General contracting Durham Region
Durham Region General Contractors

Everything Under Your Roof. One Contractor. One Contract.

Walls, floors, ceilings, doors, trim, electrical, plumbing, drywall, painting, and structural work — managed by one team, fixed price, from start to final handover.

Back to Residential Services
35+Years Experience
100%Turnkey Service
500+Projects Completed
5yrWorkmanship Warranty
One Point of Contact

We Handle Everything Under Your Roof — So You Do Not Have To

Most homeowners have a list of things that need to get done. A wall that needs to come out. A bathroom that needs updating. Floors that need replacing throughout. A ceiling that needs to come down. They call three different contractors, get three different timelines, and spend six months coordinating people who do not talk to each other.

At Cornerstone, you make one call. We handle everything under your roof — walls, floors, ceilings, doors, trim, electrical, plumbing, drywall, painting, and structural work — under one contract, with one fixed price, and one person accountable for all of it.

  • Full Scope Assessment

    Before a single number is discussed, we walk your property and identify everything that needs to happen. Then we build a complete scope and a fixed price around that.

  • Trade Coordination

    Framer, electrician, plumber, drywaller, tile setter, painter — we manage every trade on your project from scheduling to payment. One point of contact.

  • Permit Management

    We pull and manage every permit your project requires. You do not deal with the municipality. We do.

  • Daily Site Updates

    You always know what happened today and what is next. We update your client portal every evening so you are never left wondering.

  • White Glove Handover

    Final walkthrough, Owner's Manual, and full warranty documentation at handover. You know exactly what was done and how to maintain it.

"One team. One contract. One call."

Start Your Home Diagnostic
Mike Brock reviewing project scope Durham Region
Scope of Work

Everything Done Under One Roof

"From permits to final punch list — one team, one contract, no surprises. All work performed by licensed trades."

Full scope assessment and fixed price proposal before we start
All demolition and structural work — walls, beams, and headers
Electrical — panel upgrades, pot lights, outlets, and new circuits, all completed by a licensed electrician to ESA standards.
Plumbing — new rough-in, fixture replacements, and pipe work
Drywall — Level 4 finish throughout
Flooring, tile, painting, and trim
All permits pulled and managed by Cornerstone
Final clean, punch list, and Owner's Manual at handover
What We Build

No Project Is Too Complex

Multi-room, multi-trade, or complex structural work — we manage every scope with the same fixed price commitment and white glove standard.

Multi-Room Renovations

Kitchen, bathroom, and main floor renovated under one contract. One mobilisation. One timeline. One price. More efficient and less disruptive than hiring separate contractors for each space.

Multi-room renovation kitchen and living room Durham Region

Additions & Structural Work

Room additions, garage conversions, and structural modifications managed from permit to final inspection. Complex scopes handled with the same discipline as our standard renovations.

Structural wall removal beam installation Durham Region

Insurance Restoration

Full project management for insurance-related repairs — water damage, fire damage, and mould remediation. We work with your adjuster and handle everything from demo to rebuild.

Insurance restoration water damage rebuild Durham Region

Pre-Sale Property Preparation

Pre-sale renovation and staging prep for homeowners and realtors. Targeted improvements that maximise listing value on a defined budget and timeline.

Pre-sale renovation Durham Region
Everything Under Your Roof

One Contractor. Every Trade.

If it is inside your home, we handle it. Here is what each service costs in Durham Region — real numbers with no hidden markups.

Wall Removal

Standard — Non-load-bearing$500 – $2,500
Premium — Load-bearing drop beam$7,000 – $15,000
Custom — Flush beam seamless ceiling$12,000 – $20,000+

Load-bearing or non-load-bearing — we assess, engineer, permit, and execute. Every structural wall removal includes a P.Eng. stamp before permit submission.

Wall removal open concept Durham Region

Demolition

Standard — Bathroom demo$600 – $2,000
Premium — Kitchen demo$1,500 – $3,000
Custom — Full gut per room$2,000 – $5,000+

HEPA containment from day one. Negative air scrubbing machines and sealed dust barriers before the first swing. Hazardous material testing on pre-1990 homes included in assessment.

Clean demolition site HEPA containment

Flooring

Standard — LVP and LVT$5 – $12 per sq ft
Premium — Engineered hardwood and porcelain$10 – $25 per sq ft
Custom — Solid hardwood and large-format slab$14 – $100+ per sq ft

We install LVP, LVT, porcelain, ceramic, engineered hardwood, and solid hardwood. Every floor starts with a substrate inspection — flat to within 1/8 inch over 10 feet before any flooring goes down.

Hardwood and tile flooring installation

Painting

Standard — Priming$1 – $2 per sq ft
Premium — Walls and trim$3 – $5 per sq ft
Custom — Specialty finish$6 – $7+ per sq ft

Two coats minimum. Benjamin Moore Regal Select or Sherwin-Williams Emerald. Surfaces repaired, caulked, and primed before paint touches the wall.

