Home Addition Contractors in Hamilton & Halton
- 5-Year Warranty
- Permits Handled
- 100% Built In-House
Is a Home Addition Cheaper Than Moving?
A home addition is new, permanent living space built onto your existing house, and it is one of the smartest ways to get the room your family needs without leaving the neighbourhood you love. Whether you are dreaming about a larger kitchen, a main floor family room, a second storey addition over a bungalow, a private in-law suite or secondary suite for aging parents, a bump-out addition to steal a few extra feet, or a garage conversion that turns dead space into a real room, a well designed home addition gives you more space and more function in the home you already own.
For many homeowners in Hamilton, Ancaster, Dundas, Stoney Creek, Waterdown, Burlington, Oakville, Milton and across Halton, adding on costs less stress than moving, lets you keep your current mortgage and location, and avoids the realtor commissions, land transfer tax and closing costs that come with buying a bigger house.
what we build
Types of Home Additions
Whatever space your family is missing, there is an addition that fits your home, your lot, and your budget.
Second Storey Additions
Build up to add bedrooms or a primary suite without losing yard space. Older homes usually need foundation and framing reinforcement, which we coordinate with a structural engineer.
Rear & Side Additions
Extend outward for a bigger kitchen, family room or open-concept main floor. Less disruptive than building up, but it uses yard space and must respect setback rules.
In-Law & Secondary Suites
A self-contained space with its own kitchen, bath and often a private entrance, ideal for family or rental income. Designed and built to the Ontario Building Code.
Bump-Out Additions
A small two-to-four-foot projection that adds room to a tight kitchen, bath or bedroom. The most economical way to gain a few critical feet.
Garage Conversions
Turn an existing garage into finished living space without changing your footprint. Must meet code for insulation, ceiling height and egress, which we handle.
Above-Garage Additions
Add a new room above the garage for an office, guest suite or bonus room. The structure often needs reinforcement, which we coordinate before design.
Why Choose Design-Build Home Addition Contractors?
Sit back and relax throughout the installation of your home addition as our Heartwood team handles everything for you. As your home addition contractors, we fully manage the project, so you don’t need to deal with juggling multiple trades, messes, or any potential concerns of expanding your space. Focus on enjoying your space with the comforting knowledge that every detail, from permits to final touches, is expertly taken care of.
Do You Need a Permit for a Home Addition in Ontario?
We confirm what your lot allows, setbacks, lot coverage, and height limits, which determines how large your addition can be.
If your plans exceed a zoning limit, we coordinate and guide you through the Committee of Adjustment application.
We initiate the application and prepare the site plans, floor plans and elevations your municipality requires.
We book and coordinate every staged inspection so your addition is fully permitted and code-compliant.
home addition costs
How Much Does a Home Addition Cost in Ontario?
No flat price. Every project is quoted individually after a free consultation.
As a general Ontario market reference (not Heartwood pricing), additions typically run roughly $350 to $500 per square foot in 2026. Here is what moves that number.
Size
More square footage means more foundation, framing, roofing and finishing. The single biggest cost driver.
Type of Addition
A bump-out or garage conversion costs less per square foot than a second storey, kitchen or bath addition.
Structural Work
Reinforcing a foundation, removing load-bearing walls or tying into existing structure adds engineering and labour.
Materials & Finishes
Standard, mid-level or luxury finishes can swing the budget significantly. We show you options in 3D first.
Kitchens & Baths
Plumbing, electrical, ventilation and cabinetry make these the costliest rooms to add or relocate.
Permits
Permit, design and engineering fees vary by municipality and are scoped into your individual quote.
Typical Range
$350 to $500+
per square foot
All figures are general Ontario market references, not Heartwood pricing. Your real number comes from a free consultation and an itemized quote.
Book a free consultation. We will assess your home, talk through your options, and give you a clear, itemized estimate. No obligations.
Our approach is rooted in a deep understanding of both design and budget. As we plan your home addition, our experts share their knowledge at every step, so you stay informed about both the creative and financial sides of the project. The result is an addition that is beautifully designed, built to the Ontario Building Code, and planned around the budget you set.
No matter the addition, we are equipped to handle it. Our in-house team of carpenters, designers and project managers keeps your home addition smooth and stress-free, handling everything from design and permits to framing and final finishing, with no outside contractors to coordinate. This design-build approach delivers superior quality and a seamless experience.
Our dedication to quality materials and craftsmanship is what sets us apart. Your addition is not just built to add space, it is built to last, using premium materials and hardware chosen for durability and finished to the standard that earned us two WEHBA Awards of Distinction.
Experience our dedication to quality firsthand. Learn about our 5-year workmanship warranty by viewing Our Promise.
How Does a Home Addition Work?
A free, no-pressure visit to walk your space, understand how you live and talk through your goals and budget.
Our in-house designers develop your plan and finishes, then show it in 3D so you approve the space before we build.
