Green Mortgage Loans: Lender Eligibility and Evidence

A green mortgage loan rewards an eligible energy-efficient home or funds approved improvements to an existing property. As at October 2026, Bank Australia has whole-home eligibility rules, while Westpac and ING have separate secured upgrade loans. The deciding evidence is the home’s rating and features, or the specific equipment being installed.

For your client’s purchase, start with the property certificate. For solar or other upgrades, start with the supplier’s quote and the existing mortgage. Compare the complete loan arrangement before treating a green benefit as a reason to change lenders.

What Lenders Count as Green

Lenders qualify either the home itself or the improvements financed, so a solar panel alone doesn’t establish eligibility for every green home mortgage. The Nationwide House Energy Rating Scheme (NatHERS) rates a home’s thermal performance on a ten-star scale. A lender can require both a minimum rating and additional features.

Under Bank Australia’s 14 May 2026 New Build criteria, homes need at least 7.5 stars and all-electric fixed appliances. Freestanding homes also need eligible rooftop solar. Apartments are exempt from the rooftop-solar requirement, but their common systems must also be all electric.

An upgrade loan uses an approved equipment or works list. As at October 2026, Westpac’s list covers selected energy-efficiency and climate-resilience work, while ING’s covers eligible energy-efficiency upgrades. The equipment specifications and installer rules determine whether the proposed work qualifies.

Finance structure	What qualifies	What it changes
Whole-home green feature	The property meets the lender’s rating and feature requirements	A benefit applies to the eligible home loan
Separate secured upgrade loan	Approved work on the property securing an eligible mortgage	Additional debt sits beside the main home loan
Personal loan for renovations or energy upgrades	The provider’s permitted purchase and credit requirements	A separate consumer loan funds the work, with its own security and term

A secured upgrade loan puts the home behind that additional borrowing. An unsecured personal loan doesn’t use the home as mortgage security. Compare repayment term and total cost as well as the green label.

Lenders With Green Home Loan Products

Bank Australia, Westpac and ING have different green lending routes available to brokers. The products below suit different projects, so they aren’t ranked by price.

Bank Australia Clean Energy Home Loan

Bank Australia’s Clean Energy Home Loan covers New Build and Renovate routes, as at October 2026. Its broker resources include eligibility documents for both. The benefit applies for five years on the variable option or the three-year fixed period.

The New Build route covers buying, building or refinancing a qualifying home. A completed property must have been built within the preceding 18 months. The eligible property value is capped at $2.5 million, alongside the green criteria described above.

Renovate is for an established, all-electric home with eligible upgrades completed during the 18 months before application. Bank Australia’s 14 May 2026 rules require two eligible upgrades where rooftop solar already exists, or three where rooftop solar is absent. Solar installation alone doesn’t satisfy this renovation route.

Westpac Sustainable Upgrades Home Loan

Westpac’s Sustainable Upgrades home loan is broker-submittable, as at October 2026. The additional loan is secured against the property being upgraded. Your client must have, or be approved for, a Westpac home or investment loan of at least $150,000.

The upgrade loan is $4,000 to $50,000, with principal-and-interest repayments over a maximum ten-year term. Only one is available per property, and lenders mortgage insurance (LMI) must not apply. LMI protects the lender when a borrower defaults.

Eligible energy upgrades include solar panels, batteries, electric vehicle charging and hot-water heat pumps through Westpac’s Origin quote route. Climate-resilience work includes specified bushfire-resistant materials and storm or flood measures. Westpac’s eligible upgrades page sets the work and installation requirements.

Westpac’s pricing includes support from the Clean Energy Finance Corporation (CEFC) through the Household Energy Upgrades Fund. The upgrade account has no establishment or monthly account fee. It has unlimited extra repayments, but no redraw, offset or package.

ING Green Upgrade Loan

ING’s Green Upgrade Loan broker page gives brokers an application route, as at October 2026. It adds a separate loan split to an eligible existing ING mortgage. Borrowing runs from $5,000 to $50,000 with a five-year fixed period.

ING’s customer eligibility requires at least $150,000 of existing mortgage balance and a security property worth no more than $2.5 million. The combined loan-to-value ratio (LVR), meaning debt divided by property value, must be 80% or less after settlement. An active Orange Everyday account must match the home loan’s name.

ING’s eligible list includes solar, batteries, heat pumps, induction cooktops, specified air conditioners, insulation, double glazing and other approved upgrades. Your client can use Home Energy Helper or an eligible installer of their choice. At the fixed period’s end, remaining debt converts to the variable Mortgage Simplifier loan.

The ING lender policy guide covers the broader mortgage assessment. If your client is changing lenders first, assess the refinance separately from the upgrade split.

St.George and ANZ Product Names

As at October 2026, St.George’s building and renovating page describes progressive construction funding, redraw and equity-funded top-ups. Those are standard funding routes. A request for a St.George green loan doesn’t establish entitlement to Westpac’s Sustainable Upgrades product, which requires a Westpac mortgage.

