Duplex vs fourplex as an investment in Canada
Both finance as residential 1–4 unit files at the qualifying rate. The fourplex usually wins on per-door basis and vacancy resilience; the duplex wins on entry price, buyer pool at exit, and owner-occupied leverage. The decision is basis and downside, not door count.
Financing is the same file
One to four units is a residential mortgage either way: 20% minimum down on a pure rental, 25-year amortization typical, and DSCR read at the qualifying rate. Owner-occupy one unit and insured financing opens at as little as 5–10% down — a duplex you live in is often the cheapest leverage in Canadian real estate. Neither building touches MLI Select; that starts at five units.
Where the fourplex wins
Per-door basis: four doors on one roof, one furnace bill, one lot — a fourplex usually prints a lower price per door and a higher cap than a duplex on the same street. Vacancy math: one empty unit is 25% of gross, not 50%. A duplex with a vacant unit is half-dark and usually cash-flow negative; a fourplex absorbs the same vacancy and keeps paying the mortgage. On the Ottawa screen this desk runs, small multifamily caps sit around 4.3%–5.6% with fourplexes at the healthier end.
Where the duplex wins
Entry and exit. The cheque is smaller, the qualifying hurdle is lower, and at sale a duplex trades to owner-occupiers as well as investors — a deeper buyer pool that supports price even when cap rates soften. Duplexes also dominate the house-hack path: live in one unit, rent the other, refinance later. Management is two leases, not four, which matters if you are self-managing your first building.
How to decide
Underwrite both on the same page: ask per door against the city band, DSCR at the qualifying rate, cash-on-cash on the real cheque. If you need the property to carry itself through a vacancy, the fourplex's math is more forgiving. If the constraint is your down payment or you intend to live in it, the duplex is usually the entry. A triplex is the compromise both camps ignore.
Questions
- Is a fourplex a better investment than a duplex?
- Usually on the numbers — lower per-door basis, higher cap, and one vacant unit costs 25% of gross instead of 50%. The duplex wins on entry price, owner-occupied leverage, and resale to a deeper buyer pool.
- Is financing different for a duplex vs a fourplex?
- No. Both are residential 1–4 unit files: 20% down minimum as a rental, stress-tested at the qualifying rate. Owner-occupying a unit can cut the down payment to 5–10% with insured financing on either.
- Can I house-hack a fourplex?
- Yes — owner-occupied insured financing covers 1–4 units, so a fourplex house-hack gets the same low-down-payment path as a duplex. The building still has to clear the stress test with rental offsets.
- What about a triplex?
- Same residential file, and often the sweet spot: better vacancy math than a duplex, smaller cheque than a fourplex. Screen it on per-door basis and the qualifying-rate DSCR like everything else.
Screen duplexes and fourplexes
Analysis for information only. Not lending, tax, legal, or investment advice. Confirm current CMHC and OSFI rules with a licensed advisor.