Compare Fiberglass vs. Vinyl Windows

By Jessica Wimmer Updated February 2, 2024

Get Estimate

Enter details in under 3 minutes

All products and services featured are independently selected by our editors. However, when you buy something through our retail links, we may earn an affiliate commission.

Fiberglass and vinyl are two of the most popular window frame materials. They each have different selling points, with one being more cost-effective and the other more energy-efficient and eco-friendly. We compared the pros and cons of each material to help you decide which may be better for your home. You can also read our guide to the best replacement window companies to find an installer that can advise you.


Fiberglass Windows: Overview

Fiberglass is made from glass that’s melted under high heat and then pulled into fine glass fibers that are woven together. When used for solid construction like window framing, it’s mixed with resins that allow it to be molded into shape. Fiberglass is paintable, smooth, and can be textured to look like wood. It’s also slightly thinner than vinyl, so many homeowners think it looks more attractive.

Fiberglass window frames have practical benefits, too. Fiberglass is highly durable and requires little maintenance. It’s stronger and more warp-resistant than vinyl. A fiberglass window can look great 50 years after installation, whereas a vinyl one will last around 30 years. 

Fiberglass also does a better job of controlling temperature loss, making it more energy-efficient. Its glass base gives it better insulation than vinyl, which is valuable if you live in a noisy area.

Additionally, fiberglass is more environmentally friendly than vinyl. It’s made from recycled glass, and its manufacturing process doesn’t release harmful chemicals into the environment, nor does it release harmful byproducts if there’s ever a fire in your home. 

The main drawback of fiberglass windows is that they’re more expensive than vinyl. Though still more cost-effective than wooden windows, fiberglass costs 10% to 30% more than vinyl on average. You’ll also have to pay a contractor to install these windows, as it’s not an easy do-it-yourself (DIY) job.

The installation process is more time-consuming as well. Whereas vinyl windows come in standard sizes you can easily buy at a home improvement store, fiberglass windows must be purchased from a manufacturer, many of which will void your warranty if you don’t get the windows installed by a professional.


Benefits and Drawbacks

UpsidesDownsides

More attractive and customizable

More expensive than vinyl

More durable and long-lasting

Requires professional installation

More energy-efficient, eco-friendly, and sound-absorbing

Can’t be purchased at a home improvement store


Vinyl Windows: Overview

Vinyl windows are much more affordable than fiberglass. They’re actually made from a kind of plastic. Its technical name is polyvinyl chloride (PVC). Plastic is much safer to work with than fiberglass, since there are no glass fibers to inhale. You may be able to install vinyl windows yourself and save $100 to $200 per window, though we always recommend hiring a pro.

Vinyl is just as low-maintenance as fiberglass. You can easily wipe away any dirt, dust, or spills to keep vinyl looking great for decades.

The downside of vinyl is that it expands in extreme temperatures, so it’s more prone to warping and cracking in hot climates. It’s also not as eco-friendly as fiberglass. It’s difficult to recycle, and its production emits harmful chemicals. If there’s a fire in your home, vinyl will melt and release harmful chemicals into the air. Vinyl is also not as energy-efficient as vinyl, and it won’t do as much to block sound.


Benefits and Drawbacks

UpsidesDownsides

More cost-effective than fiberglass

Not as long-lasting as fiberglass

Possible to install yourself

Less energy-efficient and eco-friendly

Low-maintenance

Harder to customize and make look attractive


Fiberglass vs. Vinyl: Cost

Both fiberglass and vinyl are less expensive than wood, but you’ll save more money by opting for vinyl. Vinyl windows cost roughly $500 to $950 per window, including professional installation, whereas fiberglass windows cost $600 to $1,100 with installation.* That may not make much of a difference if you’re installing one or two new windows, but you’ll save considerable money if you’re doing a big window replacement project.

That being said, fiberglass windows have a higher resale value. Because they’re more energy-efficient, the money you save on energy bills may also balance out their initial cost.

*Cost figures via Fixr.com.


Fiberglass vs. Vinyl: Installation

Vinyl windows are easier to install. The material is far more flexible than fiberglass, making it easier to work with and fit into a window opening. You can install these windows yourself, waiving the cost of professional installation, but you’ll still save money if you hire a contractor to do the job. Vinyl window frames are roughly $50 less expensive per window than fiberglass. 

Get Estimates From Local Window Installers Near You
Just answer a few questions, and we’ll take care of the rest!

Comparison Table

Compare fiberglass and vinyl on key variables in the table below.

Comparison FactorFiberglassVinyl

Appearance

More attractive

Less attractive

Cost

$600–$1,100

$500–$950

Durability

More durable

Less durable

Energy efficiency

More energy-efficient

Less energy-efficient

Eco-friendliness

More eco-friendly

Less eco-friendly

Installation

Requires professional installation

Can be DIY

Life span

50 years

30 years

Maintenance

Low-maintenance

Low-maintenance


DIY vs. Professional Installation

Unless you’re handy around the house, we recommend professional window installation for both vinyl and fiberglass windows. Fiberglass always requires professional installation, not only because it’s more difficult to work with but also because you may void your manufacturing warranty if you try to install it yourself and damage the material.

You may be able to install vinyl windows yourself if you’re experienced at home improvement projects, but we recommend hiring a pro for the best-looking outcome, as this is a project with very visible results.


Our Recommendation

Both fiberglass and vinyl are high-quality window options and popular choices for homeowners. The best window material depends on your priorities. Fiberglass looks better and lasts longer, but vinyl windows are more cost-effective. Either option is less expensive than traditional wood windows, but each has its own drawbacks.


Fiberglass vs. Vinyl Windows FAQ

Are vinyl or fiberglass windows better?

Whether vinyl or fiberglass is better depends on your priorities. Fiberglass windows are more durable, energy-efficient, and attractive than vinyl windows. Vinyl is more cost-effective and easy to install. 

What are the disadvantages of fiberglass windows?

Fiberglass windows are more expensive than vinyl. They also require professional installation and aren’t easy to find in home improvement stores, so you’ll need to order them from a manufacturer.

What are the downsides of vinyl windows?

Vinyl windows typically don’t last as long as fiberglass. They’re more vulnerable to cracking and warping and are less sound-resistant, energy-efficient, and eco-friendly. 

Are fiberglass windows worth it?

Fiberglass windows are durable, long-lasting, and energy-efficient. Though they’re more expensive up-front than vinyl windows, you may come out financially equal or even better with fiberglass windows.


How We Chose the Top Window Brands

We researched and analyzed dozens of window manufacturers. We then crafted a rating system based on each brand’s standard and energy-efficient product offerings.

We spoke directly to representatives at each company to learn how the installation process works and determine how each brand personalizes its windows for each home. We also closely analyzed each company’s warranty options to ensure their product and labor guarantees match or exceed industry standards. 

Finally, we assessed the manufacturer’s years of experience and customer reputation. In addition, we analyzed the 100 most recent Google Reviews for each provider across various locations and branches.