Whether you are planning a renovation in Subiaco, building a new home in Baldivis, or adding an extension in Joondalup, the builder you choose will define your entire project experience. Hiring a licensed builder in Western Australia is the most effective way to protect your investment and your property. With over 12,400 registered builders in WA, the state has one of the largest builder workforces in Australia. But not every registered builder is the right fit for your project, and an unregistered one could leave you with no legal protection at all. This guide covers everything you need to know to find and hire a licensed builder in Western Australia. From DEMIRS registration checks and home indemnity insurance to the Home Building Contracts Act, deposit limits, and dispute resolution, it is all here. Start by browsing licensed builders in TradieVerify’s WA builder directory.
Why You Need a Registered Builder in Western Australia
The Building Services (Registration) Act 2011 governs builder registration in Western Australia. If your project involves building work valued at $20,000 or more (including labour and materials), the person performing that work must be a registered building contractor with the Building Services Board. This is a legal requirement enforced by DEMIRS (Department of Mines, Industry Regulation and Safety).
Legal protection. A registered builder in WA has met qualification and experience requirements, holds appropriate insurance, and operates under regulatory oversight. Their work must comply with the National Construction Code and WA building regulations.
Home indemnity insurance. When you hire a licensed builder in Western Australia for residential work over $20,000, they must take out home indemnity insurance in your name before accepting any payment or starting work. This protects you if the builder dies, disappears, or becomes insolvent before completing the job or fixing defects.
Accountability. Registered builders are listed on the DEMIRS register. If a dispute arises, the Building Commissioner can investigate, issue building remediation orders, and refer matters to the State Administrative Tribunal (SAT). With an unregistered operator, you have almost no regulatory recourse.
Penalties. Builders who fail to take out home indemnity insurance face fines of up to $50,000 and risk losing their registration. Performing building work without registration is also an offence under WA law.
You can check any WA builder’s registration status on TradieVerify’s search page in seconds.
How to Check a Builder’s Registration in WA
Before you sign a contract or pay any money, verify the builder’s registration with DEMIRS. This takes a few minutes and can save you tens of thousands of dollars.
Step 1: Use TradieVerify search. Head to TradieVerify’s licence search and enter the builder’s name or registration number. TradieVerify cross-references DEMIRS data so you can confirm their registration status and type in one place. This is the fastest way to hire a licensed builder in Western Australia with confidence.
Step 2: Verify on the DEMIRS Online Licence Search. For a second check, visit the DEMIRS Online Licence Search at ols.demirs.wa.gov.au. Search by name or registration number and confirm the details match what the builder provided.
What to check on the registration:
- Registration number — does it match the number on their quote, contract, and advertising? Building contractors have a “BC” prefix, building practitioners have “BP”.
- Registration type — is it a building contractor registration (required to contract for work) or a building practitioner registration only?
- Expiry date — is the registration current? Registrations must be renewed every three years.
- Conditions — are there any restrictions or limitations on the registration?
Red flag: contractor vs practitioner. A building practitioner (BP) registration allows someone to supervise building work and be named on a building permit. However, only a registered building contractor (BC) can enter into a contract with you to carry out building work. If someone with only a BP registration offers to contract for your project, they are operating outside their registration scope.
You can also browse licensed builders in WA on TradieVerify to find registered builders in your area.
Understanding WA Builder Registration Types
Not all builder registrations are the same. Before you hire a builder in Western Australia, make sure their registration type and building classes match your project.
Registration Types
| Registration Type | What It Allows |
|---|---|
| Building Contractor (BC) | Can contract directly with homeowners to carry out building work. Can operate a building business. Must meet financial and business competency requirements. |
| Building Practitioner (BP) | Can be named on a building permit as the builder. Can supervise building work. Cannot contract directly with clients for building work. |
Building Classes
Builder registrations in WA are linked to National Construction Code (NCC) building classifications. The most relevant for homeowners are:
| NCC Class | Building Type |
|---|---|
| Class 1a | Single detached house, terrace house, townhouse, villa |
| Class 1b | Small boarding house, guest house (up to 12 people) |
| Class 10a | Non-habitable building: garage, carport, shed |
| Class 10b | Non-habitable structure: fence, retaining wall, swimming pool |
A builder registered for Class 1 and 10 work can handle the full range of domestic building projects. Some builders may be registered for specific classes only, so always check that their registration covers your project type.
Nominated supervisor. Every registered building contractor must have a nominated registered building practitioner who is responsible for supervising the building work. Ask your builder who their nominated supervisor is and confirm that person holds a current BP registration.
Learn more about builder licensing across Australia on the builder trade page.
WA Home Indemnity Insurance
Home indemnity insurance is one of the strongest consumer protections available when you hire a licensed builder in Western Australia for residential work. Understanding the requirements will help you make informed decisions.
