Navigating the 2024 Ontario Building Code

By Paul Riopel

Updated on June 9, 2026

Large wooden stamp with the word REGULATION on it, placed on official government forms and documents

On April 10th, the Ontario government introduced its newest Building Code, signaling a significant step towards simplifying regulations in the construction sector. This update aims to make it easier for the industry to navigate compliance requirements while ensuring that safety and performance standards remain uncompromised. By reducing regulatory hurdles, the revised Building Code seeks to facilitate smoother construction processes and promote housing development in the province.

While that all sounds straightforward enough, we at Reno Quotes know that building codes can often be difficult to navigate. So, to help facilitate this transitional period towards the 2024 Ontario Building Code, we've devised this article to shoulder some of that burden and simplify its key points. Here's what you need to know.

What Is the Ontario Building Code Concerned With?

construction workers 

The Ontario Building Code, regulated by the Building Code Act, sets forth detailed requirements and minimum standards for construction projects. It prioritises public safety, fire protection, resource conservation, environmental integrity, and accessibility. Its core objective is to uphold uniform building standards to promote public safety.

What's the Latest Ontario Building Code Update for 2024?

construction machine

The 2024 Building Code aims to simplify procedures within the construction industry and align more closely with the National Building Code. By addressing over 1,730 technical differences between provincial and national requirements, it seeks to promote greater consistency and efficiency.

Developed in collaboration with key stakeholders such as building officials, fire prevention authorities, architects, engineers, builders, and industry representatives, this latest iteration of the Building Code underscores Ontario's commitment to upholding stringent standards of public health, safety, and building performance in both new constructions and renovations.

Details about the release of the 2024 Building Code were communicated through CodeNews (issue 354), an email subscription service offering updates on the code, ministerial rulings, amendments to the Building Code Act, decisions from the Building Code Commission, and authorisations from the Building Materials Evaluation Commission. While key information, including transition schedules, is outlined below, the Ontario Association of Architects (OAA) strongly recommends that all its members subscribe to this email publication for comprehensive updates.

New Building Code Format

In quite a dramatic shift, the entire format of the Ontario Building Code is getting revamped; it has been reduced to only a singular page. This single page references, for one, the National Building Code of Canada (NBC) 2020 — a 1,500-page document outlining the technical specifications for designing and constructing new buildings, as well as guidelines for modifying, repurposing, or demolishing existing structures. The Building Code also now references the new 2024 Ontario Amendment document for the differences to the NBC in Ontario.

Production of digital and print copies of the Building Code Compendium are currently underway. CodeNews subscribers will be the first notified when they are made available. The OAA will also notify its members.

Transition Timeline

The announcement of the new Building Code on April 10th, 2024, marks a significant development in Ontario's construction landscape. However, its implementation won't occur until January 1st, 2025. Following this date, a transitional phase lasting three months, until March 31st, 2025, will allow for the acceptance of applications with substantially complete drawings. Come April 1st, 2025, all permit applications must align with the regulations outlined in the updated 2024 Ontario Building Code. This transition period offers stakeholders time to adjust to the new requirements before full enforcement takes effect.

Furthermore, the Ministry of Municipal Affairs and Housing (MMAH) is creating a thorough training program to aid the industry in grasping the new regulations of the 2024 Ontario Building Code. Additionally, the Ontario Association of Architects is collaborating with industry partners via Engineers, Architects & Building Officials (EABO) to develop comprehensive education and training sessions that unite key users of the Code in understanding the changes, implementation strategies, and transition rules. A dedicated session will be held at the OAA Conference in Niagara Falls in May to address these topics.

Here is a quick summary of important dates:

  • April 10th, 2024: Filing and release of the 2024 Ontario Building Code.

  • January 1st, 2025: 2024 Ontario Building Code comes into effect.

  • March 31st, 2025: Deadline for permit applications using the 2012 Ontario Building Code where working drawings were substantially complete before January 1, 2025.

  • April 1st, 2025: All permits must use the 2024 Ontario Building Code.

Summary of the 2024 Ontario Building Code's Key Points

three people in front of a computer on a construction site

As a first change to the Building Code, Ontario has taken significant strides towards alignment with the National Building Code's regulations for two-unit houses, bringing them in line with secondary suite provisions, albeit with a notable exception regarding minimum suite sizes. Ontario's decision to retain flexibility in this aspect underscores its commitment to meeting housing objectives while also minimising associated costs.

Moreover, the province has introduced a groundbreaking amendment to the Building Code, mirroring the NBC's guidelines for large farm buildings. This pivotal change addresses regulatory gaps and modernises standards to reflect evolving agricultural practices, all the while upholding stringent safety measures akin to those applied to conventional buildings.

