What is Wexler Custom Builders?

Wexler Custom Builders manages 3 data types including projects. Helps you organize, track, and share your work in 1 place for teams and solo users.

Second storey addition Toronto — Wexler Custom Builders

Home Addition Guide

Second Storey Additions in Toronto:
Cost, Process & What to Expect

Direct Answer

A second storey addition in Toronto costs $350K–$1.5M+ and takes 12–18 months from consultation to occupancy, including 3–6 months for permits. Most homes can support a second storey, though some require foundation reinforcement first.

A second storey addition is one of the most transformative things you can do to a Toronto home — doubling your living space without losing your backyard, your neighbourhood, or the community you've built. It's also one of the most complex residential construction projects you can undertake.

This guide covers everything you need to know before you start: realistic costs, accurate timelines, the permit process in Toronto, and the questions most homeowners wish they'd asked at the beginning.

"A second storey addition done right adds more than square footage — it adds value, function, and permanence to your home. Done poorly, it's one of the costliest mistakes a homeowner can make."

— Robby Wexler, Principal

Investment

How Much Does a Second Storey Addition Cost in Toronto?

Second storey addition costs in Toronto range from $350,000 to $1.5M+ depending on size, finish level, structural complexity, and neighbourhood. Here are realistic ranges based on projects we've completed:

Basic Second Storey Addition

$350K – $550K

Standard finishes, 1,500–2,000 sq ft, existing foundation adequate

Mid-Range Second Storey

$550K – $900K

Premium finishes, custom millwork, 2,000–3,000 sq ft

Luxury Second Storey Addition

$900K – $1.5M+

High-end finishes, complex roofline, structural upgrades, large footprint

Rear Addition (1–2 storey)

$300K – $750K

Simpler structural tie-in, often combined with second storey work

Note: All figures are in CAD. Costs vary significantly based on your specific home, neighbourhood, and desired finish level. Contact us for a project-specific estimate.

Process

The 4 Phases of a Second Storey Addition

Feasibility & Design

1–3 months

Structural assessment, zoning review, architectural drawings, permit application. Your builder and architect assess load-bearing walls, existing foundation capacity, and any heritage or conservation district constraints.

Permits

2–6 months

City of Toronto building permits for additions are reviewed by multiple departments. Expect longer timelines in heritage conservation districts like Rosedale, Forest Hill, or The Annex. An experienced builder can accelerate this with complete, accurate submissions.

Construction

4–8 months

Structural work, framing, rough-in mechanical/electrical/plumbing, roofline integration, exterior cladding, then full interior finishing. Your home remains partially habitable during most of this phase.

Finishing & Handover

1–2 months

Millwork, flooring, fixtures, painting, final inspections and occupancy sign-off. This is where quality really shows.

Frequently Asked Questions

Do I need a permit for a second storey addition in Toronto?

Yes. All second storey additions in Toronto require a building permit. Depending on your neighbourhood, you may also need heritage approvals, Committee of Adjustment variances, or conservation district review. A knowledgeable builder will handle all submissions on your behalf.

How long does a second storey addition take?

From first consultation to occupancy, a second storey addition in Toronto typically takes 12–18 months. The permit process alone can take 3–6 months depending on complexity and neighbourhood. Construction itself is generally 4–8 months.

Will my family be able to live in the house during construction?

Usually yes — for most of the project. The most disruptive phase is when the roof comes off, which typically takes 1–2 weeks. Many families choose a short-term rental during this period and return once the new roofline is weathertight.

Is it cheaper to add a second storey or build a new home?

It depends on your existing structure and how much you love your neighbourhood. If your foundation is sound and the neighbourhood is where you want to be, a second storey addition is usually more cost-effective. However, if major structural upgrades are needed, a teardown-rebuild can sometimes make more financial sense.

Can I add a second storey to any Toronto home?

Most homes can support a second storey addition, but some require foundation or structural reinforcement first. Heritage-designated homes have additional design constraints. A thorough structural assessment at the start of the project will identify any issues early.