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About Clera Windows + Doors

Clera Windows + Doors is one of the leading window and door manufacturers in Ontario.


Years of Family-Owned Experience


Happy Customers


Consultant Locations right here, in Ontario

Clera's Story

Rebranded To FM Windows & Doors - Clera Windows + Doors


Rebranded to FM Windows & Doors

First Generation Of Vinyl Windows - Clera Windows + Doors


First generation of vinyl windows are manufactured

Business model changed - Clera Windows + Doors


The company’s business model changed from dealer sales to contractors to direct-to-homeowner (including installation)

Started To Manufacture Sealed Glass - Clera Windows + Doors


Started to manufacture our sealed glass units in-house

Plant On Pennsylvania - Clera Windows + Doors


Built and occupied its current location, a modern 60,000-square-foot plant on Pennsylvania Avenue in Concord, Ontario

Rebranded To Clera Windows + Doors - Clera Windows + Doors


Rebranded to Clera Windows + Doors

Purchase Of Highly Automated Manufacturing Equipment - Clera Windows + Doors


Purchase of highly automated, state-of-the-art, sealed unit manufacturing equipment

Created Energy-Efficient Vinyl Windows - Clera Windows + Doors


Created the energy-efficient CLARITY line of vinyl windows used today

Company Began As An Aluminium Manufacturer - Clera Windows + Doors


Company began as an aluminum windows manufacturer

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Our Legacy as Ontario’s Premier Window + Door Company

Family-run since 1978, Clera Windows + Doors has earned its reputation as the most trusted provider for Ontario homeowners for nearly five decades.

Our customers mean everything to us, which is why we are a factory-to-homeowner operation. By managing the design and manufacturing of your replacement windows and doors—as well as the installation process—we can offer you high-quality products at factory-direct prices.

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Schedule A Free Consultation - Clera Windows + Doors

Reasons to Love
our Products

Clera Windows + Doors is a reputable vinyl window manufacturer in Ontario with a history of dependable and high-quality products. Our superior materials and cutting-edge technology ensure durability, energy efficiency, and style. We offer customizable styles and colors, as well as superior security features and noise reduction technology to provide the best possible product attributes for your home.

Our team manages every stage of your replacement project, from start to finish. We work closely with you to understand your specific needs and preferences, and use our extensive experience and knowledge to deliver a solution that exceeds your expectations. Trust Clera Windows + Doors for exceptional service and expertise for your home renovation needs.

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Energy Star Icon

Energy Star Approved

Effortless Operation Icon

Modern, Contemporary Design with more glass, and less frame

Better Home Security Icon

Better home security

Noise Reduction Icon

A quieter home; improved noise reduction from the outdoors

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No Maintenance Icon

No maintenance: vinyl windows are virtually maintenance-free

Pilkington Low-e Glass Technology Icon

Pilkington Low-E Glass Technology, engineered specifically for Canadian climates

Structural Integrity Icon

Wet-glazed frames and sashes on all windows; the ultimate in protection against water and wind infiltration, with added structural integrity

Improved Ventilation Icon

Triple-fin weatherstripping with built-in anti-microbial properties, meaning no mould and better air quality

Pure Virgin UPVC Icon

100% pure virgin UPVC, providing protection from fading

Exceptional Durability Icon

Stronger hardware and structural integrity thanks to integrating galvanized steel (allows for larger, more spectacular views!)

Clera Specializes in Manufacturing the Highest Quality Fenestration Products for:

Architects - Clera Windows + Doors


Customized manufacturing based on your needs!

At Clera, we control every part of the manufacturing process. From design to installation, we will work with you to create completely customized windows and doors for any project you need. Just let us know what you need and we’ve got you covered!

General Contractors - Clera Windows + Doors

General Contractors

Best quality windows, delivered on time!

A contractor’s job depends on the level of service they provide to their customers, and having the best quality building materials will get the job done right. Whether you’re overseeing the project of building a new home, remodelling an old one, or updating a specific room, Clera Windows + Doors can help.

Custom Home Builders - Clera Windows + Doors

Custom Home Builders

Lifetime warranty at unmatched prices!

Clera is the top choice for home builders looking to buy doors or windows in bulk. Tired of faulty builder-grade windows and doors? There’s no need to trim costs when you choose us. We offer top-tier custom products with a lifetime warranty policy on all vinyl hardware, components, and glass!

