Everything You Need to Know About Fiberglass Windows

Maybe you’ve just bought a new home and don’t want to be stuck with the windows it came with. Or maybe you’re trying to put a new spin on your home’s facade. Wherever you are in your reno, you never expected there’d be so many decisions to make about your new windows! So how do you pick between vinyl and fiberglass windows?

fiberglass windows


What are Fiberglass Windows?

Fiberglass is a fiber-reinforced plastic. Its name is a bit deceptive: it’s made of compressed layers of woven, glass-derived fibers. It’s long been used to make surfboards and skis.

Many fiberglass windows are made of a wood-fiberglass composite, which boasts more strength than wood and vinyl. 

Do Fiberglass Windows Increase Curb Appeal?

One advantage of fiberglass is that it’s paintable. And you may find you have to paint it if you can’t find it in the color or finish you want. Some may like this DIY aspect, but others could find it a pain. Vinyl, on the other hand, comes in many colors that are inherent to its construction.

curb appeal with fiberglass windows

They won’t fade because the color is part of the deal. Since there’s more of a demand for vinyl, it’s offered in a wider variety of shades.

Many choose fiberglass windows because they resemble painted wood. But, unlike vinyl windows, their color actually fades from sunlight. And because the color is on the surface, it can show scratches so they’re not a huge improvement over genuine wood. 

Plus, if you’re trying to preserve the quirks of a historic house, fiberglass won’t approximate the look of the original. Something else consumers like about fiberglass windows is that the material is thinner, so they offer a lower profile. 

Beyond that, you can find fiberglass windows in all the same styles as vinyl. Open up your kitchen with casement windows, or transform your den with a sliding glass door (arguably the biggest window in your house). It’s just one more reason to pick vinyl over fiberglass – since they share so many features, you can get the same look at a better price point.

How Do They Compare Price Wise?

Vinyl windows are the clear winner when it comes to cost. They’re made by extruding PVC. If you’ve ever watched videos of 3D printing, it’s kind of like that. That means they’re easy to produce at scale and can be fabricated to custom fit your window opening. On average, a 48-inch vinyl windows costs between $520 and $730.

Fiberglass windows, on the other hand, cost between $572 and $1,693 per unit. They’re typically 10 to 30 percent more expensive but can cost up to 50 percent more. 

Is Fiberglass Practical?

The main thing fiberglass has going it is its toughness. Up to eight times stronger than vinyl, this material is known to be weather-resistant and high-performing. But let’s look more into just what that means.

“Strong” is a word we like to go with anything we choose for our house. But keep in mind that the window itself isn’t doing any heavy lifting. You want it to be able to stand up to the elements, but any strength beyond that won’t help you too much. 

That’s why you should really be looking at other measures of durability, like if it warps from hot and cold or degrades under UV light. Fiberglass has the advantage when it comes to warping – being so rigid, it doesn’t expand and contract from season to season. But fiberglass, unlike vinyl, weathers easily under sunlight. Plus, because it’s so rigid, it has lower tolerances. So there’s no room for mistakes during installation. 

Another practical issue is availability. We mentioned earlier that you don’t have your pick of options because this style isn’t as common. Fiberglass windows are in lower demand, so they’re not stocked as often as vinyl. That means you’ll have to wait longer for them to be manufactured and shipped. And as you know, home improvement projects can already test your patience.

The Bottom Line on Fiberglass Windows

Whether you get fiberglass windows will depend on your needs and preferences. How much are you willing to spend? How much time do you have? And what do you value most in a window? You also have to be okay with adding paint touch-ups to your chore schedule.

Fiberglass and vinyl check off the same boxes when it comes to choosing your new windows. Whatever you choose, you can never go wrong with choosing brand new windows that will increase your curb appeal and provide great energy efficiency.

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Window Resource started with one goal in mind - to help people become up-to-date on all things windows. Windows play a major role in your home's looks, value and energy efficiency so it's important to make the right decision when getting new ones installed. We'll cover just about every topic there is so you can make the best decision. Still don't see what you're looking for? Contact us and we'll answer any questions you may have.