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 ServicesWhen 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 an insured, WSIB-covered 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 is the same — Level 4 drywall, daily cleanup, a locked price, and a 5-year workmanship warranty. You also get a full Owner's Manual at handover. Changes to the scope are priced and approved by you in writing before the work happens. Just renovations done right.
Recent Work
Real homes, rebuilt to one standard — main floors, whole homes, and full condos across Oshawa, Whitby, Bowmanville, and Courtice.
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 team manages every trade and every stage. No subcontractor runaround, no finger-pointing — one point of contact start to finish.
Your quote is your price. No surprise invoices, and no change orders without your written approval.
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
Hiring the right home renovation contractor is a big decision. Here is what Durham Region homeowners ask us most — and the honest answers.
Start with proof, not promises. Make sure the contractor carries liability insurance, is registered with WSIB, and uses licensed trades for electrical and plumbing. Ask to see real local projects and a written warranty. A good 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.
Yes. Licensed where required, insured. We carry $5,000,000 liability insurance and current WSIB coverage, with 35+ years of hands-on experience and 300+ completed projects. Electrical and plumbing are done by licensed trades, and we pull permits wherever your job requires one. Ask for proof anytime.
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. Any change is priced and approved by you in writing before the work happens.
Two guarantees, both in writing. Our Price Lock Guarantee holds your price steady once you sign. On projects of $15,000+ that run about a month or longer, our $300/Day On-Time Guarantee credits you $300 for each day we miss the completion date for reasons within our control. You also follow progress in real time through your private project portal, so you know where things stand.
Cleaner and calmer than most people expect. We seal off the work area with sealed dust walls, run HEPA air scrubbers on heavy dust days, and clean up at the end of each day on site. You get one point of contact and full visibility, so you know what is happening and what comes next.
35+ years of experience and 300+ completed projects, backed by written guarantees: a locked price, an on-time guarantee on larger projects, 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.
Book a free Project Diagnostic and we'll talk through your project. After the site visit, you get a written price from a contractor who runs the whole job, start to finish.
View Full Portfolio ›
Durham Region's trusted renovation contractor. Led by Mike Brock since 2017. We Listen, We Build, We Deliver.
