The builder you choose determines the outcome of your renovation more than the design, the materials or the budget. A good builder on a modest budget produces a house you enjoy for twenty years. A bad builder with an unlimited budget produces litigation. Adelaide’s building industry is small enough that reputations are known and large enough that plenty of operators are unknown to you, and the vetting process is where most homeowners under-invest.
A related guide to consider while planning this work is Renovating on Reactive Clay Soil: What to Discuss with Your Engineer.
This guide covers how builder licensing works in South Australia, what to check, how to compare quotes meaningfully, and the warning signs worth walking away from.
Licensing in South Australia
Residential building work in South Australia is regulated by Consumer and Business Services, which issues building work contractor licences. Anyone contracting to carry out building work above the prescribed value must hold one.
What to verify
- The licence number and that it is current. CBS maintains a public register you can search by name or licence number. Do this yourself rather than accepting a number printed on a quote.
- That the licence is in the correct category for the work — a building work contractor licence covers general building work; specialist trades hold their own.
- That the licensed entity is the one you are contracting with. A common problem is a licence held by one company and the contract offered by a related entity that has no licence and no assets.
- Whether there are conditions on the licence, which the register will show.
- Disciplinary history. Search the builder’s name and the company name, and check whether any related entity has been through liquidation.
Building Indemnity Insurance
This is the strongest consumer protection in the South Australian system and the single best test of a builder’s standing.
- Required for domestic building work requiring building consent above $20,000 — the threshold rose from $12,000 in November 2025
- The certificate must be provided to you and the council before building work commences
- Cover with current insurers is up to $250,000, raised from $150,000 in late 2025
- Claims for defective work can generally be made up to five years after the work is completed
- It responds where the builder dies, disappears or becomes insolvent — it is not a general warranty for workmanship you are unhappy with
The important point is what it tells you. Insurers assess a builder’s financial position and history before issuing cover, and they set limits on how much work each builder can have insured at once. A builder who cannot obtain the insurance, or who wants to structure the job to stay under the threshold, has failed a test conducted by people with money at stake. Ask for the certificate before you pay any deposit, and verify it with the insurer if the amount is significant.
Finding Candidates
Sources that produce good builders
- Houses you have actually seen. Knock on the door of a renovation you admire in your suburb and ask who did it. Adelaide is a city where this works.
- Your designer or architect. They know who prices honestly, who reads drawings, and who they would not work with again. Ask specifically who they would not recommend and why.
- Trade referrals. Electricians, plumbers and cabinetmakers know exactly which builders pay on time and run organised sites.
- Industry associations. Master Builders SA and HIA membership is not a guarantee, but it indicates an established business with something to lose.
- Specialists in your housing type. A builder who has renovated twenty bluestone villas is worth substantially more than a generalist on that stock. The same applies to Hills bushfire-zone work and coastal construction.
Sources to treat with caution
- Lead-generation websites that sell your enquiry to whoever pays for it
- Unsolicited door-knocking, particularly after storms
- Social media advertising with impressive photography and no verifiable project history
- Anyone whose first move is a discount for signing this week
The Vetting Process
Before you send drawings
- Verify the CBS licence on the public register
- Search ASIC for the company, its directors, and any related entities — repeated company failures under the same directors are the clearest warning available
- Ask how long the business has traded under this name and this entity
- Ask how many jobs they run concurrently and who supervises each
- Ask whether the job would be run by the person you are speaking to
References that actually tell you something
Ask for three references: a job completed in the last twelve months, one completed two to three years ago, and one that went wrong. The refusal to nominate the third is itself informative — every builder has had a difficult job, and the honest ones will tell you about it.
When you call a reference, do not ask whether they were happy. Ask:
- How did the final cost compare with the contract sum, and what caused the difference?
- How many variations were there, and were they priced before or after the work was done?
- How did the actual program compare with the contracted one?
- How did the builder handle the first thing that went wrong?
- How long did defects take to be rectified after handover?
- Were subcontractors paid on time? Did anyone come to you about unpaid accounts?
