Foundation repair is one of the most regulated home improvement categories in Ontario. Structural work on a foundation affects the safety of the entire building and can have legal consequences at the time of sale. Understanding what permits are required and when a licensed engineer must be involved is essential before any work begins.
Building Permits — When They Are Required
Most structural foundation repair work in Ontario requires a building permit under the Ontario Building Code Act, 1992. The following types of foundation work almost always require a permit from your local municipal building department:
- Underpinning (mass concrete, mini-piles, or any method that alters the bearing depth of the foundation)
- Helical or push pier installation
- Wall anchor system installation
- Any structural repair that is reviewed and certified by a structural engineer
- Basement lowering (bench underpinning or full underpinning for added headroom)
What may not require a permit: Crack injection for non-structural cracks (e.g., hairline shrinkage cracks in a poured concrete wall that are not leaking or growing) may not require a building permit in many municipalities — but this varies. When in doubt, call your municipal building department before any work begins.
Structural Engineer (P.Eng.) — When Required
A Professional Engineer licensed in Ontario by Professional Engineers Ontario (PEO) must be involved in all structural foundation assessments and repairs involving:
- Bowing or deflecting foundation walls
- Foundation settlement or differential settlement
- Underpinning of any type
- Helical or push pier installation
- Any crack that may have a structural cause (horizontal, diagonal, or cracks wider than 6mm)
- Design of any structural repair that will form part of a building permit application
The engineer's role is to assess the cause and severity of the problem, specify the appropriate repair, produce drawings for permit submission, and inspect or certify the completed work as required. Do not let a contractor perform structural foundation repair without an independent engineer's involvement on anything beyond a simple crack injection — the engineer works for you, not the contractor.
To verify that an engineer is licensed in Ontario, search the PEO directory at peo.on.ca.
Contractor Qualifications — No Mandatory Licence
Ontario does not have a mandatory trade licence for foundation repair contractors. Anyone can legally market and perform foundation repair work — including underpinning and structural repairs. This makes contractor vetting especially important in this category.
The key requirements you should verify for any foundation repair contractor:
- WSIB clearance: Confirm active WSIB (Workplace Safety and Insurance Board) coverage at wsib.ca before any work begins. Foundation work involves significant physical risk, and an injured worker without WSIB coverage can create personal liability for the homeowner.
- General liability insurance: A minimum of $2 million is standard for residential structural work. Ask for a certificate of insurance.
- Experience with the specific repair type: Underpinning is not the same as crack injection — ask about specific experience with the method they're proposing.
Conservation Authority Considerations
If foundation repair work involves excavation that could affect drainage near a watercourse or wetland, approval from the Renfrew Victoria Conservation Authority (RVCA) may be required under the Conservation Authorities Act, R.S.O. 1990. This is most likely to apply when:
- The property is near a river, creek, or regulated floodplain
- Excavation for underpinning or pier installation could alter how water drains from the site
- The property has been mapped as part of the RVCA's regulated area
Contact the RVCA (rvca.ca) to confirm whether your property is in a regulated area before starting any significant excavation.
Consequences of Unpermitted Work
Foundation repair done without a required permit can create serious problems when you sell the property. A home inspection will flag visible structural repairs, and a buyer or their lawyer may ask for permit documentation. Unpermitted structural work can affect your ability to sell, require retroactive permits (with possible penalties), or in some cases require work to be undone and redone properly.
A properly permitted and engineered foundation repair — while more process-intensive — provides documentation that protects the value of your home.
See also: Building Permits in Renfrew County | Hiring a Contractor in Ontario