Professional painting Durham Region

Popcorn Ceiling Removal

Standard — Unpainted$2 – $3 per sq ft
Premium — Painted$4 – $6 per sq ft
Custom — Asbestos abatement$7 – $15+ per sq ft

Festool Planex long-reach sander with CT HEPA extractor. Dust captured at the point of cut — 99% of debris never touches your air. Level 5 smooth finish available.

Smooth Level 5 ceiling finish

Drywall

Standard — Hang and tape$1.80 – $2.50 per sq ft
Premium — Level 4 finish$2.50 – $3.50 per sq ft
Custom — Level 5 and soundproofing$3.50 – $5+ per sq ft

Level 4 drywall is our baseline — not Level 2. Fire-rated Type X for legal suite assemblies. Resilient channels and QuietRock available for sound control between rooms.

Level 4 drywall finish Durham Region

Stairs

Standard — Sand and refinish$50 – $90 per step
Premium — Solid hardwood recap$120 – $300 per step
Custom — Full staircase rebuild$10,000+ total

Sand and refinish existing treads or install solid oak and maple overlays over existing sub-steps. Black metal balusters and matching risers finished to your main floor standard.

Stair recapping oak treads black balusters

Interior Doors

Standard — Slab replacement labour$100 – $150
Premium — Pre-hung installed$250 – $1,500
Custom — French pocket double installed$1,000 – $2,500+

Slab replacement, pre-hung installation, or full French and pocket door systems. Frames plumbed and shimmed square. Matching casing installed and finished to your trim standard.

Interior door installation with casing

Carpentry & Trim

Standard — Baseboard and casing$4 – $10 per linear ft
Premium — Crown moulding$4 – $23 per linear ft
Custom — Custom built-ins$3,000 – $15,000+

Baseboard, casing, crown moulding, and custom built-ins. Precision mitre cuts and hand-coped inside corners. Solid hardwood or moisture-resistant MDF depending on location.

Custom built-ins crown moulding Durham Region

Structural Work

Standard — Drop beam$7,000 – $15,000
Premium — Flush beam$12,000 – $20,000
Custom — Full addition and complex structural$20,000 – $50,000+

Beam installation, load-bearing wall removal, header work, and point load transfers. Every structural modification requires a P.Eng. stamp before permit submission. We coordinate the engineer.

Structural beam installation Durham Region

Ranges reflect Durham Region market pricing as of 2025. Final investment confirmed in your written proposal — price locked before work begins.

Wall Removal — What It Really Involves

The Most Requested Service We Do. The Most Misunderstood.

Not every wall is the same. A non-load-bearing wall comes down in a day. A load-bearing wall requires an engineer, a permit, a beam, and a foundation assessment. Most contractors do not tell you this until they are already in your wall.

The Ontario Building Code requires a Professional Engineer (P.Eng.) to perform an on-site structural assessment and provide stamped drawings before any load-bearing wall is removed. This is not optional. Municipalities will not issue a building permit without it. Contractors who skip this step are not saving you time — they are creating a liability that voids your insurance and exposes your home to structural risk.

At Cornerstone, we assess every wall before we quote it. We identify the load path, coordinate the engineer, pull the permit, and execute the removal under inspection. You get a finished open space — and a permit history that protects your home on resale.

Non-Structural

Non-Load-Bearing Wall

Cost range $500 – $2,500
  • No structural engineer required
  • No building permit for simple partition walls
  • Electrical and plumbing relocation may be needed
  • Demo, patch, paint, and finish included
  • One day to one week depending on utilities

Fastest and lowest cost — but only if the wall is confirmed non-structural.

Load-Bearing

Load-Bearing — Drop Beam

Cost range $7,000 – $15,000
  • P.Eng. structural assessment required
  • Building permit required before work starts
  • Temporary shoring walls built during demo
  • LVL or steel beam installed below ceiling joists
  • Beam wrapped in drywall or decorative cladding

Beam is visible but can be designed as a feature. Faster than flush beam installation.

Premium Finish

Load-Bearing — Flush Beam

Cost range $12,000 – $20,000+
  • P.Eng. structural assessment required
  • Building permit required before work starts
  • Ceiling joists cut and reconfigured around beam
  • Beam recessed into ceiling cavity — fully hidden
  • Result is completely flat uninterrupted ceiling

The premium option. Ceiling looks like the wall was never there.

Engineer Specifies

LVL Beam vs Steel Beam

Decision guide Engineer selects
  • LVL: $3–$12 per ft material — moderate spans
  • Steel I-Beam: $6–$18 per ft — long spans
  • Steel is slimmer — better for tight ceiling depth
  • LVL is lighter — simpler installation
  • Engineer selects based on span and load path

We coordinate the engineer assessment as part of your project. You do not make this decision alone.

Durham Region Permit Fees for Structural Work

Oshawa structural alterations start at $155 flat fee. Whitby bills at $10.47 per square metre minimum $300. Ajax uses a $9.68–$14.22 multiplier minimum $329. Pickering runs $15.40 per square metre minimum $165. Expect 2–6 weeks for permit processing depending on municipality workload. Cornerstone manages the entire permit application — you do not make a single call to the city.

