Fiberglass Windows

Windows That Weather It All

The climate in the Rockies puts windows to the test–scorching summers, freezing winters, and wild temperature swings. Fiberglass windows from Wyoming Building Supply are engineered to handle it all without cracking, warping, or losing efficiency.

Stronger than vinyl and low-maintenance, our fiberglass options deliver lasting durability and energy savings you can count on. Whether you’re remodeling your kitchen or managing a commercial project, our team is here to help you explore the best fiberglass windows for the job. We’ll even install them, ensuring they perform beautifully for decades.

Benefits That Go Beyond the View

Durability

Fiberglass resists warping, swelling, rotting, and corrosion, issues common with other materials in harsher climates. It expands and contracts at nearly the same rate as glass, reducing stress on seals and joints–protecting its lifespan. Our Modern, Elevate, and Essential lines use high-density fiberglass or proprietary Ultrex® material for maximum durability.

Energy Efficiency

Fiberglass frames are naturally insulating and can be filled with insulation for added performance. Tight seals help maintain consistent indoor temperatures, with many fiberglass windows meeting or exceeding ENERGY STAR® ratings. That means lower heating and cooling costs.

Low Maintenance

Unlike vinyl and wood, which can fade, chip, and crack without regular care and periodic maintenance, fiberglass windows maintain their shape, color, and performance with minimal upkeep. With occasional cleaning, you can keep your windows looking brand new.

Customizable

Choose from a wide range of finishes and styles, including options that mimic the look of wood. Thanks to fiberglass’s strength, it supports large glazed areas, making it an excellent choice for kitchen remodels and rooms where expansive views matter.

Environmentally-Friendly

Made from silica sand, a renewable resource, fiberglass requires less energy to produce than aluminum. Plus, thanks to its long lifespan, often 50 years or more, this material option reduces the need for replacements.

Brands We Trust

Fiberglass Window Installation

Fiberglass windows are engineered for exceptional performance, but they can only deliver that performance if they’re installed with precision. Even a slight misalignment can cause problems over time, such as gaps that let drafts in, seals that fail under the temperature swings of the Rockies, or frames that put stress on the glass.

A flawless fit ensures the frame and glass move together as one, maintaining the airtight seal that gives these windows their superior insulation and energy efficiency. That’s why Wyoming Building Supply offers professional fiberglass window installation services. Our licensed professionals use meticulous measurements, advanced tools, and proven techniques to ensure your windows perform as promised–keeping your home comfortable and your utility bills low.

Transform Your View

Fiberglass Windows for Homeowners

Building a new home or making updates? Fiberglass windows are a great option, and a smart choice for larger, unobstructed views, minimal maintenance, and long-term energy savings. Popular styles we supply and install include single hung, double hung, casement, awning, sliding, bay & bow, corner windows, and even specialty shapes.

Fiberglass Windows for Commercial Projects

The strength and consistency of fiberglass makes it a great option for builders and contractors. It allows larger glass sizes, can withstand heavy-use environments, and reduces long-term maintenance costs. Team up with Wyoming Building Supply for reliable delivery and trained installation crews that help your projects stay on schedule.

Why Customers Love Wyoming Building Supply

Everyone was extremely helpful and patient every step of the way! They listened, suggested, listened, explained… then brought our vision to life. We definitely recommend Wyoming Building supply and will contact them for any future projects.

Casey Cook

Wyoming Building Supply has an outstanding team, both in the field and in the office. We've been smoothly coordinating the phased replacement of hundreds of windows for a local multifamily project, and the process has been seamless. They are responsive, communicative, and respectful of the residents and their homes during the window replacements. Additionally, their invoicing is prompt and transparent, with no surprises. Our staff has even started using WBS for their own home improvements, further solidifying the excellent service we've experienced. Thank you!

Daniel Appel

I shopped around for new kitchen cabinets and chose WY Building Supply over the others, and I’m so glad I did. Great quality at a competitive price. The service is what won me over. Allie came out and did measurements the next day, and according to my contractor, the measurements for the cabinets were spot on. Communication and responsiveness during the entire process was wonderful too. Thank you Allie, Hunter and the entire team. I will definitely be a repeat customer.

Kelly Morgan

Fiberglass Windows FAQs

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From Design to Installation

Design

Collaborate with our in-house design specialists to bring your architectural vision to life. We utilize advanced 3D rendering technology to help you visualize your layout, navigating options in door styles, sidelights, transoms, and hardware finishes. Our goal is to ensure your new entry system matches your home’s character—whether it’s a rustic mountain lodge, a sleek contemporary build, or a traditional suburban home—while meeting your specific needs for privacy, natural light, and airflow.

Select

Explore our curated range of quality products from brands we trust for their performance in harsh, high-altitude climates. We help you compare construction methods, such as the rot-resistance of fiberglass versus the classic weight of solid wood, and glass packages tailored to your home's solar orientation. From premium wood-clad options to high-security steel, we help you choose the materials that offer the best return on investment (ROI) and performance for your budget. We also provide a wide selection of Countertops and Cabinets to ensure your interior remodel is cohesive and professional.

Deliver

Enjoy a seamless and efficient in-state delivery process handled by professionals who understand the value of your materials. Our local logistics team manages the transport of your doors and hardware, ensuring every component—from the heavy pre-hung frames to the delicate glass inserts—arrives on-site in perfect condition. By using our own specialized fleet and custom racking systems, we avoid the shipping delays, "lost in transit" issues, and freight damage often associated with third-party carriers, keeping your project timeline strictly on schedule.

Install

Sit back and relax as our experienced professionals transform your space with white-glove installation services. Our crews are factory-trained to work efficiently, handling the intricate leveling, shimming, and specialized sealing required for a lifetime of draft-free performance. We treat your property with the utmost respect, maintaining a clean, debris-free job site and ensuring a final result that meets our 50-year reputation for excellence in the Wyoming building industry.

Serving Wyoming & Beyond

Since 1976, we've proudly served the Rocky Mountain region from our five locations: Casper, Cheyenne, Sheridan, and Cody in Wyoming, plus Rapid City in South Dakota. For your convenience, our service area extends to northern Colorado, southern Montana, and western South Dakota.