Services > Permit Drawings  > ARU - Addition Residential Unit Permit Plan > GTA

ARU - Additional Residential Unit Plan Drawings - GTA ON

1. What is an Additional Residential Unit (ARU)?

 

An ARU is an independent dwelling unit with a kitchen, bathroom, and sleeping area, which can be located in:

 

• A basement (Basement Apartment)
• An addition to the main house (Attached ARU)
• A detached building (Garden Suite, Coach House, Laneway House)

 

ARUs provide rental income opportunities for homeowners and help increase the housing supply in Ontario.

 

2. Permit Plan Process for ARUs in Ontario

 

Step 1: Feasibility & Zoning Compliance Check

 

Before designing an ARU, the following must be verified:

 

• Zoning Bylaws (Confirm if ARUs are permitted in that zone).
• Lot size & setbacks (Ensure compliance with local setback, height, and lot coverage regulations).
• Parking requirements (Most municipalities require at least 1 parking spot per ARU).
• Fire Code & Building Code Compliance (Fire separations, egress requirements, HVAC separation, etc.).
• Septic System Capacity (For rural properties, the system must support the additional unit).

If any zoning issue arises, a Committee of Adjustment approval may be required.

 

Step 2: Preparation of Drawings & Documentation

 

The following drawings and reports are required for an ARU Building Permit:

 

Architectural Drawings

 

• Site Plan (Property layout, existing structures, and proposed ARU location).
• Floor Plans (Existing and proposed layouts, showing rooms, walls, plumbing, HVAC).
• Elevations (Exterior views for attached or detached ARUs).
• Sections & Details (Construction details, insulation, and structural components).

Structural Drawings (If Needed)

 

• Foundation details, beam and column specifications, framing plans.
• Engineer’s Stamp may be required for major structural modifications

 

Mechanical, Electrical & Plumbing (MEP) Plans

 

• HVAC System (Separate heating and ventilation may be required).
• Electrical & Plumbing Layouts (New fixtures, circuits, fire alarms).

 

Ontario Building Code (OBC) Compliance Reports

 

• Energy Efficiency Report (SB-12 Form) for newly built ARUs.
• Fire & Sound Separation Plan (Required if the ARU is within the main house).

Step 3: Submission to the Municipality

 

The permit application must be submitted to the local Building Department in one of the following ways:

 

• Online Submission (Most municipalities have digital portals for permit applications).
• In-Person Submission (Plans are submitted at the local city hall or permit office).

 

Documents Required for Submission:

 

• Completed Building Permit Application Form.
• Permit fees payment (Varies by municipality).
• All architectural, structural, and MEP drawings.
• Owner’s Authorization (if submitted by a designer or contractor).
• Zoning Approval Letter (if required).

 

Step 4: Municipal Review & Approval Process

 

• The city reviews the submission for zoning compliance, safety, and structural integrity.
• If additional information is required, revisions may be requested.
• Once approved, the Building Permit is issued, and construction can begin.

 

3. Who Can Prepare & Submit ARU Plans?

 

• Licensed Architect or Engineer (For complex or detached ARUs).
• BCIN-Certified Designer (For simpler ARUs within their scope).
• Homeowner (Limited Scope) (Only if qualified under the Ontario Building Code Act).

 

4. What is Delivered? (Final Permit Package)

 

• Architectural & Structural Drawings (Stamped if needed).
• Energy Efficiency Report (SB-12) for new ARUs.
• Fire & Soundproofing Compliance Report.
• Site Plan & Zoning Analysis.
• Building Permit Approval Document (Issued by the city).

 

5. How Long Does the Process Take?

 

• Preparation of Drawings: 2-4 weeks (Depending on complexity).
• Municipal Review & Approval: 4-8 weeks (Varies by city).
• Total Timeline: 6-12 weeks (From design to permit issuance).

 

6. Which Bylaws & Codes Must Be Followed?

 

• Ontario Building Code (OBC) – Covers fire safety, structural integrity, energy efficiency.
• Municipal Zoning Bylaws – Regulates lot coverage, setbacks, height restrictions.
• Ontario Fire Code – Ensures proper fire separations, smoke alarms, egress.
• Accessibility for Ontarians with Disabilities Act (AODA) – If required.