Name: Windows and Doors
Brand: Clera Windows + Doors
Rating: 4.7 (2557 reviews)

Our GTA Team

Our local Thornhill team has been serving Toronto and the GTA for over 45 years!

1-844-738-7936

Our Local Clera Branch Serves Thornhill

As the manufacturers and installers of all our windows and doors, we stand behind our work.

Clera Windows + Doors

Thornhill, Markham, Vaughan, Richmond Hill, and Surrounding Areas‍

Toll Free: 1-844-738-7936
Phone: 1-844-738-7936
Fax: 905-738-0586

Sales: sales@clerawindows.com
Service: service@clerawindows.com

Clera Windows + Doors

Toll Free: 1-905-738-1870
Phone: 1-905-738-1870
Fax: 905-738-0586

Sales: sales@clerawindows.com
Service: service@clerawindows.com

Get a Quote

Best Windows And Doors - Clera Windows + Doors

Replacement Windows & Doors Thornhill

Thornhill is a beautiful suburban neighbourhood in the Greater Toronto Area and home to over 110,000 residents. Located along the northern border of Toronto and split between the cities of Vaughan and Markham. What once was Ontario’s police village, an area that did not permit the development of a town, is now a thriving community for families, schools, local newspapers, and sports teams. Home to great restaurants, entertainment, places to shop, parks and recreation. Places like The Promenade mall and Conley Park South are the popular places for residents and visitors to enjoy during their time off.

For residents, being encompassed in all the great things Thornhill has to offer, you’ll want your home to reflect the beauty of it all with top quality windows and doors. Having beautiful windows and doors gives your home the utmost aesthetic appeal, creating a more vibrant and polished look for your visitors and community to admire. Fortunately, Clera Windows and Doors is an industry leader in both quality of work and customer service. Beyond instantly modernizing your home, new windows and doors can be a great remedy for soundproofing your home as well as provide better insulation to save you money and reduce greenhouse emissions in the winter.

As a family run company since 1978, you can be assured that we understand and appreciate the importance of any home renovation project to your family. We’re in the business of providing comfort and security for households across Canada, and we couldn’t be more grateful for all the homes and families that have entrusted us with such an important decision to improve their home’s functionality and security. All of our fenestration installation technicians are rated by the Canadian Standards Association and our products are all ENERGYSTAR rated as well, so you know our work can be trusted. We’ve also taken home the “Top Choice Award” and are so confident in our craftsmanship that we include a written, lifetime factory warranty on our products. What this means for you is that you won’t have to buy another pesky replacement part again!

Customized Windows & Doors In Alliston - Clera Windows + Doors

Invest In Your Home Today - Clera Windows + Doors

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?

Schedule a Free Consultation

Learn More

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.

Certified Technicians

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

Serving Ontario With over 40 Branches

We have over 40 branches across Ontario, which means that we're always close by when you need us.

Non-prorated Lifetime Warranty

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

ENERGY STAR® Certified

Our hung windows meet Canada's strict energy-efficiency standards. A window from Clera is not only high-quality and durable, but also energy-efficient.

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.

Energy Star Approved

Modern, Contemporary Design with more glass, and less frame

Better home security

A quieter home; improved noise reduction from the outdoors

No maintenance: vinyl windows are virtually maintenance-free

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

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

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

100% pure virgin UPVC, providing protection from fading

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

Hear What Clera
Customers Have to Say

With some of the highest ratings for customer satisfaction, it's clear why Clera is Ontario's most awarded window company!

9.2/10

on HomeStars

16x Homestars Winner

“I have nothing but good things to say about the services I have received from Clera. About 4 years ago I purchased a new front door from Clera. The salesperson was knowledgeable and understood what I was looking for...

Tammy Yazbeck

Muskoka

"Excellent! We have loved our dealings with Clera. Rod was amazing in listening and understanding the look we were trying to achieve and then suggesting products with the appropriate features...

Eric Tang

Ottawa

“We have received so many compliments on our doors. Mike and his crew (Mike and Anthony) are very friendly and professional...

Maria Novielli

Ontario

"We changed practically all the windows of our home and a sliding door and can't be more happy with the result.."

Roxalía Muñoz

Concord

"Both our sales rep, Greg, and installation team were courteous, skilled and acted professionally during the whole process. Will use Clera again for any future projects..."

Greg Buczynski

Concord

If you’re situated in the Thornhill, Markham, Vaughan, and Richmond Hill areas, you’ll find Clera Windows and Doors at 31 Hughson Drive in Markham. To book a free consultation or to get more information on new replacement windows and doors for your home, call Clera Windows and Doors at 1-844-738-7936 or follow these driving directions:

Continue onto the Don Valley Parkway N for 13.5 kilometers.
Continue onto ON-404 N for 8.7 kilometers.
Use the right 2 lanes to take exit 27 for Highway 7 toward Richmond Hill/Markham/ON-7 for 800 meters.
Use the right 2 lanes to turn right onto York Regional Rd 7 (signs for Markham/Highway 7 E) 900 meters
Turn left onto Woodbine Ave/York Regional Rd 8 (signs for Regional Road 8/Woodbine Avenue) 300 meters
Turn right onto Lunar Crescent 290 meters.
Turn left onto Hughson Drive, look for 31 Hughson Drive. The destination will be on the left.