Ontario Building Code Section 9.5: Room Sizes and Barrier-Free Design for London Home Construction
Sarah's Expert Insight
OBC Compliance Specialist
"When planning custom builds or renovations in London or Oakville, the measurement of 'finished surfaces' is a critical detail often overlooked by DIYers, leading to failed inspections. At empcontracting.ca Inc. your construction contractor in London, Ontario, we strongly recommend documenting your bathroom stud reinforcement with photos before drywalling to streamline the municipal inspection process and prove compliance with Article 9.5.2.4."
Navigating the complexities of the 2024 Ontario Building Code (OBC) is essential for any successful residential project. As empcontracting.ca Inc. your construction contractor in London, Ontario, we ensure every measurement and design detail meets these rigorous standards for safety and comfort.
9.5.1. Measuring Room Dimensions and Floor Areas
According to Article 9.5.1.1., the dimensions and areas of rooms must be measured between finished wall surfaces and from finished floor to finished ceiling. This ensures that the actual usable space meets the minimum living standards required by the province.
Floor Area Exclusions and Lesser Dimensions
It is important to note that minimum floor areas generally do not include closets or built-in cabinets unless specified. However, the code allows for flexibility under Article 9.5.1.3., where rooms may be smaller than the standard requirements if it can be proven that built-in furniture or specific design choices make the space adequate for its intended use.
9.5.1.2. Designing Combination Rooms
For modern open-concept designs, the OBC allows two areas to be considered a 'combination room' if the opening between them is significant—at least 3 m² or 40% of the wall area. This is a common strategy we use at empcontracting.ca Inc. to create spacious, flow-through layouts in contemporary London homes.
9.5.2. Barrier-Free Design and Future Accessibility
While detached and semi-detached houses are exempt from some full barrier-free requirements, the OBC mandates 'aging-in-place' readiness. Article 9.5.2.4. requires that bathroom stud walls be reinforced during the initial construction phase.
Required Reinforcement for Grab Bars
Contractors must install reinforcement in bathroom walls to allow for the future installation of grab bars for:
- Water closets (toilets)
- Showers
- Bathtubs
This proactive step ensures that homes remain functional for residents as their mobility needs change without requiring major structural renovations later.
Disclaimer: This content is generated from the Ontario Building Code for educational purposes. Always consult with a licensed professional engineer or your local building department before starting any construction project in London, Ontario.