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Fiberglass Windows

Fiberglass Windows in the GTA and Southern Ontario

At Window Experts, we supply and install Inline fiberglass windows across the GTA and selected Southern Ontario communities. Our full-time, in-house crew handles every installation, and a free in-home estimate lets you review products, measurements and installation requirements before you decide.

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Window supply and installation

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Our own installation crew

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Free in-home estimate

Why Choose Fiberglass Windows for Ontario Homes?


Window Experts supplies and installs Inline fiberglass windows in Ontario homes that face deep winter cold and humid summer heat. Although your glass package and our installation also shape a window’s overall performance, the frame material deserves a close look before you choose. Here is what a fiberglass frame offers.

  • Frame stability: Fiberglass expands and contracts less than many common frame materials, helping your frame hold its shape through seasonal swings.
  • Low heat transfer: Fiberglass conducts very little heat, which keeps your insulation performance steady across the glazing and the rest of the window assembly.
  • Strength and sightlines: Engineered profiles can support slimmer frames and larger glazed areas in suitable configurations.
  • Routine care: Factory finishes offer colour choices. Windows still need regular cleaning and attention to their moving parts.
Ontario home exterior with new replacement windows and front steps
Stone wall with modern black-framed windows

Inline Fiberglass Windows We Supply and Install


Inline manufactures the fiberglass windows, while we guide your product selection, replace your existing windows and install the new ones. Inline forms its frames through pultrusion, which pulls resin-coated glass fibres through a heated die to shape each profile. Those profiles become the frames of your windows.

Once we have measured your opening and discussed how you use the room, we review styles, finishes, and glass options with you and confirm the configuration before ordering. Browse the full range on Inline’s website or in the brochures below, then bring your questions to your free estimate.

Fiberglass vs Vinyl Windows: Which Is Right for Your Home?


Fiberglass and vinyl can both suit your replacement, and the right choice depends on priorities such as larger openings, finish choices and how long you plan to stay.

ConsiderationFiberglassVinyl
Frame stabilityMoves less with temperatureReview the selected profile
Strength and sightlinesNarrow profiles in suitable designsCompare the available glass area
Heat transferLow conductivityAssess complete window performance
Maintenance and finishesFactory finish optionsCheck product care and colour options

Our vinyl replacement windows also offer options for your project. Ask us to compare specific configurations and written estimates so your decision reflects your priorities and budget.

Fiberglass Window Styles, Colours and Glass Options


Inline’s range includes standard and custom colours, with different interior and exterior finishes on applicable products. We review Low E glass and grille options, and confirm the available glazing packages for your selected windows before ordering.

Casement window with an arched transom on a brick exterior

Casement and awning windows

Pair these with coordinated fixed windows to bring ventilation exactly where you need it. Inline’s designs include profiles that align the appearance of your adjoining units.
Horizontal sliding window and hung window styles

Hung and sliding windows

Choose from single-hung, double-hung, and horizontal sliding configurations for your home, with glass and grille options to match.
Black-framed window with white interior trim

Tilt-and-turn windows

The sash tilts inward from the top for ventilation or swings fully inward for cleaning and a wider opening. Leave room inside for the swing.
Large black-framed living room window with white interior trim

Fixed and contemporary windows

Fixed windows bring in light and views without opening, and narrow, uniform sightlines let larger glass areas stand out where the system suits your opening.
Black-framed bay window interior shown during installation

Bay, bow, and custom configurations

Bay and bow windows combine casements and hung or fixed units to create gentle curves or a box bay. Ask us what is currently available.

What Affects the Cost of Fiberglass Windows?


These factors shape your fiberglass window estimate:

  • Window count and dimensionsmore windows and larger openings mean more glass, framing and labour.
  • Style and operationfixed windows have no moving parts, while operable windows add hardware.
  • Colour and finishcustom colours or different interior and exterior colours can add cost.
  • Glass and grillestriple glazing and grille patterns can raise the price.
  • Existing opening and trimrot, water damage or damaged trim may need repair before installation.
  • Accessupper-storey or hard-to-reach windows need extra equipment.

A written estimate follows your free in-home assessment. Our pricing guide covers standard-window ranges, and Inline fiberglass windows are quoted separately.

Our Fiberglass Window Replacement and Installation Process


Your fiberglass window replacement starts with a free in-home visit and finishes with a walkthrough of the completed work.

01

In-Home Consultation and Measurements

We inspect your existing windows, measure each opening and discuss what you want to improve, including any drafts, leaks or operating problems.

02

Product Selection and Written Estimate

We review styles, finishes and glazing with you, then provide a written estimate listing the selected products and installation scope.

03

Ordering and Installation

Once you approve the selections, we order your windows. Our crew removes the existing units, fits the replacements, and insulates and seals around the frames.

04

Cleanup and Final Inspection

We clean the work area, check that each window operates properly and walk through the finished installation with you before the job is complete.

Why Choose The Window Experts for Fiberglass Windows?


  • One company handling your project: We manage product supply and installation together, so you have one company to contact for your replacement.
  • Hands-on installation experience: Our installers bring more than 15 years of hands-on experience. Our full-time crew installs your windows.
  • An estimate before approval: Your consultation covers products and installation needs. Review the written estimate and ask questions before approving the work.
  • Financing available: Ask about current financing terms when you book your estimate.
Window Experts installer working on a home exterior window

Fiberglass Window Projects

Fiberglass Window Replacement Across the GTA and Southern Ontario


We serve York Region, the GTA and Southern Ontario communities. Contact us to confirm coverage for your project. Tell us where you’re located and how many windows you plan to replace when you request your consultation.

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Fiberglass Windows FAQs

Are fiberglass windows better than vinyl?

Neither is better for every home. Fiberglass frames move less with temperature and can allow slimmer sightlines, while vinyl needs no painting. We compare both options against your priorities and budget.

How much do fiberglass windows cost?

We quote your fiberglass windows after measuring your openings. Window count, size, style, finish, glass and installation requirements affect the total, and a written estimate follows your free in-home consultation.

Who makes your fiberglass windows?

Inline Fiberglass manufactures the windows. We help you choose the configuration for your home, then handle the replacement and installation with our own crew.

Do fiberglass windows hold up in Ontario winters?

Your fiberglass frame expands and contracts very little through Ontario’s temperature swings, and it conducts very little heat. How your windows perform through winter also depends on the complete window, including the glazing, weatherseals and installation.

Are fiberglass windows worth the extra cost?

Compare written estimates first. If fiberglass costs more for your selected configuration, weigh that difference against the frame stability, sightlines and finishes you want. Material alone does not determine value.

Will you install windows I bought elsewhere?

No. We supply and install our own windows. We don’t install windows purchased elsewhere, so every project goes through one company from product to finished installation.

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Get a Free Estimate for Fiberglass Windows

Tell us about your replacement project. We’ll measure your openings, review window options and provide a written estimate so you can decide on the products and installation for your home.