Dustless Popcorn Ceiling & Drywall

We Collect the Mess at the Point of Cut — Before It Hits Your Air

Cheap contractors scrape popcorn ceilings dry and let toxic particles rain onto your floors. We treat every ceiling removal as an engineered dust-containment project using the industry's most advanced tool stack.

Direct-Source HEPA Extraction

We use Festool Planex long-reach sanders with fully enclosed articulating heads hooked directly to Festool CT HEPA extractors. The dust is captured at the exact second it is sanded off the ceiling. 99% of the debris never touches your room's air.

Active Air Management

Even with direct-source sanding we do not take chances. This system runs in tandem with our mandatory Negative Pressure Zones — commercial air scrubbers filtering the ambient room air continuously throughout the entire project.

Flawless Level 5 Finish

Our specialized orbital sanding does not gouge your ceiling like primitive hand-scraping tools do. It cleanly removes the texture while perfectly prepping the gypsum board for a smooth, modern, paint-ready Level 5 finish.

Festool Planex dustless ceiling sanding Durham Region

Popcorn Ceiling Removal Calculator

Select ceiling type, adjust square footage, choose finish level, and add optional scopes to estimate your investment.

Ceiling Type
Ceiling square footage 800 sq ft
100 sq ft3,000 sq ft
Finish level
Optional add-ons 0 selected
Homes built before 1990 in Durham Region must be tested for asbestos before any ceiling texture is disturbed. Cornerstone coordinates mandatory testing as part of your project diagnostic.

Estimated investment range

$1,600 – $2,400

Ranges reflect Durham Region market pricing as of 2025. Final investment confirmed in your written proposal — price locked before work begins.

Start Your Home Diagnostic
The Cornerstone Standard

Your Home Is Protected From Day One

Complex projects mean more trades, more days, and more disruption potential. Our site protection protocol is designed to keep your home clean, safe, and livable regardless of how long the project runs.

Floor Armour

Guardia Pro applied to all hardwood, tile, and stone surfaces in all transit paths. HEPA vacuumed first. Self-adhesive, breathable, and waterproof. Protects every surface trades walk over every day of the project.

Floor protection Guardia Pro job site

Sealed Dust Containment

Floor-to-ceiling ZipWall barriers at every entry point. Heavy-duty zipper doors for crew access. Tuck tape sealed at every seam. Smoke detector dust covers installed. Your living space stays completely clean throughout the build.

ZipWall dust containment barrier job site

HVAC Protection

MERV 5 filter pads installed over every supply and return vent in the work zone. Prevents drywall dust and debris from entering your duct system and circulating through the rest of the house.

HVAC vent filter protection

Utility Safing-Off

SharkBite Max brass push-to-connect fittings for clean water isolation. Full LOTO Lockout Tagout electrical protocol before any panel or circuit work begins. No live work. No shortcuts. Ever.

SharkBite utility isolation job site

Daily Site Reset

Every day before we leave, the last 30 minutes of our shift is dedicated to cleanup. Tools away. Debris removed. Transit paths cleared. Your home put back in order every single night regardless of how long the project runs.

Clean job site end of day daily reset

Negative Pressure Zone

Hospital-grade HEPA air scrubber running continuously in the work zone. Creates negative pressure so airborne particles move toward the filter — not toward your living space. Running from day one to final cleanup.

HEPA air scrubber running on job site

"This is not an add-on. It is standard on every Cornerstone project regardless of scope or budget."

Common Questions

General Contracting Questions

Real answers for Durham Region homeowners who are not sure where to start.

What is the difference between a general contractor and a subcontractor?

A general contractor like Cornerstone manages the entire project — scheduling, permits, trades, and budget. Subcontractors are the individual trades we hire and manage on your behalf. You have one point of contact. We handle everything else. You never chase a plumber or electrician directly.

Do you handle projects of all sizes?

Yes. We manage projects from focused single-trade repairs starting at $20,000 to full home renovations and additions exceeding $300,000. Every project gets the same white glove service, the same fixed price commitment, and the same $300 per day on-time penalty clause.

Can you coordinate multiple trades at the same time?

Yes. Managing multiple trades simultaneously is the core of what a general contractor does. We schedule, coordinate, and supervise every trade on your project so you do not have to. Framer, electrician, plumber, drywaller, tile setter, and painter — all managed by us.

Do you pull all the permits?

Yes. We pull and manage every permit your project requires — building, electrical, plumbing, and structural. You do not deal with the municipality. We handle the application, the inspections, and the final sign-off.

What is included in your general contracting quote?

Everything. Labour, materials, permits, project management, daily cleanup, and final handover with an Owner's Manual. The number we quote is the number you pay unless you change the scope in writing. No surprise invoices. Ever.

Do you work across Durham Region?

Yes. We serve Oshawa, Whitby, Bowmanville, Ajax, Pickering, Newcastle, Clarington, Scarborough, Stouffville, and Peterborough. Most of our projects are within 45 minutes of our Oshawa base.

General contracting finished project Durham Region
Ready to Build

Not Sure Where to Start?

Book your free project diagnostic. We walk your property, assess the full scope, and give you a fixed price before we start — whether it is one room or the whole house.