Fiberglass Window Replacements | Fiberglass Windows Replacement Frames
Fiberglass windows are fairly new to the market. They are made with some post consumer glass recycled into what are called "pultrusions" This is similar to extrusions, but is pulled through the die instead of being pushed through the dies. High cost and low availability have made this product rare in the marketplace. It has some advantages such as strength and it is paintable. It is used in less than 1% of windows today.
The Advantages of Fiberglass Windows
Fiberglass Windows - Fiberglass windows are one of the newer window choices, and a viable 'green' alternative for those concerned with the offgassing involved with vinyl. Fiberglass windows are made with post-consumer recycled glass (about 60%) and are durable, long-lasting, paintable, and very strong. They won't rot, warp, shrink, sag, or become brittle.
Features - As with other window frame options, fiberglass windows offer consumers maximum customizability. Homeowners can get fiberglass windows in just about any shape, style, and size and with any combination of gas fills, low-E coatings, grids, and so on. Hardware and window accessories also offer a broad range of stylish, convenient, and safety-oriented choices.
Energy Ffficiency - A fiberglass frame is just as efficient as a vinyl frame. However, fiberglass windows are typically built with metal spacers with rubber gaskets. These types of spacers are less energy efficient than the no- metal "super spacers" generally used with vinyl windows. In the big picture, though, super spacers are less effective at combating heat transfer than gas fills and low-E coatings, and they are a more expensive feature as well. For most budget-oriented consumers, that makes fiberglass windows just as efficient as vinyl windows.
Cost - Fiberglass windows are very strong, and very durable. As a result, they are usually priced higher than vinyl windows. The cost of fiberglass windows can vary considerably, depending on the manufacturer, so some comparison shopping is recommended. Though more expensive than vinyl, fiberglass windows are still considered a mid- priced window.
Fiberglass windows offer homeowners many more options than most vinyl windows. Fiberglass windows can be painted, which means endless color choices. However, with more flexibility comes more responsibility. Homeowners who choose fiberglass windows may end up repainting their windows out of necessity rather than choice, as paint colors fade and weather over time. The fiberglass frames themselves, however, are stable and rust and weather resistant.
Fiberglass vs. Vinyl Windows in a Nutshell - Fiberglass windows are comparable to vinyl windows in performance and durability, but may be a little more expensive and may also require more maintenance.
Fiberglass is about 3 times stronger than aluminum and 9 times stronger than vinyl, and is more energy efficient because it doesn't conduct. Its rate of expansion is about the same as glass, to there's less torsion and air leakage. (Its expansion/contraction rate is about 1/3 that of aluminum, and 1/7 that of vinyl.) Fiberglass is an insulating material, so it doesn't need metal stiffeners, as vinyl often does, or a thermal break like aluminum windows.
You can easily find fiberglass windows with low U-factors and Energy Star certification. They do not corrode, rot, or warp and aren't susceptible to bugs, but they are about 10%-30% more costly than a mid-grade vinyl window.