- Would you use them again, and is there anything you would do differently?
Visit a site
Ask to walk through a job currently under construction. Look at:
- Whether the site is tidy, materials are stored properly and waste is contained
- Whether there is a site toilet, safety fencing and clear signage
- Whether the trades on site know what they are doing next week
- The quality of the framing, the plumbing rough-in and the waterproofing detail — the parts that get covered up
- Whether the neighbours look aggrieved
Comparing Quotes
Adelaide renovation quotes routinely spread 30 to 50 per cent across three builders on the same drawings. That spread is almost never about greed. It is about scope, allowances and exclusions.
A related guide to consider while planning this work is How Much Does a Home Renovation Cost in Adelaide? A 2026 Price Guide.
Equalise before you compare
- Provisional sums and prime cost items. A quote with a $12,000 PC allowance for a kitchen and one with $30,000 are not comparable. List every allowance side by side.
- Exclusions. Read them carefully. Asbestos removal, salt damp remediation, footing upgrades on discovery, tree removal, and service upgrades are all common exclusions that become variations.
- Preliminaries. Site establishment, scaffolding, temporary fencing, site toilet, waste removal, insurances, supervision. A quote that omits these is not cheaper.
- Footings. Ask whether the price is based on the engineer’s design for the actual site classification, or on an assumption. On Adelaide’s reactive clay this is the largest single risk item.
- Margin. A builder’s margin of 15 to 25 per cent on a renovation is normal. Anyone at 5 per cent has either mispriced the job or intends to make it up in variations.
- Rise and fall. Is the price fixed, or subject to material cost movement?
- Program. How many weeks, and are liquidated damages specified for late completion?
Once you have equalised the scope, the quotes usually converge within about 15 per cent, and at that point you are choosing on the builder rather than the price. If one quote is still dramatically lower, ask why. Frequently the answer is that they have not allowed for something you will pay for later.
The Contract
Use a standard-form domestic building contract — Master Builders SA or HIA — rather than a builder’s own document or a letter of engagement. The standard forms are balanced and courts understand them.
What to check before signing
- The contract price and what it includes, with the full scope, drawings and specification attached and initialled
- The progress payment schedule. Payments should follow completed stages, and each stage should be worth roughly what has been done. Never pay ahead of the work.
- The deposit. Regulated as a maximum percentage of the contract price. A builder asking for 20 or 30 per cent up front is a serious warning sign.
- The variation process. Variations must be documented and priced in writing before the work is carried out. This single clause prevents most disputes.
- The program, the start date, and the grounds for extension of time
- The defects liability period and the process for rectification
- The Building Indemnity Insurance certificate, attached, before any money changes hands
- Dispute resolution provisions
Have a solicitor who does building work review the contract. It costs a few hundred dollars against a contract of several hundred thousand.
Red Flags
- Reluctance to provide the Building Indemnity Insurance certificate, or a suggestion to keep the job under $20,000 to avoid it
- A large deposit beyond the regulated maximum
- Cash discounts — no receipt, no contract, no protection, no recourse
- No written contract for work of significance
- Pressure to sign quickly or a price that expires
- A quote on a single page with no scope, no exclusions and no specification
- Refusal to provide references or site access
- A licence held by a different entity from the one on the contract
- Directors with a history of failed building companies
- Vagueness about who supervises the site day to day
- Disparaging every other builder you mention
- Verbal assurances about things that are excluded in writing
Managing the Relationship
Once you have chosen well, most of your job is staying organised.
- Put everything in writing. Confirm site conversations by email the same day. “Just confirming we agreed the pantry door swings the other way” takes thirty seconds and prevents an argument in eight weeks.
- Make decisions before construction starts. Every selection locked and documented. Decisions made on site are made at build-time prices with no competitive tension.
- Approve variations in writing before the work happens. Never after.
- Visit regularly but do not direct the trades. Concerns go to the builder, not to the tiler.
- Photograph everything before it is covered. Framing, services rough-in, waterproofing, insulation. Date-stamped, from multiple angles. This documentation is worth more than any contract clause if something fails later.
