Top 7 Things to Know Before Starting a Home Addition in Ontario

Thinking About Expanding Your Home?

Whether you’re adding a second storey, building out the back, or extending your kitchen and living space, a home addition is a smart way to create more room without moving. But in Ontario, it’s not as simple as drawing up a plan and hiring a contractor.

At Lush Builds, we guide homeowners through every step—design, permits, construction, and beyond. Here’s what you need to know before you begin.

1. You’ll Likely Need a Zoning Review (and Possibly a Minor Variance)

Every municipality in Ontario has zoning bylaws that regulate:

• Setbacks (how far your home must be from property lines)

• Height limits

• Lot coverage (how much of the land can be built on)

We always start by conducting a zoning and bylaw review. If your plans exceed what’s allowed, we can manage the Committee of Adjustment process to request a minor variance.

2. Structural Integration Matters—A Lot

When you’re adding on to an existing home, structural compatibility is key:

• Does the foundation need reinforcing?

• Can your roof support a second storey?

• Will new footings be required?

Our structural engineers evaluate your existing home and ensure everything is designed to Ontario Building Code standards—while maintaining the safety and integrity of the original structure.

3. Permits Are Mandatory—and Can Take Time

Every addition in Ontario requires a building permit. The complexity of your project (and your municipality’s workload) will affect the timeline. We take care of:

• Architectural and structural drawings

• OBC compliance

• Permit applications and revisions

We proactively work with municipalities to expedite approvals wherever possible.

4. Home Additions Require Strategic Design (Not Just Extra Space)

More space doesn’t mean better space unless it’s functional and beautiful. We work with you to:

• Match the architectural style of the existing home

• Maximize layout efficiency and flow

• Integrate natural light and views

• Future-proof the design for aging-in-place or resale

We use 3D renderings and virtual walkthroughs to help you see your addition before it’s built.

5. Utilities and HVAC May Need Upgrades

Adding square footage affects more than just walls. You may need:

• A larger electrical panel

• Upgraded plumbing

• A new HVAC zone or high-efficiency furnace/AC

Our mechanical designers handle these layouts in-house, making sure your home addition is both comfortable and code-compliant.

6. Budget and Timeline Expectations

Ontario home additions can cost anywhere from $250–$400/sq ft, depending on:

• Foundation work

• Structural complexity

• Interior finishes

• Accessibility of the site

A typical addition project takes 4 to 6 months from design to completion. We provide fixed-price proposals and transparent scheduling to avoid surprises.

7. Work with a Design-Build Team for Best Results

Unlike hiring an architect, engineer, and contractor separately, a design-build firm like Lush Builds offers:

• One team from start to finish

• Integrated budgets during the design phase

• Seamless communication and project management

• Fewer delays, less rework, and better results

Let’s Make Your Home Work Smarter for You

Whether you’re planning a one-room bump-out or a full second-storey addition, Lush Builds is your partner from concept to construction.

✔️ Zoning + Permits

✔️ Design + Structural Plans

✔️ Construction Management

✔️ Real-Time Budgeting

✔️ Builder-Level Experience

📞 Ready to Start Your Home Addition in Ontario?

Book a free consultation with our expert design-build team and turn your vision into reality.