Financing a granny flat in Frankston.
Three main funding paths, a realistic look at Frankston rental yields, and the numbers on how long it takes to get your money back. This is general information — not financial advice. Talk to your broker and accountant before committing to a structure.
Equity redraw & equity release.
How it works.
If you’ve held your Frankston property for more than five years, there’s a reasonable chance your home has grown enough in value that you have significant equity sitting in it. Most lenders will allow you to draw that equity via a redraw facility on your existing mortgage or a new split loan, up to a combined loan-to-value ratio (LVR) of 80% without requiring lenders mortgage insurance.
Example: Frankston home valued at $750,000, existing mortgage $350,000. Usable equity at 80% LVR: $250,000 ($750,000 × 0.80 − $350,000). A standard 1-bedroom granny flat including all permits runs $155,000–$200,000. That equity comfortably covers it without a second loan product.
Advantages for Frankston homeowners.
- Simplest structure — one lender, one loan, existing relationship.
- No separate construction loan origination fees or second valuation.
- You control disbursement timing against the builder’s progress payment schedule.
- Interest on borrowed funds used for income-producing purposes is generally deductible — confirm with your accountant.
Things to check.
- Your lender will re-value the property before increasing the facility — current Frankston market conditions affect what equity is available.
- Some lenders require a ‘second dwelling permit’ or approval before releasing funds for a granny flat — check this early.
- Drawing equity increases your repayments on the main loan — model the cash flow impact before proceeding.
General information only — not financial advice. Speak to a licensed mortgage broker or financial adviser.
Construction loan with progress draws.
Designed for building, not buying.
A construction loan releases funds in stages aligned with your builder’s progress payment schedule. For a typical Frankston granny flat, the payment schedule looks something like this:
- Deposit (5–10%): On signing the building contract — covers initial design, permit lodgement and material orders.
- Base / slab (15–20%): On slab completion and RBS inspection sign-off.
- Frame (20–25%): On frame completion and RBS frame inspection.
- Lock-up (25%): On external cladding, windows and doors installed — building is weather-tight.
- Practical completion (10–15%): On occupancy permit issued and keys handed over.
- Retention (2.5–5%): Held for 3–6 months, released after defect rectification period.
During construction — interest only.
Construction loans are typically interest-only during the build period, charged on the drawn balance. If you’ve drawn $80,000 of a $180,000 facility at stage 3, you’re only paying interest on $80,000 — not $180,000. Once the occupancy permit issues, the loan converts to principal & interest. Frankston granny flat construction loans typically run 12–18 months before conversion.
See the full cost breakdown to understand all line items your loan needs to cover, including council and building permits.
General information only — not financial advice. Confirm structure with a licensed mortgage broker.
Specialist secondary-dwelling loans.
Loans designed around income-producing second dwellings.
A small number of Australian lenders have developed specific loan products for secondary dwellings. The key difference is that these lenders may factor the projected rental income of the granny flat into your borrowing capacity, rather than assessing you purely on existing income. For Frankston borrowers with modest equity but strong rental projections, this can meaningfully increase what is available.
What lenders typically require.
- A rental appraisal letter from a local property manager (Frankston and Peninsula PMs can provide this).
- A planning permit or permit-free confirmation for the proposed dwelling.
- Evidence the second dwelling will be a legally compliant, separately tenantable residence (not a DPU).
- In some cases, the main dwelling must be at a lower LVR (<60%) to qualify.
A mortgage broker who specialises in investment property and secondary dwellings is the most efficient way to access these products. We can refer you to brokers active in the Frankston and Mornington Peninsula market.
General information only — not financial advice. Obtain independent advice before acting.
Frankston & Peninsula rental yields and payback.
Current rental market — 2026.
Based on Frankston and inner-Peninsula rental listings in early 2026:
- 1-bedroom granny flat, Frankston / Seaford / Carrum Downs: $320–$380 per week.
- 2-bedroom granny flat, Frankston / Carrum Downs: $400–$460 per week.
- 1-bedroom, Frankston South / Mt Eliza / Mornington: $350–$420 per week (10–15% premium).
- NDIS SDA (Improved Liveability), any Frankston City location: $420–$540 per week.
See our rental income page for a more detailed breakdown of gross vs net yield accounting for vacancy, management fees and maintenance.
