If you already own your home, you might be sitting on a hidden asset that could help you grow your wealth: equity. For many New Zealanders, the quickest path to buying an investment property isn't saving another deposit-it's using the equity in the home they already own.
What is Home Equity?
Equity represents the difference between your home's current market value and the amount you still owe on your mortgage.
Example:
- •Home value: $900,000
- •Mortgage balance: $500,000
- •Available equity: $400,000
Banks typically permit borrowing up to 80% of home value. Usable equity calculation: ($900,000 × 80%) − $500,000 = $220,000 usable equity, which could serve as an investment property deposit.
How Much Equity Do You Need?
Investment properties typically require a 30% deposit, though new-build properties may allow 10%. For a $700,000 property requiring a $210,000 deposit, existing home equity of $180,000 gets you most of the way there.
How Do You Access That Equity?
Two main approaches exist:
1. Top-Up on Existing Mortgage - Increase your current mortgage to release equity for the new purchase deposit.
2. Cross-Collateralisation - Both properties secure a single lending arrangement. This offers convenience but carries risk-problems with one property could affect both.
What Will the Bank Look At?
Beyond equity availability, banks assess your ability to service the debt. They evaluate whether your income (including potential rental income) can support the new lending. Expected rental income is typically scaled at 65–80% to account for vacancies and expenses.
Benefits of Using Equity
Risks and Considerations
Should You Use Equity to Invest?
Consider these questions:
- •Can you afford payments if rental income drops or rates rise?
- •Does the area demonstrate strong tenant demand?
- •Do you understand landlord responsibilities?
A qualified mortgage adviser helps evaluate numbers, borrowing capacity, and loan structuring to protect your primary residence where possible.
Equity is a Tool, Not a Guarantee
Using home equity for investment property purchases represents a potentially sound wealth-building strategy when executed thoughtfully. Successful investors combine financial literacy with strategic lending and strong market understanding.
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