Every Project. Every Time.

The Cornerstone Certainty Stack

Eight guarantees that protect you from the first day to long after the last. This is how we turn "trust me" into something you can hold in writing — the promises behind "We Listen, We Build, We Deliver."

Start Your Project Diagnostic Call 1-888-404-7383

Most contractors make promises. We put ours in writing.

Anyone can say they're different. We decided to prove it — with eight specific, written guarantees that cover the things homeowners worry about most: the price, the timeline, the mess, the communication, and what happens after we're gone. Tap any guarantee below to see exactly how it works.

Price Lock Guarantee

Your price is locked before we start. No surprise bills. Ever.

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$300/Day On-Time Guarantee

Miss your completion date and we pay you $300 for every day we run late.

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HEPA Air Filtration

Hospital-grade air scrubbers and sealed dust walls keep your home clean throughout.

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Daily Cleanup

We reset the site every day before we leave, so your home stays livable.

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Real-Time Client Portal

Track progress, approvals, and documents anytime through your live project portal.

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5-Year Warranty

Every job is backed by a full 5-year workmanship warranty — five times the standard.

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Owner's Manual

At handover you get a complete manual — finishes, documents, warranty, and care guides.

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Fully Licensed & Insured

A fully licensed and insured Ontario corporation. WSIB compliant. Ask for proof anytime.

Certainty isn't a slogan. It's the whole system.

Eight guarantees, working together, so you always know where your project stands and what we stand behind. That's what makes a renovation with Cornerstone different — and it starts with one honest conversation about your project.

Start Your Project Diagnostic Call 1-888-404-7383

Durham Region's trusted renovation contractor. Led by Mike Brock since 2017. We Listen, We Build, We Deliver.

Service Areas

  • Oshawa, ON
  • Whitby, ON
  • Bowmanville, ON
  • Clarington, ON
  • Ajax, ON
  • Pickering, ON
  • Newcastle, ON
  • Scarborough, ON
  • Whitchurch-Stouffville, ON
  • Port Perry, ON
  • Peterborough, ON
  • Port Hope, ON
  • Cobourg, ON
  • Northumberland County, ON
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