If you’re replacing windows in Pittsburgh, you’re probably torn between vinyl and fiberglass—and you’ve likely heard conflicting opinions from every contractor in town. While both materials provide durability and energy efficiency, choosing the wrong one can lead to maintenance headaches or unnecessary costs. If you’re struggling to decide which type of window is best for your home, you’re not alone.
At Energy Swing, we’ve helped hundreds of homeowners make informed decisions about window replacements. With over 25 years of experience in the industry, we understand the real-world performance, costs, and long-term benefits of vinyl and fiberglass windows. Our goal is to give you an honest, side-by-side comparison so you can confidently choose the right fit for your needs and priorities.
This guide breaks down their key differences—durability, cost, and energy efficiency—so you can make an informed decision. By the end, you'll know exactly which type of window suits your budget, climate, and long-term goals.
What are Vinyl Windows?
Vinyl windows are made from PVC (polyvinyl chloride). This is a type of plastic known for its insulating value, durability, moisture resistance, and low maintenance needs.
Vinyl window frames are typically made up of multi-cavity hollows that are reinforced with aluminum for added durability and rigidity. While these air spaces provide insulation, they are sometimes filled with insulation to enhance energy efficiency. High quality vinyl windows have fusion-welded frames and sash corners for added strength.
Vinyl windows come in various styles and colors. They are designed to be energy-efficient by helping keep your home warm in the winter and cool in the summer. Since vinyl does not absorb moisture, they are also resistant to rotting, peeling, or rusting.
With Pittsburgh’s freeze-thaw cycles, vinyl is a popular choice for homeowners seeking an affordable, long-lasting option. Plus, there is little hassle of frequent upkeep. The material used for vinyl windows can expand and contract with temperature changes. Modern vinyl windows handle this fluctuation fairly well without compromising their performance.
What are Fiberglass Windows?
Photo credit: American Window Company
Fiberglass windows are made from glass fibers that are combined with resin. This creates a material that is incredibly strong, durable, and rigid.
Unlike vinyl, fiberglass windows use a material that can better withstand extreme temperatures and weather conditions. Fiberglass is known for its stability, so it doesn't expand or contract as much as vinyl. This makes it a popular choice for homeowners that live in extreme weather climates.
Fiberglass windows are often filled with insulating foam, which further boosts their energy efficiency, helping maintain consistent indoor temperatures and reduce heating and cooling costs.
Additionally, fiberglass frames are designed to be resistant to warping, cracking, and fading. In contrast, fiberglass cannot be welded which means the corners are joined mechanically or with adhesive, which is typically less durable than welded joints. This can result in a less aesthetically pleasing look.
Now that you’ve got the basics, let’s dive deeper and see how they compare in key categories.
Which Type of Window Is More Affordable?
- Vinyl Windows: Typically range from $300 to $1,500 per window, making them a cost-friendly option. Installation costs are generally lower due to the material's flexibility and ease of handling.
- Fiberglass Windows: Come at a higher price, averaging between $600 to $3,000 per window. The material's rigidity results in more expensive installation due to longer labor hours.
- 🏆 Winner: Vinyl
Which Windows Are More Energy Efficient?
- Vinyl Windows: Energy efficiency depends on the grade of vinyl selected. High-end vinyl offers strong insulation, especially when paired with quality glass.
- Fiberglass Windows: Typically 15% more energy-efficient than vinyl. Their rigid frame allows for tighter seals and better insulation properties.
🏆 Winner: Fiberglass. It’s almost a tie because it’s actually the glass that has the biggest impact on energy efficiency.
Which Windows Will Last Longer in Pittsburgh’s Weather?
- Vinyl Windows: Lifespan ranges from 25 to 50 years, depending on quality. Higher-end vinyl windows are designed with strength considered which makes them more resistant to warping and cracking.
- Fiberglass Windows: Boast a lifespan of 50+ years. They are highly resistant to warping, cracking, and fading, even in extreme weather.
- 🏆 Winner: Fiberglass
Which Windows Are Easier to Maintain?
Both fiberglass and vinyl are known for their easy maintenance. When it’s time for Spring cleaning after the cold Pittsburgh winter, all you need is warm soapy water and a rag to clean the frames.But there are a few differences when it comes to maintenance.
- Vinyl Windows: Vinyl windows require minimal maintenance and are very light, making cleaning the outside of the glass very easy. Since the color runs through the material, scratches are less visible.
- Fiberglass Windows: New fiberglass windows must be factory painted to protect the resin from UV exposure from the sun. In some cases when exposed to a lot of sunlight, the frames may need to be repainted over time if the exterior coating fades. Fiberglass is also heavier than vinyl so holding the sash to clean the outside might be more cumbersome.
- 🏆 Winner: Vinyl, but neither vinyl nor fiberglass require that much maintenance.
Which Windows Are More Customizable?
Style can be a deciding factor for many homeowners. If you live in a more modern neighborhood, like Cranberry, fiberglass windows could be a great option for their sleek, thin frames. In a more historical area like Mt. Lebanon, vinyl windows could be a better option for their flexibility in sizing.
- Vinyl Windows: Provide flexibility in design and custom sizing. Modern advancements offer heat-reflective coatings that allow for a broader range of color choices.
- Fiberglass Windows: Generally offer a thinner frame for a sleek look and a wider glass surface. Because the frames must be painted, fiberglass has traditionally been the leader in color options, but vinyl is quickly catching up.
- 🏆 Winner: Tie. Both have customization options that aren’t available to the other. If you want a wood-like finish, fiberglass offers a more realistic texture, while vinyl is ideal for custom shapes.
Which Type of Window Is Easier to Install?
- Vinyl Windows: Easier to install due to flexibility. Many installers are more familiar with vinyl, reducing labor time and cost.
- Fiberglass Windows: Require a more complex installation due to their rigidity, often necessitating a professional. Pittsburgh’s older homes often have custom window sizes or shapes, sometimes making fiberglass frames more challenging to install.
- 🏆 Winner: Vinyl
Which Windows Offer a Better ROI for Pittsburgh Homeowners?
It’s important to note that both materials qualify for the Energy Tax Credit when they are ENERGY STAR-certified windows. This can be a tax credit of up to $600 per year on new windows. Both windows also see a resale value return of 60-70% of the investment.
- Vinyl Windows: This is the preferred material in most replacement window projects. They have a lower initial investment cost with comparable energy efficiency, depending on the glass choice.
- Fiberglass Windows: While durable and long-lasting, their higher upfront cost may limit ROI. However, they offer greater long-term energy savings.
- 🏆 Winner: Vinyl
Your Next Step in Choosing the Best Windows
Now that you understand the key differences between vinyl and fiberglass, you're equipped to make an informed choice based on your priorities.
Choosing the wrong material could lead to costly maintenance and installation frustrations. When you weigh the pros and cons of each, you’re setting yourself up for a smart investment in your home’s future.
If you are most concerned with energy efficiency, but don’t want to spend as much on the product and installation, then vinyl windows are a great option for you. Or, if you’ve found your forever home and plan on living there for over 20 years, then fiberglass windows could be a great investment for your home.
Ready to explore your options? Get a free consultation with our window experts today. At Energy Swing Windows, we’ve helped homeowners for over 25 years find the right window solution. Contact us now to get a personalized recommendation.