Toronto's free fourplex and sixplex plans: what they mean for cost
Toronto has released free pre-approved multiplex designs. We look at what that changes for homeowners and the costs of related projects.
Toronto's new free multiplex plans can save you design work, but they don't remove the main costs of building: construction, permits, a design professional and the services that go into each unit. According to Construction Canada, the City has added fourplex and sixplex designs to its Pre-Approved Building Plans Program.
What the City has announced
The program already covered garden and laneway suites. The new designs add fourplexes and sixplexes, which the City describes as suited to its residential neighbourhoods. Each comes in a wide and a narrow version, covering four of the city's most common lot sizes.
Key points, as reported:
- The designs are free to download at toronto.ca/PreApprovedPlans.
- They were developed by LGA Architectural Partners after a City request for proposals.
- They are meant to comply with the Ontario Building Code and zoning rules for the buildings themselves.
- The City says accessibility, climate resilience, cost and ease of construction shaped them.
- You still need a building permit, and the City must confirm the project complies with the relevant laws.
- You still need a qualified design professional for the site-specific parts of the application, such as where the building sits on the lot.
The catch: changes end pre-approval
The report says that modifying a pre-approved design removes its pre-approved status. Changes to mechanical systems, including HVAC or plumbing, also count. If you go that route, you follow the regular building permit process.
That matters for budgeting. A heat pump, a different water heater or a rerouted drain can mean extra design and review time. Settle your mechanical choices before you commit to a plan.
According to the same report, Toronto permits fourplexes city-wide, while sixplex permissions vary by location. Projects that meet the zoning requirements can apply directly for a building permit without going to the Committee of Adjustment.
What it means for costs
The plans cut design costs, but we don't price whole multiplex builds. We can show you what some of the related work costs. Our figures are before GST/HST and come from labour hours × local rates plus materials, checked against market prices and real quotes.
Heating and cooling. A ducted heat pump typically costs $12,000 (range $9,350 – $15,600). A ductless system for several rooms is typically $9,950. See our [heat pump guide](Heat pump installation) for options. Both would count as mechanical changes if you alter a pre-approved plan.
Water heating. A water heater swap typically costs $2,500. See Water heater replacement.
Wiring and charging. Rewiring an existing house typically costs $10,500, see House rewiring. An EV charger usually runs $1,800, see EV charger installation. In Ontario, a licensed electrical contractor files electrical permits and notifications with the Electrical Safety Authority.
Basement work. If you're converting or adding units on an existing lot, water protection matters. Basement waterproofing typically costs $10,500, see Basement waterproofing. Toronto's Basement Flooding Protection Subsidy Program offers up to $6,650 per property, with each item covered at up to 80% of the invoice. That includes sump pumps, backwater valves, storm sewer disconnection and a plumbing assessment. It applies to eligible work completed on or after 12 Nov 2025. Contractors need a valid City of Toronto business licence, and a backwater valve needs a building permit and inspection.
Exterior work. Roofing, siding and windows will all feature in any project. A shingle roof typically costs $9,000, see Roof replacement. Windows are typically $5,400, see Window replacement.
How to use the plans
- Check zoning first, especially for a sixplex, since permissions vary by location.
- Pick a plan that fits your lot width and avoid changes, so you keep pre-approved status.
- Budget for a design professional, a building permit and licensed trades.
- Get several itemized quotes. Our quote checker ("is my quote fair") lets you compare what you're offered against our live figures.
Remember that GST/HST applies to renovation work on top of our figures. Plumbing, gas and electrical work needs licensed trades and usually a permit.
The free plans lower one barrier. The rest of the budget still depends on your lot, your contractors and how closely you stick to the City's designs.