.gov/index.cfm?c=partners.most_efficient_criteria
3 – http://www.energystar.gov/index.cfm?fuseaction=find_a_product.showProductGroup&pgw_code=WI
4 – The Ultrex patented coating system is AAMA 623-10 certified and is listed on the exclusive AAMA Verified Components List for 624-10 and 625-10.