The Ontario government has harmonised its policies with the NBC's recommendations to mitigate radon exposure. New housing constructions are now mandated to incorporate provisions for a subfloor depressurisation system, offering a proactive approach to combat potential health risks. Furthermore, updates to references and clarifications regarding the necessity of such systems for buildings with limited occupancy hours underscore Ontario's commitment to ensuring public safety.

Additionally, it has aligned its regulations with the NBC's protocols concerning fire protection systems, encompassing standpipes, fire alarms, and fire sprinklers. 

Furthermore, Ontario has enhanced its standards for prefabricated septic tanks and sewage holding tanks by introducing a safety screen requirement beneath cleanout covers. Moreover, revisions pertaining to Type A Dispersal Beds specify the materials designated for the 'mantle,' exemplifying Ontario's approach to ensuring the integrity and safety of wastewater management systems.

How Often is the Ontario Building Code Updated?

Updates to Ontario's Building Code, including new editions or significant revisions, typically occur every five years to align with revisions made to the National Construction Codes.

Cutting Red Tape to Build More Homes Act, 2024

The major updates to the Building Code are part of a larger move by the Ontario government called Bill 185: Cutting Red Tape to Build More Homes Act, 2024, part of the province's Spring 2024 Red Tape Reduction Package. With a goal of building 1.5 million homes by 2031, the provincial government's new bill's stated intention is to streamline approvals and increase the development of both housing and infrastructure across Ontario.

Bill 185, as outlined by the Province, focuses on several key themes, including:

  • Accelerating home construction while reducing costs.

  • Emphasising infrastructure development for housing projects through a new "use it or lose it" mechanism to address project delays.

  • Enhancing consultation processes and providing municipalities and builders with increased certainty to expedite home construction, including by restricting third-party appeals to the Ontario Land Tribunal.

  • Diversifying housing options to accommodate a broader range of individuals, achieved through streamlined approvals for student housing, promotion of standardised designs to minimise delays and expenses (including for modular homes), and endorsement of innovative construction techniques such as mass timber.


Get 3 quotes for your renovation project

RenoQuotes.com can help you get quotes from a general contractor. By submitting your project, we’ll put you in contact with top-rated contractors. Fill in the form on the homepage (it only takes a few minutes) and get estimates from trusted professionals.

Dial 1-844 828-1588 to speak with one of our customer service representatives.

Get 3 free quotes for your project!

Submit a project and get 3 free quotes!

Looking for something else?

Table of contents

6 min read

Find contractors near you

Enter your postal code



Related articles

The latest industry news, interviews, technologies, and resources.

9 min read

Editorial Team

08 Oct 2024

Women in the Construction Industry

In this day and age, 48% of construction companies with over 25 workers are hiring women. Albeit women still solely represent a meagre 3.8% of the industry’s workforce, there was a long battle beforehand to make it to this point. And, after reading this article, you’ll come to understand how hard it is now to picture a high-performing team without these valuable players alongside the men.

Information and news on the construction sector
3 min read

Karine Dutemple

19 Aug 2025

The Construction Industry’s Economic Recovery Plan

If you are a renovation contractor, you are likely to have difficulty finding qualified employees to fill vacancies in your business.

8 min read

Editorial Team

19 Aug 2025

How Will the Construction Industry Shape Itself Following Bill 51?

Bill 51—an Act to modernize the construction industry—is a legislative proposal slated to bring significant reform in the construction industry. Following a period of understanding its background and basic principles, it’s rather difficult to determine whether this proposed legislation will reach its intended purpose or if it’ll simply negatively impact the lives of a part of the province’s workforce.  

Advice for contractor
6 min read

Editorial Team

08 Nov 2023

Our Kitchen Sink Shopping Guide

The saying “everything but the kitchen sink” is one you’ve surely heard many times in your life. This speaks to the importance of the kitchen sink and since it is used multiple times on a daily basis, it’s essential to settle on a design you’ll love to look at and use constantly. We’ve prepared this guide to help you choose the sink that’s right for you!

Kitchen
3 min read

Cynthia Pigeon

20 Apr 2026

Kitchen Bump-Out Extension Cost in Canada in 2026

In 2026, across Canada, a typical kitchen bump-out (or micro-extension) often falls between $30,000 and $70,000, depending on structural complexity and region. The cost per square foot generally ranges from $300 to $700, which is higher than for larger extensions due to fixed costs (engineering, mobilization). This estimate includes structure, foundation (often helical piles), high-performance insulation suited to Canadian climates, and interior finishing. While the price per square foot is higher than new construction, compared to a full multi-storey addition (often $150,000+), a micro-extension limits overall budget impact while addressing a specific space constraint.