Fiberglass vs Aluminum Windows
If you are comparing fiberglass vs. aluminum windows, here are four important areas to constrast before buying. See our window cost estimator for more pricing specifics.
| Comparison Category | Fiberglass Windows | Aluminum Windows |
|---|---|---|
| Average Installed Cost | $1,150 to $1,850 | $1,050 to $1,650 |
| Strength & Durability | Excellent for nearly all residential homes | Excellent; generally the strongest frame material |
| Appearance | Traditional residential look with moderate frame thickness | Thin, modern frames with larger glass area |
| Color Options | Wide variety of colors and finishes | More limited color selection |
| Energy Efficiency | Excellent; among the most energy-efficient frame materials | Good with thermal breaks, but generally trails fiberglass |
| Best For | Homeowners seeking premium efficiency and long-term performance | Modern designs and hot climates where maximum frame strength is important |
⭐ PRO TIP REMINDER - always collect 2 to 3 project quotes, compare pricing, and save $$$! ⭐
Fiberglass vs Aluminum Windows Cost Comparison
Both of these options will be more expensive than a comparable vinyl frame and a bit less than a wood clad frame. (It should be noted that most wood clad frames use an aluminum or a fiberglass as the exterior cladding material.) Each of these offers good long term value, given a quality manufacturer and installation. Expect a mid range aluminum or fiberglass window to run $1,150 to $1,650 installed for a typical sized double hung window. The Marvin Infinity and Integrity are two highly regarded fiberglass frames - check Marvin windows prices for cost breakdowns and analysis on these two options.
Fiberglass vs Aluminum Windows Strength
Aluminum windows are generally considered the strongest and most durable of all window frames. This is the primary reason that they are a good choice for hot desert climates - the material won't bend and warp like a poorly made vinyl extrusion can. However, fiberglass is very strong as well, certainly strong enough for 99% of all residential homes. These two materials top the list from a strength and druability point of view and either one is a great choice (if these options fall within your budget).
Window Cost Calculator
Answer a few quick questions to estimate your project cost.
Style Comparisons
Aluminum frames have their own style and look to them - specifically a more modern or commercial look and feel. They generally have thinner frames because they are so strong, which allows for more glass area and a more open, sleek appearance. Fiberglass windows are more of a mixed bag, they tend to look almost indistinguishable from vinyl windows, although because they are stronger than most vinyl frames, they can be thinnner. Generally, they are a little thicker than aluminum and come in a variety of colors and finishes, where aluminum tends to offer less color options.
Fiberglass vs Aluminum Windows On Energy Efficiency
Poor energy efficiency is the big knock on aluminum and the primary reason why many homeowners opt for another type of frame material. Most aluminum windows are actually much more energy efficient than older ones because they are thermally broken. However, they still lag behind most other materials in terms of performance numbers. Fiberglass, on the other hand, is quite energy efficient and well made models and window series offer some of the best performance numbers out there. There tends to be debate amongst contractors and other industry experts as to whether high end fiberglass or high end vinyl windows offer the best numbers, but fiberglass certainly tops aluminum in this category. Vinyl vs Fiberglass Windows
Bottom Line
Aluminum is best left to very warm climates or for homeowners that love the overall commercial or modern look of this material. Fiberglass composites are great options for any homeowner that wants a quality window and can afford the price. Not all fiberglass windows are equal - check on what we feel are the best fiberglass windows available.
Window Material Choices In Arizona
Fiberglass windows are excellent and they will work virtually anywhere, but for the desert climate I'd go with aluminum. Since winter heat loss isn't much of a concern in places like southern Arizona, aluminum's lower insulating value isn't nearly as important. What it does offer is exceptional durability and strength under relentless sun and extreme heat. Having grown up around in Arizona, I've seen just how hard that environment can be on windows, and quality anodized aluminum has always held up well.If you’re going to go with vinyl, it had better be VERY well made.
Dane - Site Editor - from 2026
Join 1,000+ Homeowners Sharing Quotes And Reviews
Have a question, review, or price quote to share? Submit your comment below.