Ceiling Height Reductions:

• Secondary suites: 1.95m minimum (vs. standard residential 2.3m)
• Under beams/ducts: 1.85m minimum
• Stairs under beams/ducts: 1.85m minimum clear height

HVAC Separation:

• Air duct systems serving dwelling units cannot be directly interconnected
• Each dwelling unit requires separate temperature control
• All secondary suites need separate furnaces (applies to homes under 5 years old)

Alarm Systems:

• Smoke alarms: Interconnected between suites (wireless or hardwired permitted)
• Carbon monoxide alarms: Interconnected between suites (hardwired only - no wireless)

2. Soil Gas Control (Radon Protection)

Universal Requirements:

• All buildings except garages/unenclosed areas require soil gas control
• Air barrier system mandatory
• Subfloor depressurization rough-in required for future radon system installation

Two Rough-in Options:

• 1. Gas-permeable layer with inlet/outlet system
• 2. Clean granular material with minimum 100mm diameter pipe

High-Risk Areas:

• Where radon exceeds 200 Bq/m³, active depressurization system required
• Three specific geographical areas identified in Article 9.1.1.7

3. Guards and Safety Updates

Window Guards (NEW):

• Openable windows 1.8m+ above grade require permanent guard or opening limiter
• Applies when windows within 900mm of floor surface

Stair Guards:

• Triangular openings: Maximum 150mm (6") diameter sphere passage
• Balusters must resist 100mm (4") opening under 0.1 kN load
• Open risers prohibited except for specific applications (single dwelling units, maintenance stairs, etc.)

4. Farm Buildings (New Part 2)

Application:

• Farm buildings over 600m² now regulated by OBC 2024 Part 2
• Buildings under 600m² still follow 1995 National Farm Building Code
• Must meet definition of farm building regardless of size

Agricultural Occupancy Classifications:

• G1: High hazard (livestock with below-floor manure storage, feed mills)
• G2: General agricultural (animal housing, farm workshops, equipment storage)
• G3: Greenhouses
• G4: No human occupancy (digesters, grain bins, silos)

COMMERCIAL IMPACT (Part 3 & 4)

1. Fire Safety Enhancements

• More occupancies require sprinkler systems
• Fire alarms mandatory for ALL sprinklered buildings
• Pull stations required at every principal entrance and exit
• Standpipe water pressure increased from 450 kPa to 690 kPa
• Hose connections must be installed in exits

2. Accessibility Updates

Barrier-Free Path:

• ALL pedestrian entrances must be barrier-free (previously only portion required)
• Direct barrier-free path must connect to public thoroughfare, parking, loading zones

Enhanced Signage:

• Visual information required for washrooms, showers, elevators, parking spaces
• Directional signs with visual information throughout building
• Tactile attention indicators at unenclosed stair tops and drop edges >300mm

Carbon Monoxide Alarms - Expanded Requirements

Residential Locations:

• Sleeping rooms adjacent to garages or garage attics/crawl spaces
• Adjacent to each sleeping room
• Every storey without sleeping room
• Bachelor suite main areas
• Suites with fuel-burning appliances or flues

Commercial/Other Buildings:

• Public corridors serving residential suites with forced-air fuel-burning appliances
• Service rooms with fuel-burning appliances
• Laundry rooms with fuel-burning equipment

Installation Requirements:

• Permanently connected with battery backup
• Visual signaling component required
• Interconnected within suites and between primary/secondary suites
• Conform to CAN/CSA-6.19 and UL 2034

Ventilation System Updates

New Terminology:

• "Non-heating season ventilation" and "heating season ventilation" introduced
• Principal ventilation capacity now ranges based on bedroom count

Enhanced Requirements:

• Outdoor air separation increased from 900mm to 1800mm from exhaust outlets
• Soffit clearance: 1800mm from exhaust outlets to vented soffits
• Kitchen supplemental exhaust: minimum 50 L/s capacity
• Bathroom supplemental exhaust: minimum 25 L/s if not served by principal system

ICF Construction Expansion

• Part 9 ICF design expanded to all buildings
• Light-frame or flat ICF construction permitted
• Maximum 2 storeys, 3m floor-to-floor height
• Concrete core increased from 140mm to 150mm minimum
• Cladding attachment permitted to web fastening strips

Lumber and Framing

Dimensional Changes:

• Stud spacing: soft conversion to 300mm, 400mm, 600mm (from 305mm, 406mm, 610mm)
• Both conversions acceptable for framing dimensions

