Choosing new windows for your home is an important decision that requires careful consideration of the pros and cons of different window materials. Two popular options for homeowners are fiberglass and vinyl windows. This buying guide will compare fiberglass and vinyl windows to help you determine which is the better choice for your home remodeling or replacement window project.
What is Fiberglass?
Fiberglass windows are made by reinforcing plastic resin with tiny glass fibers. The result is a composite material that combines the durability and strength of glass with the insulation properties and flexibility of plastic.
Fiberglass offers several benefits compared to traditional window materials:
- Strong and durable – Fiberglass is highly impact resistant and does not rot, warp or crack over time. The material is very rigid and robust. Fiberglass windows can last over 30 years with proper care.
- Energy efficient – The fiberglass construction provides effective insulation against heat and cold. Most fiberglass windows have a thermal resistance (R-value) between R-2 to R-3.
- Noise reduction – The tight seal and dense material blocks outside noise penetration very effectively. Fiberglass windows can reduce noise by up to 50% compared to single pane glass.
- Low maintenance – Fiberglass won’t peel, blister or flake like painted wood windows. Just an occasional washing is all that’s needed to keep fiberglass windows looking fresh.
- Great aesthetics – Fiberglass can be made into beautiful windows with crisp details and attractive finishes. Different stain colors allow matching most home styles.
What is Vinyl?
Vinyl is a plastic material made from polyvinyl chloride (PVC) resin combined with additives for durability. Vinyl is used to make window frames and sashes that are hollow with strengthening inserts inside.
Some benefits of vinyl windows are:
- Affordable price – Vinyl is less expensive than wood, fiberglass and aluminum. Vinyl is a lighter weight plastic so windows are cheaper to manufacture and transport.
- Color options – Vinyl comes in a wide range of standard and custom color options. Different dyes can be added to the vinyl formula.
- Low maintenance – Vinyl resists rot, corrosion, decay and insects. It won’t warp or crack over time. Just occasional cleaning is required.
- Energy efficient – Vinyl is a good thermal insulator. Most vinyl windows have a R-value between R-2 to R-3.
- Noise reduction – Vinyl material helps block sound transmission. Triple pane vinyl can reduce outside noise by up to 50% or more.
Fiberglass vs Vinyl Windows Comparison
Now that you understand the basics of fiberglass and vinyl for windows, let’s compare the two materials in detail across some key factors:
Strength and Durability
Fiberglass
Fiberglass has high impact strength and is very scratch resistant. The reinforcing glass fibers interlaced through the resin create a rigid structure. Fiberglass won’t crack, peel, blister or flake over decades of use. It maintains its structural integrity through a wide temperature range from frigid cold to intense heat.
Vinyl
Vinyl is susceptible to impact damage and scratches more easily than fiberglass. Cheaper vinyl may warp, bow and bend over time as the plasticizers in the formula break down. In very cold climates, vinyl can become more brittle and crack. High heat also causes vinyl to soften and lose rigidity.
Winner: Fiberglass wins for higher strength and longevity in all weather conditions. Fiberglass windows will outlast vinyl counterparts by many years.
Energy Efficiency
Fiberglass
Most fiberglass windows are filled with argon or krypton gas between multiple panes which further enhances insulation capability. Advanced coatings can boost R-values above R-5. Fiberglass frames form an airtight seal and prevent thermal conduction.
Vinyl
Vinyl’s natural insulating properties make it suitable for energy efficient windows, especially in moderate climates. Additional foam filler and advanced glazings push R-values to around R-3. Vinyl forms a tight seal to reduce air leakage.
Winner: Draw – High end designs from both materials can meet stringent energy efficiency standards. It depends on the specific window construction.
Noise Reduction
Fiberglass
The density and rigidity of fiberglass blocks sound waves very effectively. Laminated glazing provides additional acoustic insulation. Well-constructed fiberglass windows reduce outside noise penetration and improve indoor quietness.
Vinyl
Vinyl’s plastic composition helps dampen noise. Multi-pane glazing further reduces noise transmission. With triple pane designs, vinyl windows can cut external sound by up to 50% for notably quieter indoor ambiance.
Winner: Draw – Both materials do an excellent job reducing outside noise when properly engineered.
Appearance and Styles
Fiberglass
Fiberglass windows can closely replicate the aesthetics of wood windows but without the high maintenance. With different staining, fiberglass is able to match many architectural styles from modern to rustic. But color and finish options are not as varied as vinyl.
Vinyl
Vinyl allows extensive customization of colors, textures and finishes. Wood grain patterns, metallic coatings and other options enable matching any decor. Vinyl can even be shaped into arched, geometric and radius designs. But vinyl lacks the visual depth and richness of wood.
Winner: Vinyl offers nearly unlimited styling versatility from traditional to contemporary for any home exterior.
Costs and Value
Fiberglass
Fiberglass windows are priced higher than vinyl but lower than wood or aluminum. Their high durability equates to lasting value. Good quality fiberglass windows have a cost premium over vinyl but with a 30+ year lifespan.
Vinyl
Vinyl is the most affordable framing material. Simple vinyl windows start under $200. More complex vinyl designs are priced substantially lower than comparable levels of wood or fiberglass. Vinyl offers value but has a shorter service life.
