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↓ What are additional residential units (ARUs)?
↓ ARUs policies and regulations update

In an effort to increase housing options and supply throughout the province, the provincial government has recently made some changes to the Planning Act, permitting two additional residential units (ARUs) on an urban residential lot containing a detached house, semi-detached house or townhouse. This would allow up to three residential units in total on a residential lot with municipal water and sewage services.

The Town is in the process of reviewing and updating its policies and regulations regarding additional residential units to align with the updated Planning Act. To get involved and share your feedback to shape and inform the updates to the Official Plan policies and zoning by-law regulations, please participate in our surveys and provide feedback on Let’s Talk Milton.

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What are additional residential units (ARUs)?

ARUs, as defined by the Planning Act, refer to a second and a third residential unit in addition to a primary residential unit, for a total of three units, on a residential lot containing a detached house, semi-detached house or townhouse. 

ARUs require a set of self-contained rooms containing kitchen, sleeping and bathroom facilities intended for the exclusive use of the unit. ARUs must adhere to Ontario Building Code and Fire Code requirements. 

ARUs are also referred to as second units, secondary suites, accessory dwelling units, basement apartments, coach houses, laneway houses, garden suites, tiny homes, granny flats, in-law apartments or nanny suites.

ARUs policies and regulations update

The Town is currently reviewing its Official Plan policies and zoning by-law regulations as it relates to ARUs.  Please see more details below regarding urban and rural areas.

Urban areas

The Town of Milton’s existing zoning by-law regulations in the urban area only permitted one additional residential unit (termed “accessory dwelling unit” in the by-law) within a detached house or a semi-link house.

In accordance with the requirements of the Planning Act, on residential lots that have municipal water and sewage servicing, Milton’s Zoning By-law 016-2014 for the urban area will be updated to:

  • Permit three units on each lot, including the primary residential unit and two additional residential units, where:
    • All three units may be located within a detached house, semi-detached house or townhouse, OR
    • Two units may be located within a detached house, semi-detached house or townhouse and one unit may be located within an accessory building or structure on the lot; and
    • Require not more than one off-street parking space for each additional residential unit. (Updated: the Province of Ontario’s Bill 97 clarifies that the primary residential unit can be required to have more than one parking space.)

The zoning by-law for the urban area will also be reviewed and updated in consideration of municipal concerns such as health and safety, stormwater management, neighbourhood character and impacts on adjacent properties.

The Town’s Official Plan will be reviewed and may be updated to provide high-level policies regarding additional residential units.

Rural areas

The provincial as-of-right permissions for additional residential units do not apply in Milton’s rural areas. Significant portions of Milton’s rural areas are within the Greenbelt and the Niagara Escarpment, which include provincially protected environmental and agricultural lands.

In consultation with the Province, staff will undertake a review to examine if the Town’s policies and regulations may be updated to better address the needs of the rural community for additional residential units.