Rosie on the House: The difference between vinyl and fiberglass windows | home and garden

Rosie Romero exclusive to the Arizona Daily Star

Question: I need to replace some windows. I can’t tell if I should use vinyl or fiberglass. What is the difference?

Answer: Replacing the windows in your home is not an easy decision, and choosing the materials for your window frame and scarves has a strong impact on the price you’ll pay and how long it will last.

Two of the most popular options are vinyl and fiberglass.

“We often find ourselves comparing the pros and cons of each, so that our customers have enough information to make a decision,” said Sal Soccato, owner of DunRite Windows & Doors, a Rosie certified partner. “But hands-free, replacing fiberglass windows is the best option for us.”

It’s not always the right choice for every homeowner, although there are key differences for each material that can determine which one is the best choice for your home.

Budget, window size and shape, and other factors such as how long a homeowner intends to stay in the home and how important color and appliances are to them can influence the decision.

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There’s a reason vinyl windows are the most popular choice in America. It is cost effective and can last more than 30 years, if it is a good quality window. They also come in a good selection of colors, options, and upgrades. It’s an economical option that can cost upwards of 20% to 30% less than fiberglass.

Why do they cost less? It is not only about the cost of raw materials, but also about the manufacturing process. more heavy-duty fiberglass windows; Thus, its manufacture costs more.

The corners use a hidden lock to hold the frame together which is held in by hand using glue and screws. This process and other aspects of fiberglass window manufacturing take time and labor. In contrast, vinyl is extruded with corners fusing (welded) together by a machine. It is a fast and easy to produce product.

However, you get what you pay for with a great window. A high-quality window will have a thinner frame and maximum glass, providing the most visibility and natural light. Additionally, you can have a wood grain texture over the fiberglass, which complements some homes beautifully, or you can choose a different color on the inside versus outside. This can really enhance your décor, especially if you choose an exterior black and white interior, which is currently one of the most popular color combinations.

Fiberglass is easy to paint, too, which is helpful if you decide to change the exterior colors of your home over time. Vinyl does not stick to paint and voids warranty. Repaint can be a choice or a necessity, depending on the product you’re buying. For example, Pella’s Impervia line of fiberglass windows features a strong finish that Pella claims never needs painting or refinishing…something every homeowner is sure to appreciate.


“If the homeowner intends to stay in their home for an extended period of time, fiberglass is the best option,” Sokato says. “It can last for 50+ years, compared to the 20-30 years you’d get from a high-quality window vinyl.”

If you’re the type of homeowner who rarely stays in the house for more than a decade, Sokato recommends not spending the extra money on fiberglass unless you prefer the look. Expect that you will not recoup the investment before you leave.

However, if your home is forever or a home you hope to pass on to your children, it may be worth taking a closer look.

Energy Efficiency

While vinyl windows are more energy efficient than aluminum windows, fiberglass windows outperform them. Fiberglass is made of a finely spun fiberglass mat blended with polyester resin, as opposed to a vinyl window made of PVC (polyvinyl chloride).

It is less likely to retain or transfer heat through the tire into the home. According to The Spruce, they are rated 15% higher than vinyl windows, when it comes to an R-value, which is how well a window slows down the rate of heat transfer.

Fiberglass frames can be hollow or insulated, which affects the overall energy efficiency of the window, along with other features such as the number of low-emissivity glass coatings, the gas filling between the panes of glass, and the number of panes of glass in the window.


Not only do fewer manufacturers create fiberglass windows, compared to the plethora of vinyl options available, but it can also be very difficult to order fiberglass in special shapes – although the Pella Reserve product line has a window shape. arched;

Fiberglass is also more expensive than the same specialized form vinyl replacement window. This is often the reason why some homeowners choose vinyl over fiberglass windows, or why they choose to install a different brand and/or window material for this niche shape, but not others.

“I’ll say this about specialized shaped fiberglass windows; when you find the perfect size at the right price, a fiberglass specialist window is much stronger than a comparable vinyl window. Their structural strength is impressive. You’ll also appreciate that it has a thinner vinyl frame,” Sokato says. “This could be something to think about.”

weather changes

Vinyl and fiberglass windows are weatherproof, so the frame itself won’t have moisture issues due to rain or dampness. They will also not rot, rust, warp, or explode from heat.

However, fiberglass has one advantage over vinyl when it comes to the weather: it doesn’t stretch in hot summers or shrink during cold winters. All other window materials do this, which can lead to gaps and air leaks, or the chances of moisture and insects getting into the walls around the window opening. Even if the weather changes are severe, fiberglass is impervious.

Fiberglass is basically the same material as sheet glass, so they compliment each other in any slight changes that occur.

This lack of thermal movement is the main reason behind the longevity of the fiberglass window. Vinyl windows lose their flexibility over time, become brittle, and damage them when the window widens or retracts. Fiberglass that is 30, 40, or even 50 years old is as strong as the day it was installed.

“Because fiberglass windows are rigid, their installation is less forgiving than vinyl windows, which have some flexibility in them,” Sokato says. “So, it’s important that they’re installed correctly. It’s just one reason DunRite offers a lifetime installation guarantee as long as the buyer owns the home. We stand behind our quality workmanship, so you know it’s a job done right.”


When it comes to the amount of effort required by a homeowner to maintain windows, vinyl versus fiberglass comes in fairly equal measure.

Other than replacing caulk or sealant when necessary, keeping the glass clean and opening weeping holes (which Sucato recommends doing before summer arrives), there’s very little maintenance to be done.

Both have finishes that last the life of the window, although some fiberglass or vinyl windows may need occasional repainting, depending on whether or not it’s factory paint, and the life expectancy of the paint.

informed decision

Be sure to discuss all of your options.

No matter which direction you’re leaning, it’s important to discuss your exact budget, preferred styles, colors, and other options with the salesperson while getting price estimates for your replacement windows.

They can help you make an informed and appropriate decision for your home. Just remember that a seller who sells only one brand or product line can recommend what they sell, so if you’re considering fiberglass windows, Sucato encourages you to make sure they sell fiberglass products, as well as vinyl. They will have the experience and knowledge of the product to discuss the pros and cons.

Special Note: Rosie listeners and/or readers have long heard in the House of Representatives my concerns about vinyl windows and doors. My feelings go back to being years ago when the first generations of vinyl products justified my concern. Today, recent technological improvements from some manufacturers along with the correct installation experience can make it a viable option.

Rosie Romero, an expert in the home building and remodeling industry in Arizona since 1988, is the host of Rosie’s Saturday Morning House radio broadcast, which is heard locally from 10-11 a.m. on KNST (790 a.m.) in Tucson and 8 a.m. 11 a.m. on KGVY (1080-AM) and (100.7-FM) in Green Valley.

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