Multiplex costs and timelines in Toronto: how to plan your budget

“How much does a multiplex cost?” is the first question almost everyone asks. The honest answer is that it depends on the house, the lot and the scope. What we can do is show you how a budget is built, so you can compare quotes on the same basis.

Hard costs vs. soft costs

Hard costs are the physical work: demolition, foundations, framing, mechanical, electrical, plumbing, finishes and site work.

Soft costs are everything else: design, engineering, surveys, permits, legal fees, financing costs, insurance and a contingency.

Budget template by stage

Typical stages, time and cost (template)TODO: verify

Stage	Typical time	Cost
Feasibility study	[x] weeks	[$ placeholder]
Design & engineering	[x] months	[$ placeholder]
Zoning review & permits	[x] months	[$ placeholder]
Committee of Adjustment (if needed)	[x] months	[$ placeholder]
Construction: conversion	[x] months	[$ placeholder]
Construction: new build	[x] months	[$ placeholder]
Contingency	—	[x]% of hard costs

What moves the budget most

• Basement work. Lowering a basement or underpinning is often the largest single line item in a conversion.
• Servicing upgrades. Larger water and sewer connections, and electrical service upgrades.
• Fire and sound separation. Required between units, and harder to retrofit in older houses.
• Finishes. Rental-grade and owner-grade finishes can differ a lot in cost.

What moves the timeline most

• Whether you need a minor variance
• How complete the drawings are when you apply for a permit
• Long-lead items such as windows, electrical service and utility connections

Next steps

Our feasibility study turns this template into a real budget for your property.

Sources

• City of Toronto: Multiplex housing TODO: verify
• City of Toronto: Development charges FAQ TODO: verify

Last updated: November 11, 2026