OHBA Member Update - Ontario Building Code
The newly harmonized next edition of the Ontario Building Code (OBC) was filed on April 10, 2024. This resulted in over 1,730 provisions changing within the next code. OHBA remains committed to working with MMAH and other key stakeholders, such as the Ontario Building Officials' Association, to ensure a successful transition to 2024 OBC.
Resources
- For the Building Code Regulation on E-laws, click here.
- Subscribe to Ontario CodeNews to receive the latest information from the Ministry of Municipal Affairs and Housing.
Key Dates and Transition Plan
- The filing of the next edition took place on April 10, 2024; however it will not come into effect until January 1, 2025.
- Using a "Transition Plan," MMAH has extended the lifespan of the 2012 code by 9 month, with a 3-month extension for permit applications that are substantially complete by December 31, 2024, based on requirements of the 2012 code.
- During this transition period, only one edition of the Building Code (either 2012 or 2024) could be used in the design and construction of a building. The version of the building code that applies at the time of permit application is the version that will continue to apply to the building throughout processes of plans review, permit issuance, construction, inspection, and occupancy of buildings.
- March 31, 2025 - Deadline for permit applications using the 2012 Ontario Building Code, where working drawings were substantially complete before January 1, 2025.
- April 1, 2025 - All permit applications must use the 2024 Ontario Building Code.
Proposed Code Changes that ARE NOT Moving Forward Within the 2024 OBC
There are two key items that were proposed for adoption into the 2024 Ontario Building Code that will not be moving forward within the next edition as they did not meet the key criteria applied under the Ministry's analysis:
- Energy Efficiency for Houses and Large Buildings. Note: Ontario will not be adopting Tier 1 and Tier 3. Supplementary Standards SB-10 and SB-12 to remain in place.
- Tornado resiliency of houses.
Key Aspects of the 2024 Ontario Building Code
Division A and C administrative changes introduce multiple definitions supporting harmonization with the National Building Code (NBC) and Ontario-only requirements. We recommend that members take the time to review all the proposed changes, but have flagged the following key items to be aware of:
Radon
- Harmonize with the NBC on mitigating the effects of radon in buildings across Ontario.
- Ontario to adopt a proactive approach to address soil gas/Radon by requiring new houses to have a rough-in for a subfloor depressurization system, if subsequently required.
- Changes include corresponding revisions to reference Supplementary Standard SB-9 and a new Appendix Note to clarify that buildings occupied for a few hours a day may not be required to implement soil gas protection methods.
- The OBC to keep the three townships in code that require full radon abatement.
Two Unit Houses (Secondary Suites)
- Harmonize Ontario's two-unit provisions with National, except for National's limitation around minimum suite sizes.
- Secondary suites will require two HVAC systems.
Large Buildings (Accessibility)
- Harmonize with 2020 NBC accessibility requirements where they enhance current OBC requirements.
Structural Design
Fully harmonize with National's recent structural design changes, including:
- Earthquake design: a web-based seismic data tool available for design support.
- Importance categories: revised description of types of buildings.
- Solar panels: provisions to calculate wind and snow loads for roofs with roof-mounted solar panels.
Additional information around the 2024 OBC will be delivered to members through a series of OHBA webinars and training sessions. Please look out for registration in the coming days.
OHBA will be supported by MMAH as they look to roll out the 2024 OBC and have committed to providing members with technical bulletins, webinars and seminars.
DRHBA is hosting an OBC Update session as part of the LEEP session on May 2, 2024 at Deer Creek in Ajax. More details on this event can be found here.
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