What Is House Hacking?

House hacking is the practice of buying a residential property that has — or can have — rental units, living in one portion yourself, and collecting rent from tenants in the other unit(s) to offset or eliminate your housing costs.

The simplest version is buying a duplex, moving into one unit, and renting the other. A more aggressive version is buying a triplex, living in one unit, and having two rent-paying tenants cover your entire mortgage and expenses while you build equity for free.

In markets like Ottawa, Hamilton, or smaller Ontario cities where duplex and triplex prices are still reachable for first-time buyers, this strategy makes a significant dent in housing costs — and can completely eliminate them in the right deal.

Property Types That Work

Property TypeHouse Hacking PotentialNotes
Duplex (2 units)High — classic house hackYou live in one, rent the other. One rental income stream to offset your mortgage.
Triplex (3 units)Very high — two rental incomesTwo tenants paying rent often covers the entire mortgage on properly-priced deals.
Single-family home with legal basement suiteModerate to highConfirm the suite is legal — illegal suites carry risk and can't always be rented.
Single-family home with potential to add suiteLower — requires capital and permitsPossible but adds cost and timeline risk before you receive rental income.
Fourplex (4 units)Highest potential — three rental incomesMay qualify for owner-occupied CMHC financing up to 4 units. Note: 3–4 unit properties require a minimum 10% down payment, not 5%.

How the Math Works in Ontario

The core calculation: take the total monthly cost of owning the property (mortgage payment, property taxes, insurance, utilities you pay, maintenance reserve) and subtract the rental income from tenant units. What remains is your effective housing cost.

Example — Ottawa duplex: Purchase price $650,000. With 10% down and a 25-year amortization at ~5.5%, your monthly mortgage payment is approximately $3,700. Property taxes and insurance add ~$700/month. Total cost: ~$4,400/month. One unit renting at $1,800/month brings your net cost to $2,600 — cheaper than most Ottawa one-bedroom apartments.

Run the full numbers with Ontario-specific costs before buying. The Ontario Rental Property Analyzer models land transfer tax (including the GTA surtax), CMHC insurance, Ontario-specific maintenance costs, and gives you a clear monthly cash flow picture for mixed-use owner-occupied properties.

Financing Advantages

One of the most significant advantages of house hacking in Ontario is the financing structure for owner-occupied properties with up to four units.

Property TypeMinimum Down Payment (Owner-Occupied)
1–2 unit property under $500K (owner-occupied)5% on first $500K
1–2 unit property $500K–$1,499,999 (owner-occupied)5% on first $500K + 10% on remainder
3–4 unit property (owner-occupied) under $1.5MMinimum 10% — CMHC insured (as of Dec 15, 2024, the price cap is $1.5M)
Pure investment property (non-owner-occupied)Minimum 20% — no CMHC insurance available

The owner-occupied advantage: If you live in the property, you can buy with as little as 5% down and access CMHC mortgage insurance — which is not available for pure investment properties. This dramatically lowers the capital required to get into real estate investing. The requirement is that you occupy one of the units as your principal residence.

Lenders will also often factor rental income into your mortgage qualification calculations for owner-occupied multi-unit properties, which can increase your borrowing capacity.

Ontario RTA Rules That Apply

Living in your investment property doesn't exempt you from the RTA. Your tenants have the same rights as any other Ontario tenant, and you have the same obligations. A few rules are particularly relevant for house hackers:

Tax Implications

House hacking creates a mixed-use property situation for CRA purposes. The rental portion of the property generates taxable income that must be reported on your T776, while the portion you occupy is your personal principal residence.

Key tax considerations:

What to Look For When Buying

Not every duplex or multi-unit property makes a good house hack. These are the factors that determine whether the math works:

The Real Risks

House hacking is one of the most accessible real estate strategies in Ontario, but it isn't without risk. The honest assessment:

Ontario Rental Property Analyzer

Model any Ontario property purchase — duplex, triplex, or single-family with suite. Calculates your actual monthly cost after rental income, Ontario LTT, CMHC insurance, DSCR, and 5-year equity growth. CA$45.99.

Get the Rental Analyzer — CA$45.99 →

This article is for informational purposes only and does not constitute legal, financial, or tax advice. Real estate investing carries risk. Always consult a licensed mortgage professional, accountant, and lawyer before purchasing a property.