As a building material, fiberglass is nothing new. It’s been floating boats and strengthening ladders for years. In the window industry, however, it’s the latest addition to a range of finish options. The most popular fiberglass windows are wood windows with exterior fiberglass cladding but 100% fiberglass windows are also available. Fiberglass windows currently comprise about 4% of the market and the percentage is growing each year.
Fiberglass windows are a popular alternative to metal or wood windows for good reason: they are strong, durable, long-lasting, maintenance free, energy efficient, have low thermal expansions, and are economical. Fiberglass is made of thin, strong cables of glass, saturated with specially compounded resins and fiberglass won’t discolor, warp, rot, dent, or rust over time.
For renovation work, fiberglass windows are a very good choice. In addition to the above benefits, two characteristics separate them from other window alternatives and make them especially appropriate for this specialized work.
First, in a restoration project, window profiles (stiles, rails, and muntins) often need to simulate older, wooden windows with narrow profiles. Fiberglass is 3.5 times stronger than wood composites and 3 times stronger than wood. Because of it’s superior strength, fiberglass profiles are narrower than most replacement windows and are the perfect solution when a traditional look is needed. And, unlike wood windows, they never need to be painted or scraped.
However, fiberglass windows can be painted for aesthetic reasons.
The second important feature of fiberglass windows is that although painting isn’t necessary for protection, they are paintable. Over the course of a lifetime, historic buildings undergo a number of color transformations. From generation to generation, color schemes vary and what is popular during one decade is often out of favor the next. Because color is so important in renovation projects, fiberglass windows give older buildings the ability to change colors. From one generation to the next, fiberglass windows – like wood windows – are chameleons, they can change color whenever a building does. In contrast, once a metal or vinyl window is installed, it can’t be painted and the building color must always be coordinated with the unchangeable window color.
For renovation projects that need to meet high standards, restoring or recreating original wood windows is the only window treatment possible. But for rehabilitation projects with less-demanding standards or projects where no original wood windows are extant, installing fiberglass windows makes a lot of sense: they are more durable than wood, they’re proportionally correct, and they require no maintenance but can be painted.
In the future, more restoration projects will discover that fiberglass windows fulfill many needs. Even better, they don’t break the budget.
Jerri Holan, FAIA, is an award-winning architect with an old-fashioned mission: to create buildings connected to their context and to express these connections gracefully. She has received awards from the National Trust, the American Institute of Architects, the California Preservation Foundation, the Art Deco Society of California, the Berkeley Architectural Heritage Association, and the Oakland Heritage Alliance. See the original post from Jerri Holan, FAIA here.