Oshawa zoning for small homes

Backyard suite

A separate home in the yard of a house: garden suite, laneway suite or coach house, including prefab, modular or container units used this way.

Allowed · Oshawa’s term: “accessory apartment in an accessory building (garden suite)”

One accessory apartment is permitted in a building accessory to a single detached, semi-detached or street townhouse dwelling in the R1, R2, R3, R5, OSR-A, OS-ORM, AG-A, AG-B and AG-ORM zones, up to three units per lot in total. It is subject to the accessory building size, height and separation rules and to hazard-land and setback restrictions. [1]

Maximum size: All accessory buildings combined (R1-A to R1-F, R2, R3, R5): the most restrictive of 10% of lot area (8% for any single building), 100% of the main building's lot coverage (75% for any single building), or 60 m² ground floor area. R1-G/R1-H: 8% of lot area, 100% of main building coverage, or 90 m². In R1-G, R1-H, OSR-A, OS-ORM and AG zones the apartment itself is capped at 60 m² or 100% of the main dwelling's floor area, whichever is less (ss.5.1.2, 5.12.1(a)) [2]
Maximum height: R1-A to R1-F, R2, R3, R5: lesser of 4.5 m or main building height, up to 6.0 m if set back at least 6.0 m from the rear lot line (not exceeding main building). R1-G/R1-H: lesser of 5.0 m or main building height, 6.0 m with a 6.0 m rear setback. Agricultural zones: 6.0 m (s.5.1.3) [2]
Setbacks: Minimum 0.6 m from interior side and rear lot lines; 30 m from a railway right-of-way; 14 m from the Highway 401/407 East property line; 7.0 m from a gas or oil pipeline corridor; not in hazard lands [2]
Separation from house: At least 3.0 m from the main building; in R1-G, R1-H, OSR-A, OS-ORM and AG zones, no more than 15.0 m from it [2]
Number allowed: One accessory apartment in the house plus one in an accessory building (or two in the house and none in an accessory building); maximum 3 dwelling units per lot [2]
Parking: One additional parking space per accessory apartment, in addition to the dwelling's minimum requirement (s.5.12.2) [2]
Where allowed: R1, R2, R3, R5, OSR-A, OS-ORM, AG-A, AG-B and AG-ORM zones; not where the main dwelling is only an interim 'h' holding use [2]
Approvals: Building permit; minimum 0.81 m unobstructed walkway from the street to the entrance [3]

Ontario-wide rule

Ontario law stops municipalities from banning one residential unit in a building ancillary to a detached house, semi-detached house or rowhouse on a parcel of urban residential land, as long as the lot has no more than three units in total. Municipalities still set most other zoning rules, but provincial law limits parking requirements, minimum unit size, lot coverage and separation distances. These units are also exempt from development charges and parkland dedication. [4][5][6]

Tiny home on a foundation

A small house as the main home on its own lot. The key rule is any minimum dwelling size.

Allowed · Oshawa’s term: “single detached dwelling”

Table 6.2 for the R1 zones sets lot frontage, area, yards, coverage and height but no minimum dwelling floor area. Minimum floor areas appear only in a few site-specific exceptions.

Minimum dwelling size: None in the standard R1 zone regulations (Table 6.2); minimum lot area ranges from 270 m² (R1-E) to 6,000 m² (R1-H) [2]

Ontario-wide rule

Ontario law sets no minimum total size for a house that is the main dwelling. The Building Code sets minimum room areas, so the smallest compliant dwelling is roughly 17.5 m² by the Province's own estimate. Municipalities may still set minimum floor areas for main dwellings in their zoning by-laws. The provincial ban on minimum sizes covers only additional residential units. [4][7][8][9][10][11][12]

Tiny home on wheels or park model

Living full-time in a tiny home on wheels or a park model home.

Not allowed · Oshawa’s term: “mobile home / trailer”

The definition of single detached dwelling excludes mobile homes, and no zone lists mobile homes or mobile home parks as a permitted use. Trailers are also prohibited from being used as accessory buildings in any Residential Zone. Campgrounds are defined only for temporary accommodation.

Where allowed: None: 'SINGLE DETACHED DWELLING' ... 'does not include a mobile home'; mobile home is not a listed use in any zone [2]
Approvals: s.5.1.1(2): trailers, truck bodies and school portables 'are prohibited from being used as accessory buildings to residential uses in any Residential Zone' [2]

Ontario-wide rule

Ontario has no single rule for living full-time in a tiny home on wheels. A unit on wheels can count as a 'building' that needs a permit and must meet the Building Code once it stays in one place, is hooked up to services or is anchored. Park model trailers are recognized only as seasonal recreational buildings. Municipalities may allow a portable garden suite under a temporary-use by-law for up to 20 years, with extensions of up to 3 years each. [12][7][4][9][8]

Bunkie or sleeping cabin

A small sleeping building with no kitchen, usually beside a cottage or house.

Not allowed · Oshawa’s term: “accessory building”

The by-law defines an accessory building as 'a detached building not used for human habitation', with the only exception being one that contains a lawful accessory apartment. A sleeping-only cabin is therefore not permitted in any zone, including the agricultural and rural open space zones.

Kitchen: Only a full dwelling unit (accessory apartment with toilet and cooking facilities) may be occupied in an accessory building [2]

Ontario-wide rule

Ontario law has no rule written specifically for bunkies or sleeping cabins. Whether one needs a building permit depends on the Building Code Act's definition of 'building' and the Code's shed exemption. That exemption covers only storage-use sheds, so it does not cover a structure used for sleeping. Municipal zoning rules for accessory buildings still apply. [9][7][4][13]

Official links

Last confirmed October 2026.

Notes and caveats

The City's accessory apartments web page still gives the older accessory-building limits: 8% of lot area, 50% of the house's coverage, and 4.5 m height. The August 2026 by-law consolidation, amended by By-law 59-2026, now allows 10% of lot area (8% per building), 100% of main building coverage (75% per building), and up to 6.0 m height with a 6.0 m rear setback. The JSON uses the by-law text. Accessory apartments that existed on February 19, 2025 in OSR/AG zones may be up to 70 m². The by-law has generic Temporary Use Zones (s.3.12) but no garden-suite-specific temporary use provision.

Sources

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Oshawa zoning for small homes

Backyard suite

Ontario-wide rule

Tiny home on a foundation

Ontario-wide rule

Tiny home on wheels or park model

Ontario-wide rule

Bunkie or sleeping cabin

Ontario-wide rule

Official links

Sources

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