Threshold: Home indemnity insurance is required for all residential building work valued at $20,000 or more. This applies to new builds, renovations, and extensions. It does not apply to associated work done on its own (swimming pools, carports, pergolas, sheds, fencing, or landscaping as standalone projects).
When it must be in place: The builder must take out home indemnity insurance and provide you with the certificate of insurance before accepting any payment or commencing any work. This is non-negotiable under the Home Building Contracts Act 1991.
What is covered:
- Incomplete work if the builder dies, disappears, or becomes insolvent
- Defective work where the builder has died, disappeared, or become insolvent
- Work that does not meet the contracted specifications under those same circumstances
What is NOT covered:
- Work performed under an owner-builder permit
- Normal wear and tear
- Damage caused by the homeowner
- Associated work done as a standalone project (pools, sheds, fencing)
- Work below the $20,000 threshold
Penalties for non-compliance. A builder who does not take out home indemnity insurance as required can be prosecuted and fined up to $50,000, and may risk losing their builder registration.
The builder must give you a copy of the certificate BEFORE work starts. Do not let anyone pick up a tool or accept a deposit until you have this document. If a builder says the certificate will come later, treat that as a serious red flag.
WA Contract Requirements and Deposit Limits
Western Australia has specific rules about building contracts under the Home Building Contracts Act 1991. These protections exist to prevent homeowners from being exposed to unfair contract terms. When you hire a licensed builder in Perth or anywhere else in WA, these rules apply.
Deposit Limits
| Contract Value | Maximum Deposit |
|---|---|
| $20,000 and above | Maximum 6.5% of the contract price |
Any builder who asks for more than 6.5% is breaking the law. If someone requests 20% upfront, walk away and report them to DEMIRS.
Cooling-Off Period
WA does not have a statutory cooling-off period for building contracts. Once you sign, the contract is binding. This makes it especially important to take your time reviewing the contract, getting independent legal advice, and making sure you are happy with every term before signing.
Fixed Price Contracts
The Home Building Contracts Act requires that building contracts be fixed price. Rise and fall clauses (where the price can increase due to material cost changes) are generally not permitted. This protects you from unexpected cost blowouts after signing.
Progress Payments
Progress payments must only be for work that has actually been completed or materials that have been purchased and delivered to site. A builder cannot invoice you for a stage that has not been finished. You have the right to inspect work before paying each progress claim.
Mandatory Contract Inclusions
Under WA law, your building contract must include:
- Builder’s registration number
- Full scope of work to be performed
- The contract price (fixed price)
- Start and completion dates
- The deposit amount (within the 6.5% limit)
- A progress payment schedule
- Home indemnity insurance details
- Dispute resolution procedures
- Details of any prime cost items and provisional sums
A written contract is mandatory for building work over $20,000. Verbal agreements leave you completely exposed. For more advice on contracts, read the complete guide to getting quotes from tradies.
How to Get and Compare Quotes in Western Australia
Getting multiple quotes is standard practice. Aim for at least 3 written quotes before deciding who to hire as a builder in WA.
What a Western Australia builder quote should include:
- Builder’s full name and DEMIRS registration number (BC number)
- ABN (Australian Business Number)
- Detailed scope of work
- Itemised pricing for each stage or component
- Prime cost items and provisional sums clearly listed
- Timeline with start and completion dates
- Inclusions and exclusions stated clearly
- Payment terms and schedule
Comparing quotes the right way: Compare like-for-like. One Perth builder may quote $450,000 while another quotes $380,000, but the cheaper quote might exclude site works, landscaping, and driveways. Always read the inclusions and exclusions before comparing the bottom line.
Ask each builder:
- What is your DEMIRS registration number and type?
- Can you provide your home indemnity insurance certificate?
- Who is the nominated registered building practitioner supervising my project?
- Can I speak with two recent clients?
Watch out for provisional sums. The Home Building Contracts Act requires builders to quote the minimum reasonable amount for provisional sums and prime cost items. A builder who loads up on inflated provisional sums may be hiding the true cost. Get clarity on every line item.
For a deeper breakdown, check out the guide on how to read and compare trade quotes in Australia.
Red Flags When Hiring a WA Builder
DEMIRS and the Building Commissioner deal with building complaints regularly. The warning signs are well documented. If you spot any of these when trying to find a licensed builder in Western Australia, proceed with extreme caution or walk away.
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Asking for cash payments to avoid GST. This is tax fraud, and it means there will be no paper trail if something goes wrong. No receipt, no recourse.
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No registration number on advertising or quotes. Registered builders should display their DEMIRS registration number on all marketing materials, quotes, and contracts. If it is missing, ask why.
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Unwilling to provide a home indemnity insurance certificate. If they dodge this request, they either do not have insurance or are not properly registered. Do not proceed.