Pressure-Treated Wood:

• Connectors and fasteners must be corrosion-resistant
• Galvanized, stainless steel, or equivalent corrosion-resistant materials required
• Exception for dry interior environments with specific preservatives

Snow Loading

• Updated ground snow loads reflecting current climate data
• Roof steps over 2m where upper roof ≤1:6 slope and >600m² require additional calculations
• Enhanced drift provisions for complex roof geometries

Documentation Requirements

Enhanced Drawings:

• Site plans: accessible routes, grading details, path dimensions/slopes
• Floor plans: accessibility compliance notes, door swing clearances
• Building sections: insulation details, air barrier continuity
• Details: soil gas control, secondary suite separations

New Compliance Statements:

• Secondary suite compliance (where applicable)
• Soil gas control system compliance
• Enhanced fire protection measures
• Structural load confirmations

Municipal Review Process

Expected Changes:

• 20-30% longer review times initially
• Enhanced scrutiny of secondary suite compliance
• Soil gas control system verification
• Carbon monoxide alarm placement review

Residential CostImpacts

Secondary Suite Additions:

• Smoke-tight barrier installation: $2,000-4,000
• HVAC system separation: $3,000-8,000
• Electrical modifications: $1,500-3,500

Soil Gas Control:

• Basic rough-in system: $800-1,500
• Enhanced systems (high-risk areas): $2,500-5,000

Safety Upgrades:

• Window guards/limiters: $200-500 per window
• Stair guard modifications: $1,000-3,000

Commercial CostImpacts

• Fire protection enhancements: +1-3%
• Accessibility improvements: +3-8% depending on building type
• Enhanced sprinkler/alarm systems: +2-5%

Timeline Considerations

Projects January-March 2025:

• Option 1: Use OBC 2012 (if drawings substantially complete before Jan 1, 2025)
  • HVAC system separation: $3,000-8,000
  • Electrical modifications: $1,500-3,500

Timeline Considerations

Projects January-March 2025:

• Option 2: Use OBC 2024
  • Future compliance assured
  • Learning curve required
  • Potentially longer approval times

Projects After March 31, 2025:

• Mandatory OBC 2024 compliance
• No grandfathering options

Secondary Suites

• Smoke-tight barrier: 15.9mm Type X gypsum board specification
• Ceiling heights: 1.95m minimum (1.85m under beams/ducts)
• Separate HVAC systems designed
• Alarm interconnection systems specified
• Door requirements: solid-core 45mm with self-closing devices

Soil Gas Control

• Air barrier system detailed
• Subfloor depressurization rough-in designed
• High-risk area assessment completed
• System labeling and access provisions included

Fire Protection

• Penetration sealing detailed (CAN/ULC-S115 compliance)
• Outlet box limitations verified
• Enhanced sprinkler/alarm requirements addressed

Key Changes:

• Building to first manhole distance increased from 30m to 75m
• Stack termination minimum 1.8m from property line
• Air admittance valves: 100mm above fixture drain (reduced from previous)
• Sump pit requirements: minimum 750mm deep, 0.25m² area

Required Knowledge Areas

• Secondary suite design and compliance
• Soil gas control system design

• Enhanced fire protection requirements
• Updated ventilation standards
• New structural load requirements

Training Opportunities

• OBC 2024 overview courses
• Secondary suite design workshops
• Soil gas control implementation
• Municipal coordination seminars

Official Resources

• Ontario Building Code: ontario.ca/building-code
• MMAH Updates: ontario.ca/ministry-municipal-affairs-housing
• BCIN Professional Development: bcin.com

eQuote360 BCIN Network

OBc compliance review:

• Secondary suites/ legal basement permits
• ADU/ARU design and permits
• Garden suites
• Coach houses
• Laneway hosues
• Multiplex conversions
• Home additions designs and permits
• Custom residential design and permits
• Garage conversions
• Garages/ and carports
• Decks

• 1. This cheat sheet highlights key changes only - consult official OBC 2024 O. Reg. 163/24 as amended by O. Reg. 203/24 for complete requirements
• 2. Municipal interpretations may vary - confirm with local building departments
• 3. Complex projects may require professional engineering consultation

• 4. Always verify current requirements before finalizing designs

Ready to master OBC 2024? Use eQuote360 to connect with qualified professionals who can support your transition to the new code requirements

© 2024 eQuote360. This professional resource is designed for BCIN designers and building permit professionals. Always consult official code documents and professional engineers where required.