Basement Renovations

How to Plan a Basement Renovation in Ontario: Permits, Cost & Timeline

7 min read·February 2026

A finished basement can add 20–30% more usable living space to your home without any change to your footprint. In Ontario, basement renovations are among the most popular and highest-ROI home improvement projects — but they require careful planning, the right permits, and a qualified contractor to execute properly.

Do You Need a Permit?

In most Ontario municipalities — including Barrie, Toronto, and York Region — any basement renovation that involves framing, electrical work, plumbing, or the creation of a habitable secondary suite requires a building permit.

Unpermitted basement renovations create significant problems at resale and can invalidate your home insurance. Always pull the proper permits. At Campoli Custom Builds, we manage the full permit process on every project.

Basement Renovation Costs in Ontario (2026)

Basic finishing (framing, insulation, drywall, pot lights, flooring): $35,000–$55,000

Mid-range renovation with bathroom: $55,000–$85,000

Luxury rec room with home theatre, wet bar, and bathroom: $85,000–$140,000

Legal secondary suite (full kitchen, bedroom, bathroom): $90,000–$150,000+

These ranges are for the Barrie/Simcoe County and Toronto GTA markets. Costs depend heavily on square footage, ceiling height, existing conditions, and finish level.

Timeline: What to Expect

Permit application: 2–6 weeks (varies by municipality)

Framing and rough-in: 3–5 weeks

Inspections (typically 2–3 throughout the project): 1–2 weeks total

Insulation, drywall, taping: 2–3 weeks

Finishing (flooring, trim, painting, fixtures): 3–4 weeks

Total: typically 12–20 weeks depending on scope and permit timing

Key Considerations for Ontario Basements

Ceiling height: Ontario building code requires minimum 1.95m (6'5") ceiling height for habitable space. Older homes often have 7' or less — sometimes achievable with dropped beam relocation or underpinning.

Waterproofing: Address any moisture issues before finishing. Water infiltration under finished walls creates mould and significant remediation costs. A qualified contractor will inspect for moisture before framing.

Egress windows: For bedrooms and secondary suites, Ontario code requires egress windows — large enough to escape through in an emergency. Budget $2,000–$4,000 per egress window including well installation.

Ready to Transform Your Basement?

The Campoli Custom Builds team has completed dozens of basement transformations across Barrie, Lake Simcoe, and the GTA — from family rec rooms to full secondary suites. Contact us to schedule a free basement consultation.

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