Cornerstone Construction

Cornerstone Construction Renovating shouldn't feel like a gamble. Kitchens, bathrooms & basements — Durham Region & GTA. We are located in Oshawa Ontario.

Cornerstone Construction's mission is to provide the highest-quality workmanship possible. We succeed at this because of the integrity of our subcontractors and staff, our commitment to a solid work ethic, and our passion for staying current with the newest innovations of our industry, with consideration for the environment. We have a full millwork shop providing custom millwork.

Q&A TUESDAY"I'm listing my house in a few months. What actually needs fixing first?"Good question — and the honest answe...
09/01/2026

Q&A TUESDAY

"I'm listing my house in a few months. What actually needs fixing first?"

Good question — and the honest answer surprises people.

✔️ Clean, declutter, fresh paint, fix anything broken or leaking
✔️ Skip the full kitchen remodel, the addition, anything built around YOUR taste
✔️ Kitchens and bathrooms usually depend on the room — that's what a walkthrough is for

Most sellers overspend on the wrong thing and underspend on the one thing that actually costs them the sale.

What would you ask first?

— Mike

Before you spend a dollar getting your house ready to sell, ask one question:Would a buyer actually notice this — and wo...
08/31/2026

Before you spend a dollar getting your house ready to sell, ask one question:

Would a buyer actually notice this — and would it change what they're willing to pay?

That's the whole test.

We just published the full walkthrough: what to fix, what to skip, and the real ROI numbers for kitchens, bathrooms, and basements before you list. 🏠

Link in the comments. 👇

After 35 years of doing this, here's a detail nobody asks about until it matters.When we hand you the keys, you get more...
08/31/2026

After 35 years of doing this, here's a detail nobody asks about until it matters.

When we hand you the keys, you get more than a finished room. You get The Cornerstone Care Guide — every spec, every warranty, every care guide, all in one place. 📖

Because six months from now, when you're touching up a wall or the dishwasher needs service, you shouldn't have to guess, dig through old texts, or call around trying to remember what we used.

That's not a nice-to-have. That's just how I think a job should end.

— Mike

DESIGN DEEP DIVEMost people think an addition is just building a box onto the house.It's not. A real addition means tyin...
08/26/2026

DESIGN DEEP DIVE

Most people think an addition is just building a box onto the house.

It's not. A real addition means tying a new foundation into the old one, matching structural loads, extending electrical and HVAC, and meeting current code on a house that was built to an older one.

Skip any of that and you don't have an addition — you have a problem waiting for the next owner to find.

We wrote the full breakdown on what a garage conversion and an addition each actually involve — permits, structure, resale value, and what most people wrongly assume they can skip.

Link in the comments. 👇

— Mike

✨ Inspiration SundayThe best rooms I've ever built were never the fanciest ones.They were the ones that fit.The island a...
08/23/2026

✨ Inspiration Sunday

The best rooms I've ever built were never the fanciest ones.

They were the ones that fit.

The island at the exact height she likes to roll dough. The drawer that finally landed where he actually reaches for it. A bench by the door — because that's where the backpacks pile up anyway.

None of that comes out of a catalogue.

It comes from someone actually asking how you live in your home… and then building around the answer.

That's the part you feel every single morning. Not "we renovated the kitchen." But — this room finally fits us.

The finishes are what you see. The fit is what you feel.

Here's to a home that fits the people in it. 🏡

— Mike

🛠️ Weekend tip: start your reno "yes / no / maybe" list before you call a single contractor.Grab a piece of paper. Three...
08/22/2026

🛠️ Weekend tip: start your reno "yes / no / maybe" list before you call a single contractor.

Grab a piece of paper. Three columns.

✅ YES — the stuff you know you want. New cabinets. Move the island. Pot lights.

❌ NO — the stuff you've already ruled out. "We're keeping the flooring." "Not touching the layout."

🤔 MAYBE — the wish-list items you'd do if the budget allows. Heated floors. That wall you keep staring at.

That's it. Fifteen minutes at the kitchen table.

Here's why it's worth doing 👇

When you sit down with a contractor and you already know your yes / no / maybe, two things happen:

You stop paying for quotes on stuff you didn't actually want. And your "maybe" list becomes the honest conversation — "here's what I'd add if the numbers work" — instead of a surprise halfway through.

The homeowners who walk in with this list get better quotes, faster. Every time.

Decide up front. Even a messy list beats a blank page. ✔️

— Mike

The internet has homeowners scared of all the wrong things. 🚩I read these contractor "red flag" lists and half of them a...
08/21/2026

The internet has homeowners scared of all the wrong things. 🚩

I read these contractor "red flag" lists and half of them are nonsense that'll actually push you AWAY from the good guys.

Let me clear a few up.

"He asked for a deposit — RUN."

