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How to Use the Equity in Your Own Home to Buy an Investment Property

12 March 20258 min readBy Jarrod Kirkland
How to Use the Equity in Your Own Home to Buy an Investment Property

Key Takeaways

  • 1Most investors fund deposits using existing home equity rather than cash savings.
  • 2Cross-collateralisation offers convenience but carries risk-problems with one property could affect both.
  • 3Investment property mortgage interest may be tax-deductible subject to current legislation.
  • 4Consult a mortgage adviser to evaluate structuring that protects your primary residence.

If you already own your home, you might be sitting on a hidden asset that could help you grow your wealth: equity.

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

1No Cash Deposit Required - Home appreciation can eliminate the need for substantial savings accumulation.
2Accelerated Portfolio Growth - Leveraging equity enables faster property investment goals.
3Tax-Deductible Interest - Investment property mortgage interest may be tax-deductible (subject to current legislation).

Risks and Considerations

1Increased Debt Burden - Using equity means greater lending exposure.
2Property Market Fluctuations - Declining house prices reduce equity and may increase your LVR.
3Interest Rate Changes - Even currently cashflowing properties face pressure from rate increases.

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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Frequently Asked Questions

How do I calculate my usable equity?

Banks typically permit borrowing up to 80% of your home value under standard [LVR rules](/blog/what-does-lvr-mean). Usable equity equals (home value x 80%) minus your current mortgage balance. For example, a $900,000 home with $500,000 owing has usable equity of $220,000, which could serve as your investment property deposit without requiring additional cash savings.

How much deposit do I need for an investment property?

Investment properties typically require a 30% deposit for existing properties, though [new builds may allow as little as 10-20%](/blog/new-build-vs-existing-home-which-is-right-for-you) due to LVR exemptions. For a $700,000 investment property, you would need $210,000 for an existing property or potentially $70,000-$140,000 for a new build. Your home equity can serve as this deposit.

What are the two ways to access equity for investment?

The first option is a [mortgage top-up](/blog/can-i-get-a-top-up-on-my-mortgage), where you increase your existing mortgage to release equity for the new deposit. The second option is cross-collateralisation, where both properties secure a single lending arrangement. Cross-collateralisation offers convenience but carries risk - problems with one property could affect both, so discuss structuring options with your mortgage adviser.

What will the bank assess beyond my equity?

Beyond equity availability, banks assess your ability to service both mortgages including your income, expenses, existing debts, and the expected rental income from the new property. Rental income is typically scaled at 65-80% to account for vacancies and expenses. Your [debt-to-income ratio](/blog/debt-to-income-ratios-what-are-they-and-how-are-they-measured) must also meet lender requirements.

What are the main benefits of using equity to invest?

Using equity means no cash deposit is required - your home appreciation can eliminate the need for substantial savings accumulation. It enables accelerated portfolio growth compared to saving each deposit from scratch. Additionally, investment property mortgage interest may be tax-deductible for new builds, subject to current legislation. Learn more about [preparing to buy an investment property](/blog/3-things-investment-property-buyers-can-today-get-ready-buy).

What are the risks of using equity to invest in property?

Key risks include increased debt burden and exposure to property market fluctuations - declining house prices can reduce your equity and increase your LVR. Interest rate changes can affect cashflow even on currently positive properties. Ensure you can afford payments if rental income drops or rates rise, and consider whether your primary residence could be at risk if cross-collateralised.

Should I separate my home loan from my investment loan?

Separating your loans provides greater protection for your primary residence and more flexibility for future decisions. If one property needs to be sold or encounters issues, the other remains unaffected. A qualified mortgage adviser can help structure your lending to protect your family home while still enabling investment growth.

How do I know if Im ready to use equity to invest?

Consider whether you can afford payments if rental income drops or rates rise significantly, whether the investment area has strong tenant demand, and whether you understand [landlord responsibilities](/blog/the-top-fears-landlords-have-about-tenants-and-how-to-manage-them). Calculate your potential rental yield and ensure you have emergency funds beyond your equity. Speaking with a mortgage adviser helps evaluate whether you are truly ready.

Disclaimer

The information on this website is for general guidance only and does not constitute financial or investment advice. Always do your own research and seek personalised advice from a qualified financial adviser or mortgage adviser before making financial decisions. All investments carry risk and past performance is not indicative of future results.

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