We initiate your building permit, prepare the drawings and coordinate any engineering or minor variance your project needs.
Our Red Seal Carpenters build it, managed by your project manager, with progress, payments and messages in your client app.
We coordinate every municipal inspection at the right stage, so the work meets the Ontario Building Code throughout.
We walk the finished space with you, then back it with our comprehensive 5-year workmanship warranty.
Why Visit a Renovation Showroom Before a Home Addition?
One place to plan your addition, from first idea to final selections.
Visiting a renovation showroom before you start a home addition is the easiest way to turn ideas into firm decisions, and our Ancaster renovation showroom is built to do exactly that. Located at 7-680 Tradewind Drive in Ancaster, the showroom lets you explore finishes, cabinetry, millwork and material selections all in one place, with the same in-house team that will build your addition.
Choose from a wide variety of premium selections.
Browse all the finishes and selections you will need for your renovation in one place.
Selections that have been tried and tested by the experts.
Finishes, cabinetry and millwork on display, the same our team builds with.
HOME ADDITION FAQ:
Costs, Permits & Timelines in Ontario
How much does a home addition cost in Ontario?
There is no single price because every project is quoted individually after a free consultation. Your final number depends on the size and type of addition, whether you build up or build out, the level of finishes and how much structural, plumbing and mechanical work is involved. As a general Ontario market reference, not Heartwood pricing, home additions in 2026 commonly run from roughly $350 to $500 per square foot for standard builds. To get a real figure for your home in Hamilton, Burlington, Oakville or Milton, book a free consultation for a detailed quote based on your actual plans.
Do I need a permit for a home addition in Ontario?
Yes, nearly every home addition in Ontario requires a building permit because you are adding floor area and changing the structure of the house. Additions such as second storeys, rear and side extensions, bump-outs, sunrooms and attached garages all fall under the Building Code. We handle this for you: Heartwood initiates the building permit application on your behalf and coordinates the required inspections throughout construction. If your project needs a minor variance, we coordinate and guide you through that process with your municipality.
How long does a home addition take?
Timelines depend on the size and complexity of your addition and on the municipal approval process, so we give you a realistic schedule with milestones as part of your project plan. A larger or more structural project such as a second storey addition takes longer than a single room bump-out, and design plus permit approvals happen before construction begins. You can follow your timeline, milestones, payments and messages in real time through our client app.
Can I stay in my home during a home addition?
In many cases yes, and whether it is comfortable to do so depends on the scope of the work and which part of your home is affected. A contained addition that does not disrupt your kitchen, bathrooms or main living areas is usually easier to live through than a large second storey or a project that ties into core systems.
Is a home addition cheaper than moving?
For many Hamilton, Burlington, Oakville and Milton homeowners, adding on lets you get the space you need without the costs of selling, buying and moving, and it lets you keep the home, neighbourhood and location you already love. A home addition such as a second storey, rear extension, in-law suite or bump-out can be tailored exactly to how your family lives.
Do you build in-law suites and secondary suites?
Yes. As a full-service design-build firm, we design and build in-law suites and secondary suites along with second storey additions, rear and side extensions, bump-outs and garage conversions. Our in-house team handles the design, interior design, millwork and carpentry, with Red Seal Certified Carpenters on staff and accredited interior designers, and we coordinate structural engineering and architecture where a project calls for it. You will see your space in 3D renderings before construction begins, so you know exactly what your suite will look like before any work starts.
What areas do you serve for home additions?
Heartwood is based in Ancaster and serves homeowners across Hamilton, Ancaster, Dundas, Stoney Creek, Waterdown, Flamborough, Binbrook, Burlington, Oakville, Milton and Grimsby. Whether you are planning a home addition in Hamilton, a second storey in Burlington or an in-law suite in Oakville or Milton, our team works throughout the region. You can reach us at 289-208-2612 or visit our showroom at 7-680 Tradewind Drive in Ancaster to talk through your project and book a free consultation.
Do you handle the design and project management?
Yes, that is the heart of the design-build approach. With Heartwood you get design, interior design, project management, millwork and carpentry all in-house under one accountable team. We provide 3D renderings before construction begins, and our client app lets you track progress, payments and messages, all backed by a comprehensive 5-year workmanship warranty.
A reputation for excellence.
From the first time you meet with our team, you’ll understand the Heartwood Difference. We maintain professionalism and respect with everyone so you feel confident and comfortable expressing your dreams for your home with us. Once you invite Heartwood Renovations into your home, you’ll be glad you did. With our comprehensive and one-stop-shop approach, you can sit back and relax while we handle the rest.
Our exceptional workmanship, elite-grade materials, and refined processes are geared towards providing you with the space and service you dream of, with quality that will last. Explore our gallery to find inspiration for your project or discover the beauty Heartwood has brought to homes across the GTA.
Free Consultation
A free, no-obligation consultation and an itemized estimate built around your home.