The Case For Four Unit Zoning

Why Fredericton Needs To Approve Gentle Density City Wide

Since 2018 a wave of cities across the United States have abolished exclusionary single family zoning and legalized three and four unit dwellings across all residential zones. Minneapolis was the first city to enact such zoning reform with its Minneapolis 2040 comprehensive plan.

Here in Canada, the federal government first announced the Housing Accelerator Fund (HAF) in March 2023. In the face of a nationwide housing affordability crisis the intent of the fund is to help cities more quickly increase the supply of housing. One of the base criteria for receiving funding is to legalize up to four dwelling units in all residential zones, creating the impetus for a similar wave of zoning reforms across the country – including in Fredericton.

The city’s proposed zoning amendment passed its first hurdle after being presented to the Planning Advisory Committee (PAC) on February 19, 2025. It will be presented to City Council on March 10.

In this piece I will present the case for why city council needs to approve this amendment. I’m not going to delve into the technical details of the zoning code itself; I’ll do that in a follow-up post. Suffice to say that the broad implication of this amendment is that homes with up to three secondary dwelling units (SDUs) will be legalized in all residential zones city wide.

Why four units?

As I said above, the HAF aims to increase the supply of housing and in turn bring down housing costs. Four unit zoning is just one of many initiatives undertaken by the city as part of its HAF agreement with the federal government. Others include workforce zoning to allow residential development in commercial corridors, developing a master plan for the Doak Road growth node, and various grants to subsidize the creation of more housing.

Fredericton has taken a novel approach in its zoning code for four unit dwellings. Rather than legalizing traditional triplex and fourplex homes it instead focuses on adding secondary units in addition to the primary unit that already exists. Secondary units can take the form of basement apartments, contained within or in an addition on the primary unit, as garden suites, or as a garage suite. While the zoning code does not strictly forbid building four units from scratch, it is structured in a way that makes conversions the more logical choice.

Legalizing four units allows for gentle density and results in more diversity in housing types aside from the typical single family homes and larger apartment buildings that are typical in most neighbourhoods. It gives people the opportunity to move to neighbourhoods that may not have been accessible to them before, and it allows long time residents opportunities to age in place.

Better infrastructure value and lower construction costs

Building new neighbourhoods is expensive. The preliminary cost estimates to build out the Doak Road neighbourhood include $53M in infrastructure for about 3500 homes, or $15,000 per dwelling unit. On top of this come land costs and other fees. Current building costs result in townhouses costing at least $300,000 and single family homes generally cost over $400,000. Even typical apartment buildings are approaching and sometimes exceeding $300,000 per unit for new builds.

By allowing more housing to be built on what are traditionally single family lots, homeowners can create new housing using existing infrastructure on land that they already own. This means that the incremental cost to add an additional unit of housing is much lower. It also means that the cost of maintaining existing infrastructure is spread out across more homes, lowering the tax burden for everyone.

Depending on what form the secondary dwelling unit takes, you can add a unit of housing for between $50,000 and $200,000 rather than $300,000 or more.

Helping first-time buyers enter the housing market

With housing costs having rapidly increased in the last five years it is increasingly difficult for people to enter the housing market. Many people may qualify for a relatively large mortgage on paper but don’t want to be house poor. Secondary dwelling units allow these buyers to rent out a portion of their property and cover some of their housing costs, either by adding the additional unit(s) themselves or purchasing a property that already has them.

It also means that these buyers may have more flexibility in choosing the neighbourhood they want to live in, and not be relegated to only the less expensive neighbourhoods that have fewer services and amenities.

Keeping neighbourhoods family friendly

The “family friendly” argument is often used to oppose zoning reform that allows for more than one dwelling unit on a property. Presumably this means the nuclear family. But changing demographics mean that families are increasingly taking on other forms and we need appropriate housing for those people as well.

Here in New Brunswick we have long had an aging population. This has caused a migration from the smaller communities and rural areas to the cities by seniors looking to live closer to the services they need as they age. People are also choosing to put off having children or not have children at all, and people tend to stay single for longer than they used to as well.

In many cases these people don’t want or perhaps cannot afford a single family home. By allowing the construction of more secondary dwelling units we provide opportunities for these people to live in established neighbourhoods and have access to nearby services and amenities that often don’t exist in the new neighbourhoods built on the periphery of the city.

It also means that when it comes time to downsize from a single family home, there are opportunities to stay in the same neighbourhood. For example, a backyard garden suite could be the ideal type of residence for a senior who wants to have a private space but no longer needs a large home.

