Cornerstone Building Group
This score reflects 21 verified reviews, across 2 platforms, WSIB coverage confirmed.
How is this calculated?About Cornerstone Building Group
Cornerstone Building Group is a general contractor based in Mississauga that works on site and operates during weekdays. The company has completed stucco and exterior renovation work, offers clear initial quotes with transparent options, and maintains wheelchair-accessible parking and washroom facilities on-site with free parking available.
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What Customers Say
Top Strengths
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Ratings Across Platforms
Aggregated from independent sources. Only ProScore shows all.
Not found on 2 other platforms ProScore checks (BBB, Review platform C).
ProScore aggregates Google, the BBB and other major review platforms. Some sources are not named publicly.
Things to Know
Trusted Level
Scores in ProScore’s Trusted tier — strong, consistent signals across the sources ProScore checks.
Highly Rated
Consistently rated 4.8 stars across 21 Google reviews.
Rated on Multiple Platforms
Independently rated on 2 review platforms — ratings that agree across sources are harder to game.
WSIB Verified
Workplace Safety and Insurance Board coverage confirmed — you're protected.
What Reviews Highlight
Reviews mention: quality craftsmanship, professional service, quote changes and pricing concerns.
Google Review Breakdown
21 totalFeatured Review
Verified review from Google
We had the pleasure of working with Heiner from Cornerstone Building Group for a exterior renovation of our home, and we couldn’t be happier with the results. A few years ago, we saw some of his residential work in our neighborhood, and when it came time for our own project, we knew we wanted to reach out. From the start, Heiner was extremely friendly, polite, and professional. He took the time to listen to our ideas, provided a clear and fair quote, and always gave us options without ever pres
Other top rated general contractor in Mississauga
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