Chattel Mortgage Explained and How It Works for Your Business
July 22, 2026
Renovations rarely go wrong at the building stage. They go wrong at the arithmetic stage, months earlier, when a budget is set against a quote rather than against reality. Financing the work is part of that arithmetic. A personal loan is one of several ways to fund a renovation, and it suits some situations well and others poorly. What follows is how the loan actually works, what a comparison rate is really telling you, what the contract rules require in Queensland, and where budgets tend to come apart.
TLDR
- A personal loan does not use your home as security, which is its main structural advantage over borrowing against the property.
- Personal loans may be secured or unsecured. Secured loans usually carry a lower rate and put an asset at risk.
- The comparison rate, not the advertised interest rate, is the figure to compare, because it folds in most fees.
- In Queensland, domestic building work priced over $3,300 requires a written contract, and that includes renovations, extensions and kitchen or bathroom refits.
- For work priced at $20,000 or more, the contractor must give you the QBCC consumer building guide before you sign.
- Build a contingency into the budget. Variations and prime cost items are where the surprises live.
- Compare a personal loan against a mortgage redraw or top-up before deciding. The cheaper rate is not always the cheaper loan.
When a personal loan fits
A personal loan is a fixed sum, repaid over a set term, usually between one and seven years. For a renovation, that structure has a particular appeal. The debt has an end date, and the repayments do not stretch across the remaining life of a mortgage.
It also does not touch your home. Borrowing against the property, through a redraw or a top-up, means the renovation debt sits behind the same security as the mortgage. A personal loan does not, and for some households that separation is worth paying for.
The structure tends to suit mid-sized projects: a bathroom, a kitchen, a deck, solar, a re-roof. Very large structural works often call for a different facility altogether. Local considerations matter too, and renovation lending in Brisbane and surrounding areas involves the same lending principles applied to quite different property values and trade availability.
Secured and unsecured explained
Moneysmart notes that a personal loan may be secured or unsecured, depending on whether you offer an asset as security. The distinction is not cosmetic.
A secured loan is backed by an asset, commonly a vehicle. The lender takes on less risk, so the interest rate is usually lower. If you cannot repay, the lender can take the asset. An unsecured loan has no such backing, which typically means a higher rate and no asset at risk beyond the ordinary consequences of default.
Most renovation borrowing is done through unsecured personal loans, because the thing being improved is the home, and putting the home up as security turns the arrangement into something closer to a mortgage. Whether that trade is worth making depends on the rate difference and on how comfortable you are with the security.
Reading the comparison rate
Advertised interest rates are designed to be attractive. The comparison rate exists because they are also incomplete.
A comparison rate folds most fees and charges into a single percentage, so that two loans can be measured against each other on something closer to like-for-like terms. Moneysmart’s guidance makes the point neatly: a loan can advertise a low interest rate and still carry a higher comparison rate, because it charges higher fees.
Two habits follow. Compare comparison rates rather than headline rates. And read what the comparison rate does not include, which typically covers fees that depend on your behaviour, such as early repayment or late payment charges.
How much to actually borrow
The instinct is to borrow the quoted amount. The quote is not the project cost. It is the cost of the work as scoped, on the information available, before anything is opened up.
Two contract mechanisms explain most of the gap. Prime cost items are allowances for goods whose actual price is not yet known, such as tapware or tiles. Provisional sums are allowances for work whose extent is not yet known. Both are estimates written into the contract, and both are adjusted when the real figure arrives. QBCC contracts contain dedicated schedules for each, which tells you how routine this is.
Then there are variations, which are changes to the scope agreed after signing. Some are elective. Many are not, particularly in older homes where what is behind a wall is a matter of speculation until the wall comes down.
Borrowing slightly more than the quote, or holding a separate cash contingency, is not pessimism. It is how you avoid stopping work halfway through to arrange more finance, which is both expensive and slow.
What Queensland contract rules require
If you are renovating in Queensland, the Queensland Building and Construction Commission sets rules that exist to protect you, and knowing them changes what you should expect from a builder.
Contract price | What is required | Key obligations |
Up to $3,300 | A small building projects contract may be used | It is illegal to use this contract for work priced over $3,300 |
Over $3,300 | A written contract is required, including labour, materials and GST | A contractor commits an offence if they do not use a compliant written contract |
$3,301 to $19,999 | Level 1 renovation, extension and repair contract | Signed and dated contract given to you within 5 business days |
$20,000 and over | Level 2 renovation, extension and repair contract | Consumer building guide before you sign, contract within 5 business days, commencement notice within 10 business days |
The QBCC defines domestic building work broadly. It includes renovating, extending, altering, improving or repairing a house, duplex or unit, refitting a kitchen or bathroom, and landscaping, paving and site work. Most renovation projects fall inside it comfortably.
