Tiny Homes Northumberland

Cobourg is the only fully-urban municipality in Northumberland County, known for its beaches, historic Victoria Hall, and being the county seat for Northumberland.

Cobourg’s planners have been open to tiny homes as ADUs for several years, and are happy to work with residents to navigate the process and any necessary minor variances from zoning. The following should be helpful in orienting you to what that conversation might entail, so you can go in prepared.

Note that this zoning by-law was last updated in 2025, the culmination of a review process that started in 2010! That shows some of the complexity of the planning process, and the forethought that needs to go into setting rules across an entire municipality.

You can find out which zone your property is in by finding it on the maps, here.

Zoning Definitions

• A tiny home used as an ADU (here referred to as Additional Residential Unit, or ARU) would be considered an “Accessory Building or Structure” by these definitions, with “Accessory” meaning “subordinate to” a main use – i.e., there still needs to be a primary dwelling that is clearly the primary dwelling.
  
• There is now a specific definition for ARUs that specifies that it can be within the same building OR on the same lot as the primary dwelling, and can be a modular home dwelling.
  
• A Garden Suite is defined here as specifically “designed to be portable”, meaning that a tiny home on wheels would meet this definition.
  
• There’s a specific definition here for a modular dwelling, which explicitly includes having a permanent foundation.
  
• The definitions also include reference to shipping containers, which are prohibited (under 4.1.1 h in General Provisions) to be used for dwellings unless specifically authorized in the zoning. I don’t see anywhere that it is authorized, so be sure to clarify before purchasing a modular home that uses a shipping container as its frame.
  
• The by-law defines mobile homes with reference to specific CSA standards for their manufacture. It also defines modular homes in a way that specifically excludes mobile homes. Shipping containers and mobile homes are explicitly not considered to be accessory structures unless otherwise permitted in the by-law (and they are not otherwise permitted anywhere in the by-law).
  

General Zoning Information

Some uses are permitted or prohibited in all zones.

Section 4.3 lays out everything you need to know about ARUs in every zone:

• What types of primary dwelling can have an ARU
  • single detached, semi-detached, or street townhouse
• What combination of ARUs is allowed
  • Two total
  • Either one detached from the primary dwelling and one inside the primary dwelling;
  • OR two inside the primary dwelling
• Whether a laneway is required for access
• Municipal water and sewer hookups are required where available
• Properties that prohibit ARUs
  • Environmental Constraint zone, or flood plain
  • Lots containing shared housing, group homes, or B&Bs
• Regulations specific to ARUs that are within the primary dwelling, or that are detached from the primary dwelling

Parking requirements are laid out in a table in 5.4:

• 2 parking spaces for a detached or semi-detached dwelling
• 1 parking space for a modular dwelling
• No additional parking space for a first ARU, and 1 additional parking space for a second ARU

So a single- or semi-detached home with a basement suite AND a backyard tiny home would require three total parking spaces.

Residential Zones

Cobourg has five residential zones:

• Residential 1 Zone (R1), which permits one single detached dwelling on one lot and accessory uses – note that accessory uses includes up to one detached ARU.
  
  • Accessory buildings in an R1 zone cannot be closer to the front lot line than the primary building, so an ARU would have to be beside the primary dwelling (at least 1m from the side lot lines) or in the back yard (at least 1m from the rear lot line). Either way it must be at least 1.5m from any other building on the lot.
    
• Residential 2-3 Zones (R2-R3) have very similar provisions to R1 zoning except at smaller scales. R2-R3 zones allow for semi-detached dwellings in addition to single detached.
  
• Residential 4-5 Zones (R4-R5) allow for various configurations of townhouses and apartments. These zones still allow for ARUs, but not in combination with apartment buildings, only with townhouses.

There’s special zoning for New Amherstville (Part 7), with three zones (NR1 and NR2 for residential zones, and NMU for “mixed use”, which is to say, a combination of residential and commercial). All three of these zones allow for single-detached and semi-detached dwellings and ARUs, the same as R1-R3 zones above, provided they’re on the same lot as a single- or semi-detached or street townhouse; and NMU also allows for apartments and Accessory Dwelling Units, which is an ARU attached to a commercial building (so you can have dwellings above a shop).

Finally, there are Cobourg East Zones (section 8), with Residential 1-3 and Mixed Use. ARUs are allowed in all of these zones, but only on lots where the primary dwelling is a single- or semi-detached or street townhouse.

Commercial Zones

The new Zoning By-Law allows Accessory Dwellings in all commercial zones! Accessory dwellings require 1 parking space per unit, and are otherwise not exhaustively defined. If you’re looking to add residential units to your commercial property, be sure to talk to municipal staff to cast a vision and discover any possible limitations.