Pella’s Impervia fiberglass window line is a favorite among Dane County residents. In fact, it’s one of our favorites, too. Fiberglass is a material that’s used for many products — including bridges and boats — because of its durability and strength. This makes it a natural choice as a material for windows. Pella offers a proprietary fiberglass material for their windows, and it’s the strongest material you can choose for your replacement windows Let’s take a look at the benefits of these windows, before taking a peek at window styles and colors … Dependable Durability & Strength Pella’s fiberglass windows are resistant to dents, bends and breaks. In addition, they have virtually zero expansion and contraction, which improves energy efficiency and reduces risk of seal failure. Simply put, these fiberglass windows deliver long-term stability and operation. They’re Virtually Maintenance Free Pella’s fiberglass windows won’t rot or corrode. In addition, fiberglass is a material that’s naturally resistant to water and insects. The need to paint your windows has been eliminated, as fiberglass also resists fading, chipping