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 2004, and that a review of it has been underway since 2010. The by-law itself has a disclaimer noting that elements of it may no longer be accurate; as such, please consider this a double disclaimer, that the outline offered for you here is for general orientation to the matter only, and any details should be confirmed with the planners.

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 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. A tiny home ADU is more specifically defined here as a Garden Suite, which “is designed to be portable”, meaning that a tiny home on wheels would meet this definition.
  
• A tiny home as a primary dwelling might be considered a single-detached home, whose definition here explicitly includes a modular home and a double-wide mobile home. However, Cobourg still requires a minimum size in each of their residential zones (see below), making it nearly impossible to have a truly tiny home as a primary dwelling.
  
• The by-law defines mobile homes in a way that could include a tiny home, including one either on wheels or on a foundation; but also defines a modular home separately, explicitly stating that it is a prefabricated structure on a foundation and does not include a single-wide mobile home. Depending on its construction, your tiny home could fit either category. More important is how it is set up, i.e., the distinction between being a Garden Suite (on wheels), or just being an accessory dwelling (on a foundation).
  

General Zoning Information

Some uses are permitted or prohibited in all zones. In this section it makes explicit notice that mobile homes are not allowed for any purpose in any zone (5.20) unless that zone explicitly allows for it. For example, in a residential zone a double-wide mobile home can be used as a dwelling if it is placed on a foundation. Helical piers are not considered a foundation in this zoning by-law. Check with your tiny home provider, as some of them promote the use of helical piers over slab foundations.

A “Garden Suite” in any zone is subject to the following (section 5.25):

GARDEN SUITE
Garden Suite shall only be permitted with the following regulations:
i) The Garden Suite is to be used by a senior member of the owner of the residence. No portion of the subject Garden Suite shall be made available for rent by the general public.
ii) A temporary use by-law will be required as approval by Council.
iii) As a condition to passing a by-law authorizing the temporary use of a garden suite, Council may require the owner of the suite or any other persons to enter into an agreement with the municipality

So defined, a Garden Suite is intended to create a space on your property for your aging parents, and it requires specific council approval on a temporary basis, rather than as a permanent structure that could be used by anyone.

Parking requirements are 2 spaces for a detached home in any zone (6.1.1.i), unless your home is in the “Reduced Parking Requirement Area” downtown (6.1.1.vi), in which case it is reduced to 1 space. Further, if you’re in this area it’s possible to make an agreement with council to pay cash in lieu of parking.

Parking spaces need to be accessible to the dwelling unit, so for example, an inside townhouse unit which spans the entire width of the lot can’t have a driveway in the front yard and an ADU in the backyard, or the person in the ADU would have to walk through the main house to get to their home.

Residential Zones

Cobourg has five residential zones:

• Residential 1 Zone (R1), which permits “one single detached dwelling on one lot” and accessory uses (7.1.3) – note that accessory uses includes up to one detached ADU, by virtue of a provincial statute.
  
  • R1 zoning requires a minimum of 1,200 sq ft of floor space in the primary dwelling, so you are unable to have a tiny home as the primary dwelling in an R1 zone.
    
  • Section 7.1.16 explicitly prohibits having anyone dwell in an accessory structure; but the provincial statute (section 16.3 of the Planning Act) should override this prohibition if you want to add a detached ADU to your property.
    
  • Section 16.3.2 of the Planning Act states that “No official plan may contain any policy that provides for a minimum floor area of a residential unit referred to in subsection (3).” This means that the minimum size of your ADU is set by the Building Code, not by local by-laws. This does not apply to the primary dwelling, only to ADUs.
    
  • Accessory buildings in an R1 zone cannot be closer to the front lot line than the primary building, so an ADU 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 (7.1.16), and needs to be accessible via the driveway.
    
• Residential 2 Zone (R2), which has very similar provisions to R1 zoning except at a smaller scale, with smaller lots and a minimum primary building size of 860 sq ft. So still no tiny homes as the primary structure in R2 zoning.
  