Gentle density enables better public transit

It is generally accepted among transportation planners that the minimum density required to support regular bus service is seven dwelling units per acre. While most newer neighbourhoods in Fredericton likely meet this density, thanks to a mix of housing types including row houses and apartments in addition to single family homes, there are large swaths of the city which have a density of around four dwelling units per acre, or even less.

The presence of SDUs allows existing low density neighbourhoods to incrementally increase, particularly in combination with other infill development closing existing gaps in neighbourhoods. This in turn increases transit ridership and can justify increased transit frequency and reduce car dependence which is beneficial to all city residents.

Won’t my neighbourhood rapidly densify?

The short answer is no.

The reality of city wide zoning reforms is that they tend to result in incremental development that is spread throughout the city. Intuitively, we can conclude that more secondary dwelling units will be built in neighbourhoods that are more walkable and are on transit routes, as the appeal of living in a secondary unit is lower the further you get from the city centre.

When the city of Charlottesville VA – a city similar in size to Fredericton – was considering zoning reform it commissioned a “rate of change” study to determine the likelihood of a single family home being redeveloped with additional units. In the zones that would allow three units the study determined a 1.9% rate of change per year, meaning approximately one in fifty properties would have additional units added to it each year. The study also included a caveat that this was likely a higher rate than what would actually occur, since not all lots would actually be able to support three units. The same is true in Fredericton where certain zoning rules regarding lot frontage and lot coverage prevent some lots from having multiple SDUs.

I also spoke with an active developer in Minneapolis and asked him about the effects of the Minneapolis 2040 comprehensive plan I mentioned above. He said that the plan has helped build a lot of new housing but very few are of the 2-4 unit type, partly because of height restrictions that are similar to Fredericton’s.

A crucial aspect to this zoning reform is that other zoning changes that have been enacted, like the ability to put residential buildings in commercial corridors, make it easier to build larger developments. Consequently, developers tend to pursue projects larger than what can be built on lots with existing single family homes. Secondary dwelling units are much more likely to be built by homeowners rather than investors.

Fredericton already has a four unit zoning precedent

Large portions of the town plat already have zoning that allow for four or more units. The current minimum lot size for four units in the TP-4 zone is 720 square metres which is a typical size lot for a single family home. Because many lots downtown are undersized, there’s also quite a few properties that are legal non-conforming because they predate current zoning rules.

Looking at some of the typical blocks in the town plat that allow four or more units, we see a mix of single family and multi family homes. In many cases the multi family homes look like single family homes at first glance. The vast majority of structures in the town plat predate modern zoning codes altogether meaning that these neighbourhoods developed organically over time.

And the town plat arguably has the best character of any area in the city despite this flexible zoning. Home values are also very high in this area, again suggesting that the flexible zoning is not a detriment to living there.

The broader implications

The city of Fredericton’s agreement with the federal government under the Housing Accelerator Fund includes eight different initiatives to increase the supply of housing in the city. Allowing up to four units in all residential zones is a requirement under HAF. That is, if this zoning amendment does not pass, Fredericton loses the $10.3M in funding.

This means that other initiatives would also be canceled, including the various grants being offered to help fund affordable housing units and accessory dwelling units.

But that isn’t all. Four unit zoning is also a requirement for the Canada Housing Infrastructure Fund. That fund has allocated $150.5M to New Brunswick and only Moncton, Saint John, and Fredericton are eligible to apply for those funds. This is potentially tens of millions of dollars for the city and would be crucial for building out the infrastructure for the Doak Road growth area.

Saying no to four unit zoning is saying no to money that is helping build affordable housing and the money that will allow the city to grow further. Without this money, housing becomes more difficult to build, which means less gets built and housing costs continue to rise, and with them so do our property tax bills.

There are further downstream consequences as well. Education, healthcare, and technology make up a significant portion of our economy and the success of these industries relies on attracting talent from outside the region. But as housing costs rise it becomes more difficult to recruit employees and these industries suffer, resulting in lost wages and lower economic output.

In conclusion

By allowing more dwelling units on lots traditionally intended for single family homes we make it easier and less expensive to add units to the housing market. While allowing four units in all residential zones will not by itself solve the housing crisis, it is one of the tools that helps, and we should use all the tools available to us to solve the problem.

If you’re a resident of Fredericton and agree, please consider contacting your councillor and voicing your support or attend the council meeting on March 10. As always, the negative voices are currently the loudest and I think it’s important to make it clear to council that there are also those of us in favor of zoning reform that will provide residents of Fredericton with affordable, diverse, and sustainable housing.