Pros and Cons of Fiberglass Windows – The Truth about Fiberglass Windows

Choosing the right windows for your home is a big decision. Among the many options, fiberglass windows have gained popularity for their durability and sleek design. In this article, we’ll explore the ins and outs of fiberglass windows, comparing them with other common choices like vinyl and wood. Our goal is to provide you with a clear picture of what fiberglass windows offer, helping you make an informed choice for your home.

fiberglass arizona windows interior of home

Understanding Fiberglass Windows

Fiberglass is a strong, lightweight material made from fine glass fibers. It’s known for its toughness and flexibility, qualities that are particularly beneficial in window manufacturing. Fiberglass windows are created through a process called pultrusion, where the glass fibers are pulled through a resin, forming a durable, weather-resistant composite material.

One of the standout features of fiberglass windows is their strength. They are less likely to warp, swell, or shrink under extreme temperatures, making them a reliable choice for any climate. This resilience also means they can hold large panes of glass, ideal for homeowners looking for expansive views with minimal obstructions.

Fiberglass windows are not only strong but also energy-efficient. Their frames can be filled with insulation, making them excellent at keeping your home warm in the winter and cool in the summer. This can lead to significant energy savings over time, a benefit that’s both environmentally friendly and kind to your wallet.

Aesthetically, fiberglass windows have a lot to offer. They can be manufactured in a variety of colors and finishes, mimicking the look of painted wood without the need for regular maintenance. Whether your home is modern or traditional, fiberglass windows can be designed to complement its style.

In summary, understanding the makeup and benefits of fiberglass windows is the first step in determining if they’re the right fit for your home. Their durability, energy efficiency, and aesthetic flexibility make them a strong contender in the window market.

Pros of Fiberglass Windows

Durability and Longevity: One of the biggest advantages of fiberglass windows is their durability. Unlike other materials, fiberglass resists the wear and tear from weather and time. It doesn’t warp, swell, or shrink, which means it can last for many years without losing its shape or functionality. This makes fiberglass windows a great long-term investment for your home.

Energy Efficiency

Fiberglass windows excel in energy efficiency. Their frames can be filled with insulation, stopping cold air from entering your home in the winter and keeping cool air inside during the summer. This insulation capability can lead to significant savings on your energy bills, making fiberglass windows an eco-friendly choice for your home.

Low Maintenance

If you’re looking for windows that require little upkeep, fiberglass is an excellent choice. Unlike wood, which may need regular painting or staining to prevent weather damage, fiberglass windows maintain their appearance without much effort. This low maintenance requirement can save you time and money in the long run.


Fiberglass windows offer a range of aesthetic options. They come in various colors and finishes, some of which mimic the natural look of wood. This versatility means you can achieve the perfect look for your home, whether it’s contemporary or traditional, without compromising on durability or efficiency.

Cons of Fiberglass Windows

Cost: While fiberglass windows offer many benefits, they can also be more expensive upfront than their vinyl or some wood counterparts. This initial investment is something to consider, although it’s worth noting that the durability and energy savings can offset the cost over time. Fortunately, vinyl windows are a more cost effective option if budget is a main factor. Check out our guide on vinyl windows here!

Limited Availability

Fiberglass windows are not as widely available as vinyl or wood windows. This limited availability can make it harder to find specific styles or custom options, potentially limiting your design choices.

Professional Installation is Necessary

Installing fiberglass windows requires precision and expertise to ensure they perform as intended. This means you’ll likely need to hire professionals for the installation, which can add to the overall cost. However, proper installation is crucial for maximizing the benefits of fiberglass windows, including their energy efficiency and longevity.

Understanding these pros and cons can help you decide if fiberglass windows are the right choice for your home. They offer a mix of durability, efficiency, and aesthetic flexibility, with considerations around cost and installation to keep in mind.

Comparing Fiberglass, Vinyl, and Wood Windows

When it comes to selecting windows for your home, it’s helpful to compare your options. Fiberglass, vinyl, and wood windows each have unique benefits and drawbacks. Here’s a breakdown to help you understand how they stack up against each other:


 Vinyl windows are generally the most affordable, followed by wood and then fiberglass. While the initial cost of fiberglass windows is higher, their longevity and energy efficiency can provide cost savings in the long run.


 Vinyl and fiberglass windows are both low maintenance, requiring only occasional cleaning to keep them looking new. Wood windows, on the other hand, need regular treatment to prevent weather damage and decay.


