Current Orillia framework
Up to four total dwellings may be possible on a qualifying lot
Overall unit count
Orillia’s current guide permits the principal dwelling plus a maximum of three ADUs on a qualifying lot. This is not an automatic entitlement for every property; the complete proposal must meet current zoning and other requirements.
Units inside the main building
Up to three ADUs may be located within the principal single-detached, semi-detached, or townhouse dwelling when there is no ADU in an accessory structure on the same lot.
Units in a detached structure
Up to two ADUs may be located in one detached accessory structure, provided the total number of dwellings on the lot does not exceed four and the site and building standards are satisfied.
Intensification areas
The City’s guide limits ADUs in Intensification Areas to existing single-detached, semi-detached, and townhouse dwellings. Confirm the property’s zone and overlays before selecting a unit arrangement.
Local approval pathway
Orillia requires zoning approval before the building permit
1. Review the property and concept
Confirm the dwelling type, proposed number and location of units, zone, overlays, parking, servicing, existing approvals, and whether other consultants are required.
2. Obtain the Zoning Certificate
Prepare the required site plan and, for a proposed new dwelling, building elevations. The City requires the Zoning Certificate before the residential building permit application.
3. Coordinate lot grading when required
An addition containing an ADU or a detached ADU generally requires a lot grading plan prepared by an appropriately qualified professional. An interior conversion without an addition generally does not.
4. Complete and submit the permit set
Prepare the forms, plans, construction details, and supporting information, then submit the building permit application through Orillia’s e-Permit Public Portal.
5. Build and complete inspections
After permit issuance, keep the approved plans on site, complete work in accordance with them, book each mandatory City inspection before covering the work, and obtain the required occupancy approval before the new unit is occupied.
Property-specific design
Parking, grading, detached units, and servicing in Orillia
Required parking
The City’s 2026 guide lists three total parking spaces for one ADU, four for two ADUs, and five for three ADUs in the identified zones. A Downtown Area Overlay reduction may apply. Confirm the current requirement and workable parking layout for the property.
Lot grading and drainage
New detached units, additions, basement walkouts, and other site changes can trigger a professionally prepared lot grading plan, drainage review, and related security or inspection requirements.
Detached-building standards
A detached ADU proposal must address the accessory structure’s permanent foundation, yards, height, floor area, access walkway, parking screening, building separation, and relationship to the main dwelling.
Private septic and shoreline constraints
A privately serviced property must demonstrate compliant sewage capacity and may be affected by Lake Simcoe Protection Plan restrictions. Municipal water and sanitary capacity should also be checked for the proposed unit count.
Flood and other overlays
Flood Hazard Overlay, shoreline, heritage, conservation, and other property-specific conditions may add design requirements or approvals. Confirm them before relying on a layout.
Frequently asked questions
Orillia additional dwelling unit questions
How many dwelling units can be permitted on an Orillia residential lot?
Orillia’s current guide allows up to four total dwelling units on a qualifying lot: the principal dwelling plus a maximum of three ADUs. The actual number and arrangement depend on the property, existing dwelling type, zoning, servicing, parking, and all applicable approvals.
Do I need a Zoning Certificate before the building permit?
Yes. The City requires a Zoning Certificate before a residential building permit application. The zoning submission typically includes a site plan and, for a new dwelling, building elevations.
When is a lot grading plan required for an Orillia ADU?
The City’s quick guide says a lot grading plan is required when a new unit involves an addition to the existing dwelling or a detached ADU. It is not required for an ADU created entirely within the existing dwelling when no addition is proposed. Confirm project-specific requirements with the City.
What drawings are typically required for an interior ADU?
The City’s current checklist identifies detailed existing floor plans, proposed ADU floor plans, elevations and details, entrance and exit information, emergency egress window information, existing floor and fire-separation details, and heat-loss and heat-gain information when applicable.
Can an additional dwelling unit be detached in Orillia?
Potentially. Orillia’s current zoning guide permits up to two ADUs in one detached accessory structure on a qualifying lot, subject to the overall four-dwelling maximum and requirements for the structure, yards, height, floor area, access, parking, servicing, grading, and permits.
How are Orillia ADU permit applications submitted?
After obtaining the required Zoning Certificate and completing the permit package, applicants can submit online through Orillia’s e-Permit Public Portal. The City reviews the application and identifies deficiencies, fees, and required inspections.