Winner: Vinyl if budget is the priority. Fiberglass for long term investment if budget allows.
Weather Resistance
Fiberglass
The composite formula makes fiberglass highly weather-resistant. It does not expand and contract with temperature swings. Fiberglass resists UV damage, moisture and retains its rigidity in all climates. Properly installed, fiberglass windows last decades.
Vinyl
While Vinyl holds up reasonably well, extreme heat and cold conditions can make it more prone to cracking and seal failure. Prolonged UV and moisture exposure degrades vinyl over time. Frequent expansion and contraction accelerates wear. Vinyl may need replacement sooner in harsh climates.
Winner: Fiberglass maintains its integrity and performance through all weather extremes.
Maintenance Requirements
Fiberglass
Other than occasional cleaning, fiberglass windows are maintenance-free. Their durable construction in resistant to weathering and corrosion. No painting, staining or refinishing over their lifespan.
Vinyl
Vinyl also requires little annual upkeep – just occasional washing and inspection of seals. It may need protective coatings in seaside or desert environments. But overall vinyl is a low maintenance option.
Winner: Draw – both materials are very low maintenance compared to wood windows.
Fiberglass Window Brands
When comparing different brands and models of fiberglass windows, look for signs of quality:
- Multiple layers of UV protection
- Strong composite construction with a high percentage of glass fiber
- Stainless steel or other non-corrosive hardware
- High performance insulated glass units
- Robust frame and sash design
- Warranty of at least 10 years on parts
Some of the top fiberglass window manufacturers include:
Milgard – Known for durability and energy efficiency. Went into fiberglass in 2009. Milgard fiberglass windows have high R-values and custom grid options.
Pella – A leading brand for 94 years. Pella uses premium materials and advanced engineering. Their fiberglass lines like Architect Series meet stringent energy standards.
Marvin – Family-owned and operated business established in 1912. They pioneered the first fiberglass window in 1992. Marvin fiberglass models like Integrity feature sturdy construction.
Jeld-Wen – In operation for 60 years making high quality windows and doors. Product collections like Jeld-Wen Siteline use durable fiberglass framing.
Andersen – One of the largest window makers, in business for over 115 years. Units like A-Series feature Fibrex fiberglass material developed by Andersen.
Weather Shield – Part of the Weathershield Windows family producing windows since 1946. Their premium Symmetry line utilizes fiberglass for energy efficiency and strength.
Vinyl Window Brands
The quality of vinyl windows can vary so it’s important to stick with reputable established brands. Features to look for include:
- 100% virgin vinyl formula, no reground plastics
- Strong multi-chamber frame and sash design
- Stainless steel reinforcement for stability
- High performance sealed glass units
- Weatherstripping and heavy-duty hardware
Some well-known vinyl window manufacturers are:
Jeld-Wen – A leading brand offering affordable, energy efficient vinyl windows in many styles including casement and double hung models.
Atrium Windows – Manufacturing vinyl windows for over 25 years with durable frames and high energy efficiency up to R-5 levels.
Alside – Producing vinyl windows since 1947 noted for strength, efficiency, easy operation and low maintenance.
Simonton Windows – Around since 1946, they use premium ProFinish vinyl exterior and performance glazing. Models like Asure offer advanced features.
Ply Gem Windows – Using top quality vinyl compounds, Ply Gem makes reliable vinyl windows under brands like Great Lakes Window.
MI Windows – A respected brand started in 2012 focused on high quality vinyl window engineering and craftsmanship.
Soft-Lite – Manufacturing affordable and energy saving vinyl windows for over 35 years with double-lifetime warranties.
Key Considerations When Deciding Between Fiberglass and Vinyl Windows
Choosing fiberglass versus vinyl windows involves weighing several important criteria:
- Installation Location – Fiberglass performs better than vinyl in extreme climates that experience wide temperature variations.
- Budget – Initial cost is lower for vinyl. But fiberglass offers greater long term value from a lifespan double that of vinyl.
- Energy Priorities – Both can meet ENERGY STAR. Look at the specific R-values and features to determine efficiency.
- Noise Reduction – Both excel at sound dampening. Focus on glazing thickness and construction techniques.
- Appearance – Vinyl has near unlimited color and finish options. Fiberglass works well for a wood look.
- Lifespan – Fiberglass averages 30-40 years, while vinyl lasts around 15-20 years before replacement is needed.
- Maintenance – Not a major distinction. Both require minimal annual upkeep without re-painting.
- Sustainability – Fiberglass is considered more eco-friendly than PVC vinyl that has higher embodied carbon.
- Quality Reputation – Look for proven brands that back their windows with a strong multi-year warranty.