 Fiberglass windows are extremely durable, resistant to warping, swelling, and shrinking. Vinyl is also durable but can be more susceptible to extreme temperatures. Wood offers natural beauty but can deteriorate faster if not properly maintained. For additional info and help check out this video.

Energy Efficiency

 Fiberglass windows offer superior energy efficiency due to their ability to be filled with insulation. Wood windows also provide good insulation but can be less efficient over time as they age. Vinyl windows offer good thermal resistance, but the material’s expansion and contraction can affect their efficiency.

Aesthetic and Design Flexibility

 Wood windows offer a classic, natural look that many homeowners love but may require more upkeep. Fiberglass windows can mimic the look of wood and can be painted, offering a blend of beauty and practicality. Vinyl windows come in various colors and styles but cannot be painted, limiting customization options.

The Importance of Professional Installation

Regardless of the type of windows you choose, professional installation is crucial. This is especially true for fiberglass windows, where the precision of installation impacts their performance, efficiency, and lifespan. Here’s why expert installation matters:

Ensuring Proper Fit

 A professional installer can ensure that your fiberglass windows are correctly measured and fit snugly in your home, preventing air leaks and energy loss.

Maximizing Performance: Proper installation ensures that your windows operate smoothly, opening and closing easily without straining the frames or hardware.

Maintaining Warranty: Many window manufacturers require professional installation as a condition of their warranty. An expert installation ensures that your investment is protected.


 Incorrectly installed windows can be a safety hazard. Professional installers have the training and experience to install windows safely and securely.

Utah Window Experts understands the significance of professional installation. Our team of skilled installers ensures that your fiberglass windows are installed to the highest standards, maximizing your home’s comfort, efficiency, and beauty.


Choosing the right windows for your home involves weighing the pros and cons of materials like fiberglass, vinyl, and wood. Fiberglass windows, with their durability, energy efficiency, low maintenance, and aesthetic appeal, offer a compelling option for many homeowners. While the initial cost and necessity for professional installation may seem like drawbacks, the long-term benefits and savings often justify the investment.

As you consider the best window material for your home, remember that the right choice depends on your specific needs, preferences, and the climate where you live. Fiberglass windows stand out for their ability to withstand harsh weather conditions, maintain energy efficiency, and complement any home design. However, the decision should align with your budget, maintenance willingness, and the overall look you desire for your home.

For those in Utah considering new or replacement windows, Utah Window Experts is here to provide guidance, expertise, and professional installation services. We understand the importance of not only choosing the right windows but also ensuring they are installed correctly to maximize their benefits.

FAQs or Additional Resources

Q: What is the downside of fiberglass windows?

A: Fiberglass windows are known for their strength and durability, but they do come with a few downsides. Firstly, they can be more expensive than other types of windows, such as vinyl. This initial investment might not fit everyone’s budget. Secondly, while they come in various finishes and colors, the options might be more limited compared to vinyl or wood, potentially making it harder to match your home’s aesthetic. Lastly, though they are durable, if they do get damaged, repairs can be more challenging and costly compared to other materials.

Q: Are fiberglass windows worth it?

A: Whether fiberglass windows are worth it depends on your specific needs and budget. They offer excellent insulation, which can lead to energy savings over time, potentially offsetting their higher initial cost. Their durability means they can last longer than many other types of windows, reducing the need for replacements. If you’re looking for a long-term investment in your home’s efficiency and aesthetic, fiberglass windows can be a great choice. However, if you’re restricted by budget or prefer a wider variety of design options, other materials might be more suitable.

Q: What is the life expectancy of fiberglass windows?

A: Fiberglass windows are among the most durable options on the market, with a life expectancy that can exceed 50 years. This longevity is due to fiberglass’s resistance to warping, rotting, and corrosion. It also doesn’t expand or contract significantly with temperature changes, which helps maintain its integrity over time. Proper installation and minimal maintenance can ensure that fiberglass windows last for decades, making them a cost-effective option in the long run.

Q: Are fiberglass windows good in cold weather?

A: Yes, fiberglass windows perform exceptionally well in cold weather. They offer superior insulation compared to other materials, helping to keep your home warm and reduce energy costs during the winter months. Fiberglass does not conduct cold as much as aluminum, and its low thermal expansion rate means it maintains its seal and efficiency even in extreme temperatures. This makes fiberglass windows an excellent choice for homes in colder climates, ensuring comfort and energy efficiency year-round.

For those interested in exploring more about fiberglass windows or needing assistance in selecting the right windows for their home, Utah Window Experts is ready to help. Visit our website for more information, resources, and to schedule a consultation with our team of window professionals.