Home Renovation Contractor in Oshawa & Durham Region
One contractor for the whole job — main-floor and full-home renovations run as a single coordinated build. One team, one contract, one point of contact, from the first site meeting to the day we hand back the keys.
Back to Residential ServicesA Renovation Contractor You Can Actually Trust
When you hire a home renovation contractor in Oshawa, you're trusting one person to run the whole job — the trades, the schedule, the budget, and the standard everything is held to. That's exactly what Cornerstone Construction does. We're a licensed, insured renovation contractor serving Oshawa and Durham Region, and we run every project as one coordinated build: one team, one contract, one point of contact.
Whether it's a single main floor or a full home taken back to the studs, the standard never changes — Level 4 drywall, daily cleanup, a locked price, and a 5-year workmanship warranty backed by a full Owner's Manual at handover. No subcontractor runaround, no surprise invoices. Just renovations done right, the first time.
Recent Work
Renovations Across Durham Region
Real homes, rebuilt to one standard — main floors, whole homes, and full condos across Oshawa, Whitby, Bowmanville, and Courtice.
Why Durham Region Homeowners Choose Us
We Show Up
Mike Brock or a named supervisor is on your job every day. You always know who's in charge and how to reach them.
One Contract
One team manages every trade and every stage. No subcontractor runaround, no finger-pointing — one point of contact start to finish.
We Lock Your Price
Your quote is your price. No surprise invoices, and no change orders without your written approval.
We Back Our Work
Every renovation carries our 5-year workmanship warranty and a full Owner's Manual at handover.
"Mike was the most professional and punctual contractor I have ever worked with. He understood how to bring my 10-year vision into reality. If it is not straight then it is not correct. He will make sure that it is. He will now be the only contractor to touch any part of my house."
Choosing a Contractor in Oshawa
Questions to Ask Before You Hire
Hiring the right home renovation contractor is the most important decision you make. Here is what Durham Region homeowners ask us most — and the honest answers.
How do I choose a reliable home renovation contractor in Oshawa?
Start with proof, not promises. Make sure the contractor is a licensed Ontario corporation, carries liability insurance, and is registered with WSIB. Ask to see real local projects and a written warranty. The clearest sign of a contractor you can trust is simple: they put the price, the schedule, and the warranty in writing before any work begins. We do all of that on every job.
Is Cornerstone Construction licensed and insured?
Yes. Cornerstone is a fully licensed and insured Ontario corporation, registered with WSIB, with 35+ years of hands-on experience and 300+ completed projects. You are protected on every job, and we provide proof before we start work.
How much does a home renovation cost in Durham Region?
Every home is different, so the honest answer depends on the size of the project and the finishes you choose. What does not change is how we price it. You get a fixed price in writing, and our Price Lock Guarantee means that number does not move unless you change the scope. No surprise bills at the end.
How do you keep my renovation on time and on budget?
Two guarantees, both in writing. Our Price Lock Guarantee holds your price steady from day one. Our $300-per-day on-time guarantee puts our own money on the line if we miss the agreed finish date. You also follow progress in real time through your private project portal, so you always know where things stand.
What is it like to live through a renovation with Cornerstone?
Cleaner and calmer than most people expect. We seal off the work area with HEPA containment from day one, vacuum the site daily, and never leave your home a mess. You get one point of contact and full visibility, so you always know what is happening and what comes next.
What makes Cornerstone different from other Durham Region contractors?
35+ years of experience and 300+ completed projects, backed by guarantees most contractors will not put in writing: a locked price, a $300-per-day on-time guarantee, a real-time project portal, daily cleanup, and a 5-year workmanship warranty. We treat your home with commercial-grade discipline. We Listen, We Build, We Deliver.
Ready to Start Your Renovation?
Book a free Project Diagnostic and get a clear, fixed-price plan from a contractor who runs the whole job — start to finish, with no surprises.
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