what is Fiberglass?

Fiberglass is not a new material, it’s found everywhere, from boat hulls to home insulation to car bodies.

We call it a miracle material because it surpasses other materials in strength and longevity, which is why it is the cornerstone of our fiberglass window frames.

Fiberglass, a common building material, is used in boats for its strength and resistance to rot.

how is fiberglass made?

It’s a science that our team of engineers have perfected.

It’s proprietary resin, reinforcing fiberglass fabric, and fine glass fibers — all heated, pressurized, and pulled through custom molds to create individual window parts. These  pieces create our fiberglass window frame, which differentiates us from cheaper and weaker alternatives.


You want your window to be strong, here’s why.

Expansion and contraction in a window can be bad, it causes air leakage, seal failures and a number of other problems you don’t want to have.  A fiberglass replacement window is so strong that it has the lowest expansion and contraction of all materials which reduces window failures.

Chart: Coefficient of Thermal Expansion (Source: Internal testing using ASTM D696 Aluminum)

fiberglass is stable

Our fiberglass windows are made of materials that move in harmony through hot summers and cold winters. Proportional movement across all these materials reduces the risk of broken and failing seals.

Shrinking or expanding frames due to thermal expansion are the main cause for window failures including:

  • Seal failure and condensation
  • Air leakage
  • Difficulty opening and closing

Fiberglass doesn’t expand and contract away from the glass like other materials, which reduces window failures.


Wood where you want it, Fiberglass where you need it.

Fiberglass is the best material to give you protection from the weather, while the wood interior adds beauty and character to your home.

Whether you are looking for a stained, white, or special color, the ability to choose a wood interior while having the durability and performance of fiberglass on exterior is why many call Beechworth the best window brand.

Onyx Black Beechworth fiberglass replacement window with wood interior

“Homeowners can get the warmth of wood and functionality of fiberglass at an achievable price”

Contractor's Point of View

“It shouldn’t cost more to get a quality product.”

Beechworth Warranty Details

The average cost of Beechworth Windows beat the national average cost for all-wood windows by 12%.

  • 20 years on the glass components
  • 15 years on accessories: exterior trim, locks, lifts, hinges and handles
  • 15 years on exterior finish in all colors

For more warranty information or to get a quote, message us or talk to your contractor. We can also help you find a contractor.

Building on 130 years of Experience

In the tradition of our parent company, James Hardie, we’ve innovated new ways to manufacture windows. Our fiberglass replacement windows solve the issues of old and low-quality windows and are backed by an industry leading building material manufacturer.

Start Your Home Transformation Today

Get a FREE estimate from one of our top-rated contractors.

Find a contractor

or start a project plan