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Fiberglass Windows Chicago

fiberglass windows chicago


Fiberglass is the best insulating material made into windows today. It is made from a simple polymer that is reinforced with thin strands of pulled glass. Air is trapped inside, and it makes for the best insulation of any window type. It also will not conduct heat or cold, so that its temperature should be neutral to the touch. Fiberglass is suitable for any climactic area and any temperature.

Strength and Durability

  • Fiberglass, unlike vinyl, wood and metal will not warp, crack, rot or bow. Its high tensile strength resists warping and twisting.
  • Fiberglass expands and contracts at similar rate as glass. This means there is less stress between the glass and frame which gives them a better fit, reduces air leakage and provides stability over temperature extremes. It is an extremely durable substance and will not succumb to temperature swings, moisture, structural damage or other types of abuse.
  • Fiberglass is inherently chemical-resistant: stands up to corrosive effects of salt, chemicals and atmospheric pollutants: Good for seacoast or industrial environments.
  • It has a high resistance to deterioration: resist to UV rays, moisture, rot, oxidation and rust, insects and woodpeckers.
  • The window apart from the glass will require almost zero maintenance.


The structure and nature of fiberglass windows is such that while being an excellent temperature insulator, it is also a great sound insulator. This means that with your windows closed and the appropriate glass in place, you will not be subjected to loud sounds outside your home.


Because the insulation of fiberglass is so effective, and because the temperature outside will not warm or cool the actual fiberglass in the window itself, excess condensation will not form in your home in any weather.


  • Unlike, vinyl, for a custom look, pultruded fiberglass windows can be painted to match your exterior interior paint or painted at the factory with a baked-on finish that won’t peel.
  • Gives you the aesthetic look of a wood window with the durability of fiberglass. Not “plastic” like some vinyl framed windows.
  • The profile of a fiberglass window is much narrower than vinyl or wood framed windows. This provides more glass area giving your home better views and more natural light.
  • The strength of fiberglass enables homeowners the ability to design large window units with thinner frames without reinforcing. This is especially help full with large projects such as sun rooms and other glass enclosures.

Energy Costs

For all these reasons and more, the most important benefit you will gain from having fiberglass windows is the savings from energy bills. It is estimated that on average, the difference in energy costs between fiberglass windows and any other type of window is 20 – 40%.

When fiberglass windows are required, Siding & Windows Group prefers to use products from Peachtree and Integrity by Marvin:

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Beauty. Performance. Comfort. There are plenty of good reasons to buy a Peachtree. But really, it all comes down to peace of mind. The satisfaction comes from choosing a window or door that you may never have to worry about again.


EasyCare® Glass

New EasyCare® Glass is available on all Peachtree windows. An exterior coating helps water sheet off, allowing the glass to dry faster with less spotting and streaking. Which means your windows will clean easier and stay clean longer.

Aller-Guard Weatherstrip

Aller-Guard weatherstripping forms a pollution-resistant seal that prevents outdoor dust and dirt particles from entering your home. It’s formulated to kill mold and mildew for a cleaner, more comfortable living environment. (Aller-Guard is owned and patented by Hope Global, Inc.)


fiberglass replacement windows chicago

Enduring Beauty

Bring the beauty of Peachtree windows and doors into your home, each handcrafted down to the smallest detail. From the warmth of hardwood interiors to the long-lasting beauty of aluminum and vinyl clad exteriors, Peachtree products are as enjoyable to look at as they are to look through.

Whole House Coordination

Windows. Patio Doors. Entry Doors. All coordinated. So no matter which Peachtree products you put in your home, you can be certain they’ll complement not only the beauty of your home, but each other as well.

Quality Construction

At Peachtree, they’ve compromised on nothing. Not on materials. Not on craftsmanship. Not on the people who build them. Nothing. That’s the only way they know how to build great products. Products that are durable, energy-efficient and easy to use.

Options for your Home

Beauty is often in the details. The little things that make a house your home. That’s why Peachtree offers thousands of different sizes, shapes and styles—each with the quality craftsmanship and elegant design that people have come to expect from Peachtree.

Superior Technology

Building the best windows and doors on the market means never following. It means always pushing. It means creating products around you and your needs. Products like Peachtree’s easy-to-clean EasyCare® glass, High-Performance Sill System and a pollution-fighting Aller-Guard weatherstrip.

Quality Materials

Peachtree knows you put a lot of care into what goes into your home, and so do they. That’s why they use only the finest materials in their windows and doors. You can see it in their warm wood interiors, low-maintenance aluminum clad exteriors and easy-to-clean EasyCare® glass.

Energy Efficiency

As an Energy Star® partner, Peachtree has determined that all products bearing the Energy Star® logo meet or exceed the Energy Star® guidelines for energy efficiency. Which means you can help cut your monthly energy bill and still keep your home comfortable year-round.

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Don't put off making one of the most energy efficient changes to your home. Replacing your windows with energy efficient windows can drastically reduce your energy bill. And trust this important investment to Chicago's top replacement windows professionals, Siding & Windows Group.

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Integrity by Marvin:

All Ultrex Series windows and doors feature Ultrex construction inside and out. Beautiful, easy to use and as low-maintenance as a material can get, Ultrex® provides exceptional aesthetics, outstanding durability, and standard ENERGY STAR-qualified performance. Six exterior finishes combine with pultruded fiberglass construction to offer virtually indestructible exteriors, while the low-maintenance classic white profiled interiors provide a beautiful classic appearance.

fiberglass windows chicago


  • Line of fiberglass windows and doors in both standard and special sizes
  • LoĒ2 and LoĒ3-366 insulating glass with argon gas
  • Low-maintenance, high-durability Ultrex exterior and interior
  • Stone White, Pebble Gray, Cashmere, Bronze, Evergreen and Ebony exterior finish options, or paint with no adverse effect on durability
  • Lite patterns and factory mulling allows you to easily create custom looks
What is Ultrex?
Durable, low-maintenance, strong, stable and tough: Everything you want your home to be, and everything that Ultrex delivers.
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Ultrex is Marvin’s proprietary creation made of pultruded fiberglass. Thin, strong cables of glass are saturated with special resin compounds, creating a remarkably durable material that vastly outperforms vinyl and roll-form aluminum. Because of its glass components, Ultrex has an extremely low thermal expansion rate; what little effect heat and cold has on it is matched by the glass in your window. So your double hung, glider or other Integrity unit remains tightly sealed without leaks, seal failures or stress cracks to diminish the units long-term performance and energy efficiency.
integrity windows graph 2
integrity windows graph 3Their patented finishing process mechanically bonds an impermeable acrylic cap onto the already virtually indestructible surface. This acrylic cap bonds to the pultruded fiberglass during curing and is up to three times thicker than our competitors’ finishes, providing better adhesion and resistance to scratches, marring and dings. Fading is prevented thanks to this superior patented finishing process which resists UV degradation, with five times more UV resistance than vinyl; This eliminates fading, chalking and streaking while allowing Integrity to offer darker finishes, like Bronze and Ebony, with total confidence in their long-term performance.

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