Homeowners - Clera Windows + Doors


One-Stop Solution for Superior Windows & Doors

Homeowners know Clera Windows + Doors is the best choice when it comes to purchasing, upgrading, or replacing their windows and doors. We offer top-tier premium products with a non-prorated lifetime warranty on all hardware, glass, and components.

Property Managers - Clera Windows + Doors

Property Managers

Durable ENERGY STAR® rated windows and doors!

Every landlord knows the importance of high-quality windows and doors. Energy-efficient fixtures pay for themselves in energy savings, keeping hundreds of dollars a year per rental property in your pocket! Clera’s windows and doors are all ENERGY STAR® approved, making them well worth the investment.

Interior Designers - Clera Windows + Doors

Interior Designers

A wide selection of windows and doors to choose from!

When designing a home, the windows and doors shouldn’t be an afterthought. The right window or door can completely transform the look and feel of any room, letting in the natural light we all crave. Whatever style or design you’re looking for, Clera can help you find the perfect solution.

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Why Choose Clera

Why take a chance with other window or door companies that purchase their products from another supplier, only to resell them to you for a higher cost?

Clera Windows + Doors is one of Canada’s largest, oldest, most dependable and reputable vinyl window manufacturers in Ontario. We fully manage and take care of your door and window replacement project from start to finish, ensuring every stage of your window or door project meets our lofty standards of craftsmanship.

Why are we Ontario’s most awarded window and door company?

The Clera Care Guarantee Logo

Over 45 Years of Experience

With over 45 years of experience, we have earned a reputation as one of Canada's leading window and door manufacturers and installers.

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Certified Technicians

You can trust our team of factory trained technicians to install your new windows perfectly—our A+ BBB rating is no accident!

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Serving Ontario With over 45 Branches

We have over 45 branches across Ontario, which means that we're always close by when you need us.

Non-prorated Lifetime Warranty Icon

Non-prorated Lifetime Warranty

Whenever anything goes wrong with your windows, we'll take care of it for you—no questions asked.

Energy Star Icon

ENERGY STAR® Certified

All of our windows meet Canada’s strict Energy Star standards. A Clera window is not only high-quality and durable, but also super energy-efficient.

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We Manufacture and
Install So You Save!

With Clera handling the entire manufacturing and installation process, we can offer you competitive prices allowing you to save money.


Homeowners know Clera Windows + Doors is the best choice when it comes to purchasing, upgrading, or replacing their windows and doors. We offer top-tier premium products with a non-prorated lifetime warranty on all hardware, glass, and components.

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Schedule A Free Consultation - Clera Windows + Doors

Over 45 Sales and Installation Offices Across Ontario

Find Your Nearest Consultant
Over 40 Sales And Installation Offices - Clera Windows + Doors

Save BIG with our FREE Factory Upgrades: Over $325 per window!

With Clera’s high-performance windows and doors, homeowners who upgrade with Clera are be eligible for free factory upgrades.

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Customized Windows & Doors In Alliston - Clera Windows + Doors

Steve Mastrorillo

1st Generation

Steve Mastrorillo, Founder - Clera Windows + Doors

Vito Mastrorillo

2nd Generation

Vito Mastrorillo, President - Clera Windows + Doors

Stefano Mastrorillo

Director of Strategy
3rd Generation

Stefano Mastrorillo, Director Of Strategy - Clera Windows + Doors

At Clera, Family Means Everything

Our story is deeply rooted in family values, beginning with two brothers, Steve and Frank Mastrorillo. They laid the groundwork for F & M Aluminum Manufacturing Company Ltd, crafting aluminum windows. Steve's eventual sole ownership marked a turning point, propelling us into a new era of innovation and dedication. 

With the entry of Vito Mastrorillo, Steve's eldest son, the company underwent a transformative change in its business model. Previously focused on sales to contractors and dealers, Vito recognized the opportunity to provide a more personalized experience to homeowners, fostering a stronger connection with the very people who bring life to the spaces we enhance.

Vito's ascension to President after Steve's retirement ensured continuity of our values. And now Vito’s son, Stefano Mastrorillo, joins us, bringing the same enduring commitment to excellence as his father and grandfather.

The Mastrorillo family's narrative weaves through Clera, inspiring us to craft windows and doors that frame not just spaces, but the cherished moments of your lives.

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