As at October 2026, ANZ’s Good Energy Home Loan is a New Zealand product. Keep that offer separate from an Australian application. Use the ANZ lender policy guide for Australian mortgage assessment rather than transferring overseas green-loan terms into the file.

Evidence Each Lender Requires

Collect evidence for the exact property and upgrade route before lodging, then track any installation documents needed to release funds. A quote can support an upgrade application, while completed work requires its final evidence.

Bank Australia

Bank Australia’s 14 May 2026 New Build rules require the NatHERS certificate, evidence of all-electric appliances and the occupancy or final-inspection document for a completed home. For freestanding homes, solar evidence must identify eligible equipment and the approved supplier and accredited installer. Accepted evidence includes a paid invoice, committed proposal, electrical safety certificate or signed building contract.

For construction, provide Bank Australia’s construction declaration with the mandatory-criteria evidence before the build is complete. The plans must support the proposed qualifying home. Keep the builder’s appliance and solar specifications consistent with those plans.

The Renovate rules, also effective 14 May 2026, require tax invoices or electrical safety compliance certificates for completed eligible upgrades. Documents need the installation address, date, equipment details and installer licence or accreditation information. The file must also show completion or payment in full.

Evidence of existing solar can include an invoice, electrical safety certificate or electricity bill under six months old showing generation or a feed-in tariff. If an eligible-upgrade invoice or safety certificate lacks required details, you can supplement it with a statement of supply or installation. Bank Australia accepts that statement only alongside a paid invoice or electrical safety compliance certificate.

Bank Australia’s eligibility evidence must predate application. Where eligibility can’t be verified, it can decline the application or remove the reduced rate and offer standard pricing. Don’t assume later renovations will qualify an already-lodged Renovate application.

Westpac

As at October 2026, Westpac requires the usual income, expense, asset and liability documents plus an eligible upgrade quote for unconditional approval. Energy-efficiency quotes follow its Origin route. Climate-resilience quotes must identify the work, supplier or installer, tradesperson’s licence number and installation address.

After approval and installation, provide the invoice so Westpac can pay the supplier or installer. For climate-resilience work, sign the tax invoice and include confirmation that the upgrade is installed. Missing final evidence leaves the payment request incomplete.

An installer deposit comes from your client’s funds initially. Westpac’s final-invoice process reimburses an approved deposit recorded on that invoice and pays the remaining supplier balance. Include that temporary cash requirement in the client’s budget.

ING

As at October 2026, ING’s application process uses the final quote for preliminary assessment and conditional approval. After installation, provide the final invoice for final approval and settlement. ING deposits funds into the client’s Orange Everyday account, and the client pays the installer.

A conditional approval doesn’t pay the installation bill. Agree the installer payment timing with your client before work begins, and provide the final invoice promptly after completion. Without it, ING can’t complete the published settlement process.

Compare the Benefit for the Client

Compare the green benefit against the client’s whole mortgage, required features and repayment plan. A concession on a small upgrade split can be outweighed by the cost of moving a much larger home loan. Include refinance costs, any fixed-loan break cost and the period after the green benefit ends.

Consider this fictional client. Priya has a $560,000 mortgage secured by a home valued at $800,000 and wants $20,000 of eligible solar and battery work. Her proposed combined borrowing is $580,000, so the LVR is 72.5%.

Under ING’s criteria as at October 2026, that arithmetic fits the 80% combined-LVR limit if the mortgage is already an eligible ING loan. Her property value and mortgage balance also fit the published limits. The matched account, eligible installation and credit assessment still matter.

If Priya already banks elsewhere, the green split requires a separate decision about refinancing her $560,000 mortgage. Under Westpac’s criteria as at October 2026, she would need an existing or approved qualifying Westpac mortgage. Westpac also requires LMI not to apply.

Decision	What Priya’s broker compares
Keep the main mortgage and fund upgrades separately	Total repayments and fees on the upgrade finance without changing the existing mortgage
Refinance and add a green split	Cost of the main mortgage and upgrade split together, including switching costs
Pay for part of the work from savings	Smaller borrowing against the emergency cash remaining after installation
Use a whole-home green feature	Whether the completed property meets every requirement and how long its benefit lasts

Priya wants an offset on her main mortgage and plans to repay the upgrade debt within five years. Keep those requirements in the comparison. A longer term lowers scheduled repayments but can increase interest paid over the life of the upgrade debt.

Bank Australia’s benefit, as at October 2026, ends after its stated variable or fixed benefit period. Its evidence rules can also remove the concession before approval. Westpac and ING require the installation invoice at the funding stage, so include that document in the settlement plan.

Your broker can use Bulma’s Policy Advisor to compare lender policy requirements and retain the quoted wording in the file. Obtain product pricing directly from the lender for the cost comparison. Select the route that funds the eligible work, preserves the required mortgage features and fits the client’s repayment budget.