The Community Social Planning Council has produced a Toolkit for municipalities called Local Government Levers for Housing Affordability, with funding from CMHC. The Toolkit, which can be downloaded here, is particularly useful for smaller municipalities that may not have the resources to do a desktop review for policies or tools to use in supporting affordable housing.
There are three groups of levers mentioned: zoning and development policies, financial tools, and tools for greater production and protection of affordable housing. The first category may be the most familiar to planners, including inclusionary zoning, streamlined processing of applications, and incentivizing secondary suites, but also newer tools like rental-only zoning. Multi-family zoning and elimination of parking minimums are not new, but increasingly being applied in Canadian cities (the former in Toronto and Victoria, the latter in Vancouver, Victoria, and Edmonton). Ontario municipalities are undergoing comprehensive reviews to determine ways to streamline development processes (e.g. Mississauga now has an online system for approving development applications and building permits), and in BC, local governments no longer need to hold public meetings for amendments to local zoning by-laws if they are consistent with the Official Community Plan. Financial tools include waiving fees and taxes, density bonuses, amenity contributions, and affordable housing reserve funds–most of which are well known to Canadian planners.
Protection of affordable units is the weakest link identified in my previous work on rental housing policies in Canadian cities. Condo conversion bylaws are the most widespread tool, and they are not that rigorous–Toronto just passed a bylaw regulating rental demolition or conversion of more than six units. A few municipalities have tenant assistance policies to prevent eviction, provide compensation if a tenant has to find a new unit, and provide a right of first refusal (e.g. Vancouver, Victoria, Burnaby). Land and housing acquisition (of existing affordable units) is being undertaken by a few municipalities, including Halifax.
There’s also a great list of existing resources at the end of the document. Check it out if you work at the local municipal level!