Pros and Cons of Fiberglass Windows
| Pros | Cons |
|-|-|
| Extremely durable, resistant to impacts, scratches, warping | Higher upfront cost than vinyl |
| 30+ year lifespan | Less size and color options than vinyl |
| Excellent thermal insulation and energy efficiency | Heavier than vinyl which adds to transport costs |
| Maintains strength and performance in all weather extremes | Can be difficult to source skilled installers in some areas |
| Great noise dampening abilities | Does not blend into frame as well as vinyl when painted |
| Very low maintenance needs | Limited recycled content availability |
| Resists moisture, rotting and pests | |
Pros and Cons of Vinyl Windows
| Pros | Cons |
|-|-|
| Very affordable price point | Shorter lifespan of around 15-20 years |
| Huge selection of colors, finishes and styles | Subject to warping, cracking and seal failure in extreme heat or cold |
| Lightweight for easy transportation and installation | Not as rigid and durable as fiberglass |
| Easy to match with painted frame | Less effective noise insulation than fiberglass |
| Made from recyclable materials | Poor resistance to impact damage |
| Simple designs available for DIY install | Can degrade and discolor over time from UV exposure |
| Wide range of sizes from small to very large picture windows | Limited color stability; fade over time |
Cost Comparison of Fiberglass vs Vinyl Windows
Fiberglass windows are generally 20% to 50% more expensive than vinyl windows depending on materials, features and size. Here are some typical costs:
- Basic 24″ x 36″ vinyl double hung window – $175 to $250
- Basic 24″ x 36″ fiberglass double hung window – $275 to $375
- High performance 36″ x 48″ vinyl casement window – $400 to $600
- High performance 36″ x 48″ fiberglass casement window – $600 to $900
- Custom vinyl bay window 60″ wide x 36″ high – $1,500 to $2,200
- Custom fiberglass bay window 60″ wide x 36″ high – $2,200 to $3,200
Higher cost fiberglass windows pay for themselves long-term when you factor in their significantly longer service life compared to vinyl. The extra upfront investment results in lower lifetime cost per year given the durability of fiberglass.
Should I Choose Fiberglass or Vinyl Windows?
Fiberglass windows are the better choice if you prioritize:
- Durability and longevity
- Maintaining structural integrity in all weather
- Energy efficiency and noise reduction
- A wood-like aesthetic
- Environmentally responsible materials
- Lifetime value over upfront cost
Vinyl windows make more sense if you want:
- The lowest upfront price
- A huge variety of colors and finishes
- Lightweight windows for DIY installation
- Simple designs including radius shapes
- Good insulation at a moderate price point
- Short term savings over lifetime value
Many homeowners opt for fiberglass windows for critical living spaces like the master suite where quality matters most. Vinyl works well for secondary rooms, kids bedrooms or garage windows where cost is the driving factor.
FAQs About Fiberglass and Vinyl Windows
Is fiberglass better than vinyl for windows?
Fiberglass is superior to vinyl in terms of strength, durability and weather resistance. But vinyl offers far more style customization. It depends on your priorities such as budget, appearance and efficiency.
How long do fiberglass windows last compared to vinyl?
The average lifespan of fiberglass windows is 30-40 years. Vinyl windows last around 15-20 years before replacement is needed. Fiberglass has double the longevity of vinyl.
Which is more energy efficient between fiberglass and vinyl windows?
It depends on the specific window construction, not necessarily the frame material. Both fiberglass and vinyl can meet ENERGY STAR requirements with the right glazing, gas fills and seals.
Can you paint fiberglass windows?
Fiberglass windows accept paint but lose the crisply stained wood-like appearance that is their aesthetic advantage over vinyl. Most homeowners opt to keep the factory applied fiberglass stain finish.
Do fiberglass or vinyl windows cost more to install?
Fiberglass window installation may be 10% to 15% more than vinyl. Fiberglass is heavier and requires extra care not to damage the rigid frame and sash components when handling.
What is the R-value of fiberglass vs vinyl?
Basic R-values range from R-2 to R-3 for both materials. But advanced designs with triple glazing, gas fills and foam insulation can achieve R-5 or higher for fiberglass and vinyl windows.
Are fiberglass windows scratch resistant?
Yes, the glass fibers reinforce the resin to create a very scratch resistant surface. Fiberglass stands up well to kids, pets and general wear and tear without showing mars and scratches.
Can you repair fiberglass window frames?
Minor chips and cracks in fiberglass can be filled and touched up. But major damage requires replacing the entire frame or sash. Fiberglass repair is limited compared to wood window restorations.
Do fiberglass or vinyl windows offer better noise reduction?
Both materials provide excellent noise blocking when properly constructed with laminated glass. Look at glazing thickness rather than just the frame material to determine sound dampening capability.
Are insects attracted to vinyl windows?
Some types of ants, cockroaches and stink bugs can be attracted to chemical compounds used in cheaper vinyl. Higher quality vinyl with UV inhibitors is less susceptible to pest issues.
Conclusion
When selecting replacement or new construction windows, fiberglass and vinyl frames each have unique advantages. Fiberglass is an exceptional choice where longevity, extremely high performance and attractive wood-like aesthetics are desired. Vinyl offers affordability, quick installation and limitless style options. Carefully weigh your priorities before deciding between durable fiberglass vs. affordable vinyl windows. Be sure to read unbiased reviews and get quotes from multiple window companies in your area before making your final window selection. Investing in quality windows from reputable brands will increase comfort and enhance your home’s beauty and value for many years to come.