No. A reasonable deposit tied to materials and a signed contract is normal. I've got to order your cabinets, your tile, your fixtures — that money buys YOUR stuff. A contractor who asks for nothing up front either isn't buying quality materials or isn't going to last. The deposit was never the danger.

"He asked a hundred questions — he must not know what he's doing."

Backwards. The guy who quotes your kitchen in five minutes is the one who's going to surprise you. Questions mean he's actually thinking about YOUR job.

"He's not the cheapest — he's overcharging."

The lowest bid is almost never the deal. It's usually the one with the most left out — and you pay for it later in change orders. Cheapest up front and cheapest at the end are rarely the same contractor.

Now here's what an actual red flag looks like 👇

🚩 Wants a big chunk of cash up front with nothing on paper.
🚩 "I need a payment" — but nothing's finished.
🚩 Won't put the scope in writing.
🚩 Gets defensive when you ask fair questions — who has a key, how you protect the house, who's actually on site.

See the difference?

The deposit was never the danger. The guy who won't put anything on paper is.

Stop worrying about the wrong flags. Learn the real ones. 👊

— Mike

📋 Want the actual checklist I'd use? Comment "CHECKLIST" and I'll send it to you.

⏪ 35 years on job sites. Here's the pattern I can't unsee.The homeowners who got burned on a renovation? Almost none of ...
08/20/2026

⏪ 35 years on job sites. Here's the pattern I can't unsee.

The homeowners who got burned on a renovation? Almost none of them were unlucky.

They just didn't know what to ask before they signed. 🖊️

I've been called into a lot of homes to fix a job that went sideways. And it's almost always the same story — nobody was a villain. The homeowner trusted a handshake and a number, and the contractor filled in the blanks his own way.

By the time I'm standing there, the drywall's up, the budget's blown, and the questions that would've caught it were never asked.

Early on, that used to make me angry at the other guy.

Now I know better. The homeowner was set up to lose the moment they didn't know what to ask.

So a while back I sat down and wrote out the exact questions I'd ask before I let ANYONE renovate my own house.

Not contractor secrets. Just the stuff that separates a smooth job from a nightmare.

That's the whole reason the Contractor Hiring Guide exists. 📋

Decide up front. Ask the hard questions before demo day — not after.

📌 Grab the guide in the comments. Print it. Bring it to every quote.

— Mike

🔨 Let's clear up a myth about change orders.A lot of homeowners think contractors LOVE them — like it's how we pad the b...
08/19/2026

🔨 Let's clear up a myth about change orders.

A lot of homeowners think contractors LOVE them — like it's how we pad the bill.

Honest truth? I hate them.

Here's what a change order actually looks like on my end 👇

▪️ The work stops.
▪️ I re-price the labour and materials.
▪️ I rebuild the schedule — which pushes back everything behind it.
▪️ I call the subs and try to fit you back into their calendar.
▪️ And sometimes we tear out finished work to make the change happen.

Every one of those steps is a chance for something to get missed — or collide with work that's already in the wall.

Move a sink after the plumbing's roughed in, and you're not making one change. You're undoing three. 💸

So no — a change order isn't a payday. It's a disruption, a risk, and a headache. For you AND for me.

Here's the part that matters 👇

This is EXACTLY why a good contractor asks you a hundred questions before demo day.

Every decision we lock in up front is a change order that never has to happen.

The questions aren't us being difficult. They're us protecting your budget and your schedule before there's a wall in the way.

Decide it up front. Cheaper, faster, calmer — every time.

— Mike

❓ "Why do you spend so long on the scope before you'll even give me a price?"Got asked this last week. Fair question. He...
08/18/2026

❓ "Why do you spend so long on the scope before you'll even give me a price?"

Got asked this last week. Fair question. Here's my honest answer 👇

A scope of work is just a written list of everything the job includes. Every task. Every material. Who supplies what. What's NOT included.

Sounds boring. It's actually the most important document in your whole renovation.

Here's what it does for you 👇

✔️ Makes your quotes comparable. Without one, three contractors price three different jobs — and you're comparing apples to oranges.

✔️ Kills the surprises. The stuff that blows a budget mid-project is almost always the stuff nobody wrote down.

✔️ Protects you. If it's on the scope, it's in the price. If it's not, that's a conversation you want NOW — not after the wall's already open.

The contractor who rushes past the scope to hand you a fast number isn't doing you a favour.

He's just moving the hard questions to the most expensive place to answer them: mid-build. 💸

Decide it up front. Put it on paper. Then everyone's finally building the same job.

📌 Full breakdown in the comments.

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Oshawa, ON

Opening Hours

Monday 8am - 5pm
Tuesday 8am - 5pm
Wednesday 8am - 5pm
Thursday 8am - 5pm
Friday 8am - 4pm

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