- Pay on time when the stage is complete. A builder carrying you is a builder prioritising someone else’s job.
- Keep a running file of the contract, drawings, variations, certificates, compliance documents and correspondence.
Handover
Before the final payment, collect:
- The Certificate of Occupancy or the relevant completion documentation
- Electrical Certificate of Compliance
- Plumbing compliance certification
- Waterproofing certification and the photographic record
- Termite management documentation where applicable
- Glazing and smoke alarm compliance
- Engineer’s inspection records for the footings and structural work
- Warranties and manuals for every appliance, fixture and system
- The Building Indemnity Insurance certificate for your records
- A signed defects list with agreed rectification dates
Withhold the final payment until the defects list is complete. It is the only leverage you have left, and once it is paid, rectification moves to the bottom of everyone’s priority list.
Choosing a builder well is the highest-return hour of work in the entire project. For the budget framework that sits around this decision, see the Adelaide renovation cost guide, and for what goes wrong when the vetting is skipped, the most expensive renovation mistakes people make in Adelaide.
When Things Go Wrong: Your Options in South Australia
Most renovations finish without a formal dispute. When one does arise, knowing the sequence of options prevents a recoverable problem from becoming an unrecoverable one.
Step one: raise it properly, in writing
- Describe the specific defect or issue, with reference to the contract, the drawings or the relevant standard
- Include dated photographs
- Propose what you want done and by when
- Keep it factual and unemotional — this document may be read by a third party later
- Send it by email so there is a record of delivery
A surprising proportion of disputes resolve at this stage simply because the issue had not been clearly stated.
Step two: use the contract’s dispute process
Standard-form domestic building contracts contain a dispute resolution clause setting out notice requirements and steps. Follow it precisely — failing to follow the contractual process can weaken your position later.
Step three: independent expert assessment
Engage an independent building consultant to inspect and report against the relevant standards. A written expert report costing $800 to $2,500 changes the nature of the conversation considerably, and it is the document any subsequent process will rely on.
Step four: Consumer and Business Services
CBS regulates building work contractors in South Australia and can take disciplinary action against licensees. Lodging a complaint creates a record and may prompt resolution, though CBS is a regulator rather than a body that awards compensation to individuals.
Step five: tribunal or court
Building disputes can be pursued through the relevant South Australian tribunal or court depending on the amount in issue. Get legal advice from a solicitor who does building work before commencing — the costs and timeframes are significant, and the availability of each forum depends on the claim.
Where Building Indemnity Insurance fits
The insurance responds where the builder has died, disappeared or become insolvent, for incomplete work and for defective work, with claims for defective work generally available up to five years after completion and cover currently up to $250,000. It is not a general remedy for workmanship you are dissatisfied with while the builder is still trading and contactable — in that situation the contract and the dispute process are your route.
The Questions to Ask at the First Meeting
The initial conversation with a prospective builder tells you more than any reference will, provided you ask the right things and listen to how they are answered rather than just what is said.
- How many jobs do you run at once, and who supervises each one? Listen for whether the person in front of you will be on your site or whether you are being sold by one person and delivered by another.
- Have you worked on this type of house before? A builder who has renovated twenty bluestone villas knows things about salt damp, lime mortar and structural openings in stone that a generalist does not.
- What do you think will be the hard part of this job? A builder who identifies the footings, the salt damp or the junction between old and new is thinking about the actual project. One who says it is all straightforward has not looked.
- What would you change about this design to make it build better or cost less? Good builders always have an answer, and it is usually worth money.
- How do you handle variations? The answer should be that they are priced and approved in writing before the work is done. Any other answer is a warning.
- What is your current lead time? Anyone available next week in a busy market is worth understanding better.
- Who are your regular subcontractors and how long have you used them? Stable trade relationships are the strongest predictor of a well-run site.
- What went wrong on your last job and how did you deal with it? Every builder has an answer. The ones who give it candidly are the ones who will tell you the truth when it happens on yours.