Worked payback example — 1-bedroom in Frankston.
- All-in build cost (including permits and connections): $170,000
- Weekly rent: $350
- Annual gross rent: $18,200
- Gross yield: 10.7%
- Net yield (after 8% vacancy, 8% management, $2,000 maintenance): ~8.9%
- Net annual cash: ~$15,100
- Simple payback: approximately 11.3 years
Capital appreciation during that period is excluded from this calculation but is a meaningful component of total return for Frankston and Peninsula properties. The granny flat typically adds 60–80% of its build cost to the property’s assessed value at completion.
Depreciation and tax notes.
New residential construction qualifies for Division 43 (building allowance) at 2.5% per year and Division 40 (plant & equipment) depreciation on fixtures. A quantity surveyor’s tax depreciation schedule, typically $600–$900 for a granny flat, can materially improve cash flow in the early years. This is general information only — always confirm your specific position with a registered tax agent or accountant.
Does a granny flat add to my property value?
A compliant, well-built second dwelling typically adds value to a Frankston or Peninsula property — but the uplift rarely equals the build cost on the day of completion. In a market where similar homes with granny flats attract a buyer premium, the uplift compounds over time alongside the rental income.
Key factors that influence the uplift on a Frankston property:
- Liveability of the second dwelling: Well-designed with separate entry, outdoor space and parking will achieve a stronger result than a cramped, dark unit.
- Lot size: Large Frankston South or Mt Eliza blocks where the granny flat doesn’t compromise the main home’s yard typically see stronger uplift.
- Occupancy permit status: An unapproved or DPU-restricted dwelling does not add the same value as a fully permitted second dwelling. Lenders will also not lend against unapproved structures.
- Proximity to amenities: Frankston CBD, train stations and Frankston Hospital catchments drive stronger rental demand and buyer appetite.
For a formal view of the likely uplift on your specific property, a registered property valuer is the only reliable source. We are builders, not valuers — and we will not quote you a speculative value uplift to help close a sale.
This page is general information only and does not constitute financial or investment advice. Seek independent advice from a licensed adviser before making financial decisions.
Frequently asked questions.
Can I use equity in my Frankston home to fund a granny flat?
Yes. Equity redraw or an equity release facility against your existing Frankston property is the most common funding path. If your home has grown in value since purchase, you may already have the equity to cover a full 1-bedroom build without a new loan. Your bank or mortgage broker can advise on current loan-to-value thresholds. This is general information — speak to your broker before acting.
What is a construction loan and how does it work for a granny flat?
A construction loan releases funds in stages — typically 5 draws matching your builder’s progress payment schedule (deposit, slab, frame, lock-up, practical completion). You only pay interest on the amount drawn, not the full loan, during construction. Once the occupancy permit issues, the loan usually converts to a standard mortgage. Frankston granny flat construction loans typically run 12–18 months before conversion.
What rental yield can I expect from a Frankston granny flat in 2026?
Frankston 1-bedroom granny flats achieve $320–$380 per week in 2026 market conditions. 2-bedroom flats fetch $400–$460 per week. Frankston South and Mt Eliza command a 10–15% premium. Mornington Peninsula rents average slightly higher on the Peninsula towns but with more seasonal variability. At $340/wk net rent, a $165,000 1-bedroom build returns roughly 10.7% gross yield before costs.
Does a granny flat add value to my Frankston property?
Generally yes, though the added value rarely equals the build cost dollar-for-dollar at the time of completion. Most Frankston properties with a compliant, well-designed second dwelling show a valuation uplift of 60–80% of the build cost at completion, with the balance recovered over time through rental income and ongoing capital growth. Location, block size and dwelling quality all affect the result. Obtain a formal valuation from a registered valuer for your specific property.
Are there specialist granny flat loan products available in Australia?
Yes. Several Australian lenders offer secondary-dwelling or ‘granny flat’ loan products that treat the second dwelling as an income-producing asset, which can improve your borrowing capacity compared to a standard construction loan. Eligibility criteria vary — some require a rental appraisal letter, others require the land to already be mortgage-free or at low LVR. A mortgage broker who specialises in investment lending is the best starting point for Frankston and Peninsula borrowers.
Where we build.
Numbers first. Fixed-price quote next.
Site feasibility, honest cost breakdown and a written quote you can take to your broker.