09 Aug Understanding Building Codes for Underpinning Projects in Ontario

Underpinning is a crucial process in construction and renovation, particularly when it comes to reinforcing and stabilizing existing foundations. In Ontario, there are stringent building codes that govern underpinning projects to ensure safety and structural integrity. This blog will explore the key aspects of these building codes and what homeowners and contractors need to know to comply with them.

Building codes are established to ensure that construction practices meet specific safety and performance standards. For underpinning projects, these codes are essential to prevent structural failures, protect the safety of occupants, and avoid legal issues. In Ontario, the Ontario Building Code (OBC) provides comprehensive guidelines for underpinning work.

1. Ontario Building Code (OBC): 

• The OBC outlines the requirements for all construction projects, including underpinning. It provides guidelines on the design, materials, and methods used for underpinning.
• Underpinning must be designed and supervised by a licensed professional engineer, especially when it involves construction below the footing level of an adjacent building or within the angle of repose of the soil.

2. Permit and Inspection Process: 

• Obtaining a building permit is mandatory for underpinning projects in Ontario. This ensures that the project complies with local building codes and standards.
• The permit application must include detailed plans and specifications, which are reviewed by local authorities. Regular inspections are conducted throughout the project to ensure compliance.

3. Angle of Repose:

• The angle of repose refers to the maximum angle at which soil remains stable. Underpinning work that disturbs soil within this angle must be designed by a professional engineer to prevent soil failure and structural issues.

4. Professional Engineering Requirements:

• For underpinning projects that involve construction below the level of adjacent footings or exceed 1200 mm in height, a professional engineer’s design and field review are required. This includes providing testing and reports during the first and last stages of construction.

5. Health and Safety Regulations:

• Compliance with the Occupational Health and Safety Act (OHSA) is critical to ensure the safety of workers on the site. Proper excavation practices, shoring, and the use of personal protective equipment (PPE) are essential.

6. Environmental Considerations:

• The Environmental Protection Act (EPA) requires that underpinning projects do not harm the environment. Measures must be taken to manage soil displacement, control erosion, and prevent contamination of water sources.

1. Hire Qualified Professionals:

• Engage a licensed engineer and experienced contractors for your underpinning project. Their expertise ensures compliance with all building codes and regulations.

2. Conduct Thorough Assessments:

• Perform detailed site and soil assessments to develop an accurate underpinning plan. Understanding the site conditions helps in designing a system that meets all safety standards.

3. Obtain Necessary Permits:

• Submit all required documentation to obtain a building permit. Ensure that your plans comply with the OBC and other relevant regulations.

4. Follow Approved Plans:

• Adhere strictly to the approved underpinning plans. Any changes to the design must be reviewed and approved by the engineer and local authorities.

5. Schedule Regular Inspections:

• Coordinate with local building authorities to schedule inspections at key stages of the project. These inspections verify that the work is being carried out according to code.

6. Implement Safety Protocols:

• Follow all health and safety regulations to protect workers and prevent accidents on the construction site.

The cost of underpinning permits can vary based on several factors, including the complexity of the project, the soil conditions, and the method used. As of January 1, 2024, the fee for underpinning in Toronto is $11.43 per linear meter. This cost includes building permits fees.

Understanding and adhering to building codes is essential for the success of underpinning projects in Ontario. These regulations ensure the safety and stability of structures, protect workers, and prevent legal issues. By hiring qualified professionals, conducting thorough assessments, obtaining necessary permits, and following approved plans, homeowners and contractors can successfully navigate the complexities of underpinning projects while complying with all regulatory requirements.