• Residential 3 Zone (R3) allows for semi-detached (two units divided vertically, i.e., sharing a wall) and duplexes (two units divided horizontally, i.e., one upstairs one downstairs) in addition to single detached homes. The lot area per unit is again smaller than in the R2 zone, and the minimum house size is smaller too, with a single detached in R3 zoning having a minimum size of 750 sq ft. However, semi-detached or duplex units have different minimum sizes, depending on the type of housing unit: a “bachelor” unit in a duplex or semi-detached can be as small as 300 sq ft, a one-bedroom as 450 sq ft, and a two-bedroom unit as 600 sq ft. This is where “tiny home living” can finally apply in the primary unit!
  
  • As in the other R zones, the by-law states that detached accessory structures are not for human habitation, but this part of the by-law is overruled by recent changes to the Planning Act (see above), so you can have a detached ADU on an R3 zoned lot.
    
  • Parking requirements for semi-detached and duplex units are still 2 spaces per dwelling unit (6.1.1.i)
    
• Multiple Residential 4 Zone (R4) allows for semi-detached dwellings, townhouses (a row of connected houses divided vertically), duplexes, triplexes, fourplexes, and multi-residential (i.e., apartment buildings). It is not allowed to have a single-detached dwelling in R4.
  
  • The minimum size of lot is again smaller than in the R3 zone, allowing for small lots for semi-detached and townhouse units in which each unit has its own land. For those looking to build a tiny home village, it’s theoretically possible to have tiny home townhouses, as each lot would only have a minimum frontage of 6.5m (21 ft). Each interior unit would be connected on both sides to its neighbours, which is a shift from the typical emphasis in tiny home culture on independence and more outdoor living, but nonetheless it’s theoretically possible here.
    
  • The minimum lot size for a semi-detached unit on its own lot requires 9m (30 ft) of frontage, or alternatively you can have the whole semi-detached dwelling (both units) on the same lot with a minimum of 18m (60ft) of frontage. It’s possible to have semi-detached tiny homes each with their own lot, sharing one wall along the lot line; or two units together on one lot, either as semi-detached or a duplex (if you can find a two-story tiny home).
    
  • The minimum size for units in R4 zoning depends on the type of dwelling: a “bachelor” unit can be as small as 28 sq m (300 sq ft), a one-bedroom unit 42 sq m (450 sq ft), and a two-bedroom 56 sq m (600 sq ft), and so on (see 10.1.8 for the table). Interestingly, there’s a slightly smaller version of each category for senior citizens.
    
  • Accessory buildings are explicitly not allowed to be used for human habitation in Cobourg, but again, recent changes to the Planning Act overrides this. Provided your ADU is not closer to the front lot line than the primary dwelling, you should be allowed one. The language elsewhere in the by-law suggests that the primary dwelling needs to be larger than any accessory structure, so make sure you connect with the Planners to plan accordingly.
    
  • With all of that in mind, a “tiny home village” concept could consist of four tiny homes, two of which are connected as semi-detached each with a slightly smaller ADU, over two lots. The requirement that ADUs have access to a driveway would seem to prevent a “tiny home village” based around a row of tiny townhouses having their own ADUs in the backyard, since only the end units would be able to access the backyard from the street/driveway. (Note that this would be true of larger townhouses too!)
    
• High Density Residential 5 Zone (R5) is only for townhouses or apartment buildings, with a minimum frontage of 6m for townhouse lots. The minimum unit sizes are the same as for R4 zones, and the same conundrum for ADUs applies: interior townhouse units couldn’t provide outside access to the backyard, since their unit necessarily takes up the whole width of the lot, so backyard ADUs would have no street access. So in theory only end units of townhouse developments could have ADUs.

While Cobourg does allow accessory uses in Commercial zones, it explicitly forbids dwelling in accessory buildings throughout the zoning by-law. The recent provisions in the Planning Act allow accessory dwelling units in all residential zones, but not commercial. So while a commercial building can have an apartment upstairs, it can’t have one in a backyard ADU.

Cobourg does have a Rural (RU) zone, which allows a single detached dwelling as an accessory use to Agricultural use of the property. That means the first dwelling on the lot would be an accessory dwelling (see 22.1.14). The Planning Act‘s requirement of allowing ADUs in all residential zones would not apply here. That said, there appear to be no minimum sizes for this detached dwelling, so it could be tiny, provided it was on a concrete foundation instead of wheels so as to meet the “modular housing” definition rather than the “Garden Suite” definition (which can be on wheels but is much more stringently regulated, see above).