Seattle Fiberglass Windows
Fiberglass windows are crafted from high-quality glass fibers, using materials like silica sand, limestone, and soda ash. This blend is intricately woven and set through a resin bath before being cured in a high-temperature die. Our unique manufacturing process results in windows that are not only strong but also offer superior insulation. With options for either foam-filled or hollow core frames, these windows maintain consistent temperatures by expanding and contracting at the same rate as the glass pane they encase. This feature significantly reduces air leaks and enhances durability, making fiberglass windows an excellent choice for Seattle homes. Opt for these energy-efficient windows to enhance your home’s curb appeal while reducing your carbon footprint and saving on maintenance over time.
Why Choose Fiberglass Windows?
| Material | Durability | Maintenance | Energy Efficiency | Cost | Environmental Impact | Sound Insulation | % Frame to Glass Ratio |
| Vinyl | Moderate | Low | Good | $ | Moderate | Good | Moderate |
| Fiberglass | High | Low | Excellent | $$ | Low | Excellent | High |
| Wood | Moderate | High | Good | $$ | Low | Good | Low |
Fiberglass Window Benefits
- Fiberglass windows are the pinnacle of energy efficiency, making them the right windows for any energy-conscious homeowner.
- Known for their durability, these windows can last between 50-80 years, ensuring more money saved over time.
- Resistant to extreme temperatures and extreme heat, fiberglass does not warp, crack, or rust, requiring little maintenance.
- Available in a variety of styles and interior colors, fiberglass windows enhance your home’s curb appeal and suit any design preference.
- Fiberglass is an environmentally friendly choice, helping to reduce your carbon footprint and avoid harmful chemicals.
The Finest Fiberglass Manufacturer Chosen For You
With more than 30 years in the window industry, we know what separates a good window manufacturer from a great one. That’s why we’ve chosen Milgard as our fiberglass partner. They’ve earned our trust through consistent quality, outstanding warranty support, and a commitment to innovation that keeps them ahead of the field — most recently with the launch of their next-generation C700 Series.
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The Milgard C700 Series is a next-generation fiberglass window line built for homeowners who want strength, style, and long-term performance. Fiberglass is one of the most durable and energy-efficient frame materials on the market today. Made primarily of silica sand, it expands and contracts at nearly the same rate as glass, which means tighter seals, fewer drafts, and less wear on caulking over time. With a clean modern profile, expanded color options, and enhanced energy performance, the C700 is a top-of-the-line replacement window, purpose-built for Pacific Northwest homes.
Features and Benefits:
- Built to last a lifetime. Fiberglass is one of the toughest window frame materials on the market, standing up to decades of Seattle weather without swelling, rotting, or warping. Once it’s in, it takes care of itself.
- Exceptional energy performance. Every C700 comes standard with Milgard SunCoat® Low-E2 glass and delivers up to 10% better thermal performance than its beloved predecessor, keeping your home comfortable year-round and your energy bills in check.
- A noticeably quieter home. The C700’s laminated glass options dramatically reduce outside noise, so whether you’re near I-5, a flight path, or a busy neighborhood street, you’ll feel the difference the moment you close the window.
- Designed to look like it belongs. With six frame colors, matching hardware finishes, and a clean modern profile, the C700 complements any architectural style, from a classic Seattle Craftsman to a sleek contemporary build. It’s a window that improves your home’s curb appeal inside and out.
- Peace of mind, built into every unit. The C700 is backed by Milgard’s Limited Lifetime Warranty for residential homeowners, with the option to upgrade to a Full Lifetime Warranty at the time of purchase. It’s a significant investment, and Milgard stands behind it.
| Available Styles | Frame Colors | Grid Styles | Grid Patterns | Glass Options | Hardware Features | Hardware Finishes |
| Horizontal Slider | White | 5/8″ Flat | Standard | SunCoat® Low-E2 (standard) | SmartTouch® auto-locking hardware | White |
| Single Hung | Black | 15/16″ Sculptured | Standard Half | SunCoatMAX® | Casement: dual-arm steel rotary operator, multi-point lock | Black |
| Casement | Bronze | Simulated Divided Lite (SDL) | Valance | Tinted Glass Options | Awning: single-arm scissor operator, dual lever lock | Bronze |
| Awning | Bark | 2-3/8″ Check Rail | Perimeter Pane | Obscure Glass Options | Bark | |
| Picture | Adobe | Perimeter Corner | Adobe | |||
| Steel Gray | Steel Gray | |||||
| Satin Nickel (upgrade) | ||||||
| Oil Rubbed Bronze (upgrade) |
Comparing Fiberglass to Vinyl Windows
Compared to other window materials, we consider fiberglass the highest quality material available for your Seattle home. It provides optimal levels of performance and durability, along with many design options.
