Barrie ADU Calculator & Guide
Accessory Dwelling Unit (ARU) Eligibility, Regulations & Cost Estimator
Based on Zoning By-law 2009-141 (as amended by By-law 2024-043)
Property Details
Results
Enter your property details to see results
The calculator will check zoning eligibility, maximum ADU size, setbacks, and estimate costs.
Key Regulations Summary (By-law 2024-043)
- Maximum Units: Up to 4 dwelling units per lot (main + 3 ARUs)
- Maximum ADU Size: Smaller of 75 m² (807 sq ft) OR 45% of main dwelling GFA
- Setbacks: 1.2m from side/rear lot lines; 4.0m from other residential buildings
- Height: Maximum 4.5m (14.8 ft), must not exceed main dwelling height
- Parking: 1 space per dwelling unit (tandem permitted)
- Pathway: 1.2m unobstructed path to entrance required
Step-by-Step Process to Build an ADU in Barrie
Confirm Zoning & Eligibility
Verify your property zoning using the City's zoning map or contact Service Barrie. Check that your lot allows ARUs (permitted in R1, R2, R4, R5, RM1, RM1-SS, RM2, RM2-TH, RM3 zones).
Pre-Application Consultation (Optional but Recommended)
Contact Planneroftheday@barrie.ca to discuss your proposal. This helps identify potential issues early. Consider using the City's standardized ARU designs to streamline the process and reduce costs.
Prepare Your Application
Gather required documents: site plan, floor plans, elevations, construction details. If using a custom design, hire a design professional. For standardized designs, purchase full plans from the designer and add your site plan.
Submit Building Permit Application via APLI
Apply online at barrie.ca/APLI. Upload all drawings and documents. Pay permit fees (50% reduced in 2026 for ARUs). Fast Track option available for complete applications - reviewed within 5 business days.
Plan Review & Approval
Building Services reviews for compliance with Ontario Building Code, zoning, and applicable law. Planning Services reviews for zoning compliance. Address any deficiencies promptly. Typical review time: 3-10 business days for Fast Track.
Receive Permit & Begin Construction
Once approved, print your permit from APLI. Post permit on site. Schedule pre-construction inspection to confirm required inspection stages.
Complete Construction & Inspections
Typical inspections include: footings/foundation, framing, plumbing, HVAC, insulation, fire separations, final interior, final exterior. Call before you dig: 1-800-400-2255.
Final Inspection & Occupancy
Schedule final inspection. Upon passing, receive confirmation of occupancy. Apply for fee rebate within 12 months of permit issuance if occupancy achieved.
Register Your Second Suite (if applicable)
Contact Service Barrie at 705-726-4242 or Service.Barrie@barrie.ca to register. Registration ensures fire services, garbage collection, and proper addressing.
Zoning Zones Allowing ADUs in Barrie
| Zone | Permitted ADU Type | Max Units/Lot | Key Restrictions |
|---|---|---|---|
| R1 Residential First Density |
Attached & Detached ARUs | Up to 4 total | Must have municipal street frontage; 1 parking space/unit |
| R2 Residential Second Density |
Attached & Detached ARUs | Up to 4 total | Must have municipal street frontage; 1 parking space/unit |
| R3 Residential Third Density |
Check specific provisions | Varies | May have special provisions (SP) applying |
| R4 Residential Fourth Density |
Attached & Detached ARUs | Up to 4 total | Must have municipal street frontage; 1 parking space/unit |
| R5 Neighbourhood Residential |
Attached & Detached ARUs | Up to 4 total | 1.2m side/rear setbacks; max 4.5m height |
| RM1 / RM1-SS Multiple Residential First |
Attached & Detached ARUs | Up to 4 total | Subject to RM1 standards for main building |
| RM2 / RM2-TH Multiple Residential Second |
Attached & Detached ARUs | Up to 4 total | Townhouse developments may have specific requirements |
| RM3 Neighbourhood Multiple |
Attached & Detached ARUs | Up to 4 total | Minimum 4 attached dwelling units required for main building |
Key Dimensional Standards (Section 5.2.9)
| Maximum ADU Size | Lesser of 75 m² OR 45% of main dwelling GFA |
| Side Yard Setback | 1.2 meters minimum |
| Rear Yard Setback | 1.2 meters minimum |
| Building Separation | 4.0 meters from other residential buildings (O.Reg. 462/24) |
| Maximum Height | 4.5 meters (14.8 ft); must not exceed main dwelling height |
| Lot Coverage | Minimum 45% permitted (O.Reg. 462/24) |
| Pathway Width | 1.2 meters unobstructed to entrance |
Fees & Costs for ADUs in Barrie (2026)
Estimated Permit Fees
Total Project Cost Estimate
Including construction, permits, and professional fees
Cost Breakdown
- Design/Plans: $2,000 - $8,000
Lower end if using standardized designs - Permits & Fees: $260 - $1,000
Includes building, zoning, possible DCs - Site Preparation: $5,000 - $15,000
Excavation, grading, utilities - Foundation: $15,000 - $30,000
Slab, basement, or crawl space - Construction: $100,000 - $250,000
Varies by size and finishes - Utilities/Hookups: $5,000 - $15,000
Electrical, plumbing, HVAC - Contingency (10-15%): Recommended
Money-Saving Tips
City-approved ARU designs significantly reduce plan preparation costs and review time.
Build now to save 50% on permit fees and potentially get full rebate.
Submit complete applications Monday-Thursday for 5-day review (vs. standard 3 weeks).
ARUs may be exempt from Development Charges depending on type and timing. Verify with City.
Key Contacts & Resources
Service Barrie
Phone: 705-726-4242
Email: Service.Barrie@barrie.ca
Hours: Monday-Friday, 8:30am-4:30pm
For: General inquiries, second suite registration, status updates
Planning Services
Email: Planneroftheday@barrie.ca
For: Zoning confirmations, pre-application consultations, planning compliance
Building Services
Portal: barrie.ca/APLI
For: Building permits, inspections, code compliance, permit status
Barrie Fire & Emergency Service
For: Fire safety inspections, smoke alarm requirements, emergency access compliance
Registration ensures fire services know your unit exists for emergency response.
Electrical Safety Authority (ESA)
Phone: 1-877-372-7233
Website: esasafe.com
For: Electrical permits and inspections (separate from building permit)
Lake Simcoe Region Conservation Authority
For: Properties near Kempenfelt Bay, waterways, or environmentally sensitive areas
May require additional permits for construction near watercourses or steep slopes.
Essential Online Resources
- barrie.ca/ARU - Official ARU information and standardized designs
- barrie.ca/APLI - Online permit application portal
- Zoning By-law 2009-141 - Complete zoning regulations
- DADU Registration - Detached unit registration info
- Second Suite Guide (PDF) - Detailed construction guide
