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FeaturedVerifiedWindow Installers in Markham, Ontario

OPT Windows Ltd.

Featured in Markham Today 5.00 (19 reviews)(365) 899-0345

OPT Windows Ltd. designs, manufactures and installs thermally broken aluminum windows, doors and porch enclosures. Based in Markham, it serves Toronto and the GTA.

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Business Highlights
  • Its products are made in Ontario for Canadian weather.
  • Its manufacturing is factory direct.
  • One team handles design, manufacturing and installation.
  • Its products are custom built for every home.
Service Area

Toronto, Markham and the GTA.

Featured on ProsGrade. OPT Windows Ltd. is one of 9 window installers ProsGrade lists in Markham, Ontario.

Listing details

5 services listed, including Thermally broken aluminum windows, Porch enclosures and Sliding doors. Open Monday to Saturday. Rated 5.0 from 19 reviews.

  • Verified listing details
  • Service information
  • Customer review signals
  • Photo gallery
  • Public contact information
  • Published local profile

How This Business Compares

How OPT Windows Ltd. compares with the other 8 window installers on ProsGrade in Markham, using public Google ratings and review counts.

  • Ranks in the top quarter of the 9 Markham window installers on ProsGrade by Google rating and review volume.
  • Rated 5.0 on Google, at or above the 4.9 average of other Markham window installers on ProsGrade.
  • One of 6 Markham window installers on ProsGrade rated 4.7 or higher from at least 10 reviews.

Services Covered

5 services
  • Thermally broken aluminum windowsCasement, awning, tilt-and-turn and custom-shaped styles.
  • Porch enclosuresHelps reduce cold drafts and adds storage space.
  • Sliding doorsLift-and-slide systems with large glass panels.
  • Security screen doorsAluminum construction, 304 stainless steel mesh and multi-point locking.
  • Entry doorsVarious styles, glass options and finishes.

Reviews

What customers say

Customers praise Craig and his team as professional and helpful, and say the installed windows and doors feel sturdy. One customer appreciated the protective pads and careful cleanup; another found a replacement patio door sturdy and well insulated.

Customer Reviews

Amy Ho

Craig and his team are very nice and professional. They had all protective pads and vaccums handy, and clean your window and doors carefully after installation. The window and door looks sturdy and secure with great noise reduction. 100% recommend this team if you want someone who knows their products and reasonably priced items.
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Kristy Leung

Installed a new backyard secure screen door. Very well-made aluminium door frame with durable stainless steel mesh. It looks sturdy and feels secure. Thank you Craig and his team they’re very nice and helpful. 100% recommend to neighbours and friends!
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Austin Guan

Craig's team did a great custom job replacing old patio sliding door. The new one feels super sturdy and offers great insulation which you can feel right off the bat. 10/10 would recommend to friends!

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Frequently Asked Questions

How do OPT Windows' tilt-and-turn windows open?

They tilt for secure ventilation or swing open for maximum airflow and easy cleaning.

What glass is standard in OPT Windows' sliding doors?

Double tempered glass with argon is standard; triple glazing and Low-E glass are optional.

Can OPT Windows' awning windows stay open in light rain?

Their top-hinged design lets them remain partly open during light rain while keeping water outside.

What colours does OPT Windows offer for security screen doors?

Black, white, beige and custom colours are available.

Are OPT Windows' custom-shaped windows made to exact measurements?

They are custom-manufactured to fit exact dimensions.

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