While fiberglass is more energy-efficient and durable compared to vinyl window materials, it’s also significantly more expensive. Because of this, we recommend fiberglass windows to homeowners who want the best material money can buy and vinyl windows for homeowners who desire comparable performance at a more affordable price. Finding the balance between performance and initial cost results in the maximum ROI from your new windows.
Fiberglass Window Frames Available in a Range of Styles
It doesn’t matter what window style you’re looking for. At Lake Washington Windows and Doors, we offer vinyl replacement window options in 6 of the 7 primary home window styles, including
Picture Windows
Fixed and non-opening, picture windows provide a clear, unobstructed view of the outdoors, allowing an abundance of natural light. They enhance the architectural aesthetic of your home, serving as a striking design focal point.
Casement Windows
These windows are hinged at the side and open outward, offering superior ventilation. Easy to operate with a crank or lever, casement windows boast a tighter seal for excellent insulation.
Single-Hung Windows
Featuring a fixed top sash and a movable bottom sash that slides vertically, single-hung windows are a cost-effective and popular choice. They provide a traditional look and are simpler to install than more complex styles.
Awning Windows
Hinged at the top and opening outward from the bottom, awning windows shield against rain while open and boost ventilation. Their unique design is ideal for adding airflow above doors or other windows.
Sliding Windows
With one sash sliding over another horizontally, these windows save space while offering ample ventilation. Perfect for areas with limited exterior space, like walkways, patios, or along busy streets.
Top-Rated Window & Door Replacement Services
At Lake Washington Windows and Doors, we offer the highest quality windows and unparalleled customer service, with over 800 5-star reviews. With each installation, our exclusive Leak Armor Installation provides superior protection around your window openings. When you choose us for your window installation project, you can be sure that you’re getting the best.
Financing Options with Convenient 10 Minute Approvals
In addition to special offers and promotions, ask our sales representative about our quick, digital financing application process. From low-interest traditional loans to no down-no payment-no interest deferred financing plans, we can help you fund your replacement window project so you can mobilize your cash for other investments. We are a proud partner of GreenSky, one of the largest lenders for the home improvement industry. See how much you can be pre-approved for.
Every Window & Door Includes a Limited Lifetime Warranty
The beauty of working with the top window manufacturers in the industry is the support you can expect before, during, and after installation. Milgard offers a limited lifetime warranty. However, the likelihood that you’ll need to take advantage of the warranties is low.
Milgard Lifetime Warranty Guarantee
Milgard’s award-winning windows and doors are built to last. However, if you ever encounter an unexpected problem, you can rest assured that their lifetime warranties cover your purchase.
Every Installation Includes Leak Armor Commercial-Grade Protection
Our exclusive Leak Armor protection is included with every window we install. Developed through thousands of customer installations and years of experience, we utilize multiple layers of flashing, pans, and sealants in a specific manner to provide commercial-grade sealing to residential homes.
Fiberglass Window FAQs
Are Fiberglass Windows worth it?
The popularity of fiberglass windows is higher than ever. While the upfront cost is more significant, fiberglass provides benefits that vinyl windows do not. If you’re willing to spend the money upfront and reap the return on investment over time, then fiberglass windows are a worthwhile option for you and your home.
What style and color options are available with fiberglass windows?
Fiberglass is a versatile window frame material that can be molded and configured into most window styles. Milgard offers a range of interior and exterior colors, along with several different glass textures and window grids. Visit our window style page to explore the fiberglass options we provide.
Are fiberglass replacement windows durable?
Fiberglass windows do not damage easily. They will resist dents, scratches, warping, rotting, and corroding. The material is also strong and rigid, allowing fiberglass windows to be up to eight times stronger than vinyl windows and requiring much less maintenance.
How long does the fiberglass window installation process take?
At Lake Washington Windows and Doors, our installation process is down to a science. When embarking on a project with new customers, we generally schedule 2-5 days for installation, depending on the project size.