If a contractor proposes to skip the written contract on a job priced over $3,300, that is not a shortcut and it is not a favour. Other states and territories have their own regulators and thresholds, so check the equivalent body if you are renovating outside Queensland.
Where renovation budgets go wrong
The finance is rarely the problem in isolation. The problem is a budget that had no slack in it meeting a project that needed some.
- Borrowing exactly the quoted amount, leaving nothing for prime cost adjustments or variations
- Comparing headline interest rates instead of comparison rates
- Choosing a longer term to reduce repayments without calculating the additional interest paid
- Forgetting that some renovations trigger council approvals, certification or utility connection costs
- Beginning work before finance is settled, then borrowing under time pressure
- Making several credit applications in a short period, each of which is recorded on your credit report
- Reaching for high-cost short-term credit when a shortfall appears mid-project
That last point deserves emphasis. A mid-project shortfall creates urgency, and urgency is expensive. Thinking through managing sudden costs before the shortfall arrives is considerably cheaper than solving it afterwards.
Alternatives worth comparing
A personal loan is one option among several, and the lowest advertised rate does not automatically produce the lowest total cost.
Option | How it works | Worth knowing |
Unsecured personal loan | Fixed sum over a set term, no security over the home | Higher rate than mortgage borrowing, but the debt has a defined end date |
Mortgage redraw | Draw on extra repayments already made | Rate is low, but the amount is spread over the remaining mortgage term unless you repay it faster |
Home loan top-up | Increase the mortgage against the property | Lowest rate, longest term. Interest paid over 25 years can exceed a higher-rate short loan |
Construction or renovation loan | Funds released in stages against progress | Suited to larger structural work, more administration |
Credit card or buy now pay later | Revolving or short-term credit | Generally the most expensive way to fund building work |
The right comparison is total interest paid over the life of the debt, alongside how the borrowing sits against your home. Looking across a range of loan options with those two questions in hand tends to be more productive than sorting by advertised rate.
What lenders will ask for
Lenders assess capacity to repay, not enthusiasm for the project. Expect questions about income, existing debts and living expenses, and expect them to look at your credit report.
Preparing before you apply is straightforward. Have recent payslips or, if self-employed, tax returns and financial statements. Know your existing commitments. Read your own credit report first, since you can access it free every three months, and correct anything that is wrong before a lender sees it.
Have the quote itself, and be able to explain the scope. A clear, costed project reads differently to an estimate scribbled on the back of an inspection report.
Ready to plan your renovation?
A personal loan can be a sensible way to fund a renovation. It keeps the debt separate from the home, it has an end date, and the discipline of a fixed term suits a project with a defined scope. It is usually a higher rate than borrowing against the property, and it is worth doing that comparison honestly rather than by instinct.
Whichever way you fund it, size the budget for the project you will actually have rather than the one on the quote, insist on the written contract the law requires, and understand the comparison rate before you sign.
If you are unsure which structure suits your circumstances, a broker can explain how different lenders assess an application and what each will want to see. Eligibility, rates and terms vary between lenders and depend on your individual circumstances.
Sources: ASIC Moneysmart, Personal loans, and the Moneysmart credit factsheet on personal loans; ASIC Moneysmart, Credit scores and credit reports; Queensland Building and Construction Commission, Domestic building contracts (last reviewed 26 June 2024), including contract levels, thresholds and the consumer building guide obligation; Queensland Building and Construction Commission Act, Schedule 1B.
This article is intended for general information purposes only. It does not take into account your objectives, financial situation or needs, and it does not constitute financial, credit or legal advice. Building contract requirements described here apply in Queensland and are current as at the QBCC guidance cited. Other states and territories have different regulators and thresholds. Eligibility, interest rates, fees and terms vary between lenders and depend on your individual circumstances, and no outcome is guaranteed. Consider seeking independent advice before making a financial decision, and refer to moneysmart.gov.au for free, impartial guidance. Thor Finance is a Credit Representative (ACR 557246) of AFAS Group Pty Ltd (Australian Credit Licence 414426).