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Only holds a BP (building practitioner) registration. Remember, only a BC (building contractor) can contract for building work. A BP cannot legally enter into a building contract with you.
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Quote significantly below all other quotes. If one quote is 30-40% cheaper than the rest, the builder is either cutting corners, underquoting to win the job, or not including everything.
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No fixed business address or ABN. A legitimate building contractor has a registered business address and an active ABN you can verify on the ABR website.
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Cannot provide references from recent clients. Every established builder should be able to give you contact details for at least two recent clients. If they refuse, something is off.
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Wants a deposit above 6.5%. The Home Building Contracts Act caps deposits at 6.5% of the contract price. Asking for more is illegal.
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Pressure to sign the contract immediately. Since WA has no cooling-off period, take your time. Any builder who pressures you to sign on the spot is a red flag.
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History of DEMIRS or SAT actions. Check the DEMIRS register and SAT decisions database for any enforcement actions. A pattern of complaints or disciplinary actions is a dealbreaker.
Owner-Builder Permits in WA
If you are considering managing the build yourself rather than hiring a builder in WA, you will need an owner-builder approval for domestic building work.
How to apply: Owner-builder approvals are issued by the Building Services Board through DEMIRS. You must complete an approved owner-builder course before applying.
Key things to know:
- Owner-builder course required. Unlike some states, WA requires you to complete an approved owner-builder education course before you can obtain owner-builder approval.
- Home indemnity insurance. As an owner-builder, you must obtain owner-builder indemnity insurance to protect future buyers.
- Disclosure requirement. If you sell the property within 7 years of completing owner-builder work, you must disclose this to the buyer. Failure to disclose can result in legal action.
- All subcontractors must still be registered. Every trade you engage must hold current registration for their work type. You cannot use unregistered subbies just because you are an owner-builder.
- You are responsible for safety. As an owner-builder, you take on all workplace health and safety obligations on site.
- Building permit still required. Owner-builders must still obtain building permits through their local council.
Owner-building can save money, but the responsibilities are significant. For a full breakdown, read the owner-builder permits guide.
What to Do If Something Goes Wrong: Building Commissioner and SAT
Even with thorough preparation, building projects can go wrong. Western Australia has a structured dispute resolution process through the Building Commissioner and the State Administrative Tribunal (SAT). Knowing the steps helps you act quickly.
Step 1: Raise the issue directly with the builder in writing. Put your complaint in an email or letter. Describe the problem clearly, reference your contract, and give the builder a reasonable timeframe to respond. Keep copies of everything.
Step 2: Contact the Building Commissioner. If the builder does not respond or you cannot reach a resolution, contact Building and Energy (part of DEMIRS). The Building Commissioner provides complaint resolution services as an alternative to court proceedings. They can investigate complaints about faulty or unsatisfactory building work and breaches of home building work contracts.
Step 3: Building remediation orders. The Building Commissioner has the power to issue building remediation orders requiring the builder to fix defective work. These orders are legally binding. If a builder fails to comply with a remediation order, they face further penalties including potential loss of registration.
Step 4: State Administrative Tribunal (SAT) for unresolved disputes. If the Building Commissioner’s process does not resolve the issue, you can apply to the State Administrative Tribunal (SAT). SAT can hear building disputes and has broad powers. For registered builders, SAT can order work or payments in any amount. For unregistered persons, SAT can order payments of up to $500,000. Applications for review must be made within 28 days of the Building Commissioner’s decision.
Alternative: Courts. You can also take building disputes to the Magistrates Court (claims up to $75,000) or the District Court (larger claims). However, the SAT process is generally faster and less formal.
For detailed advice on handling disputes across all states, read the building disputes guide.
How Much Does a Builder Cost in Western Australia?
Builder costs in Western Australia vary depending on the project type, location, site conditions, and finish level. Here are typical ranges to help you budget before you hire a licensed builder in Western Australia.
Common Project Costs in WA
| Project Type | Typical WA Price Range |
|---|---|
| New home build (standard) | $1,600 - $2,800 per sqm |
| New home build (premium) | $2,800 - $4,000+ per sqm |
| Full renovation | $1,200 - $3,200 per sqm |
| Kitchen renovation | $18,000 - $50,000 |
| Bathroom renovation | $12,000 - $35,000 |
| Granny flat | $100,000 - $200,000 |
| Deck or pergola | $8,000 - $30,000 |
| Home extension | $2,000 - $3,500 per sqm |
Hourly Rates
General builder hourly rates in Western Australia typically sit between $55 and $95 per hour, though this varies by region and experience. Perth metro rates tend to be higher than regional WA. Most builders prefer to quote on a fixed-price basis for larger projects, which is also the legal requirement under the Home Building Contracts Act.
Factors Affecting Price
- Location. Perth metro builders tend to charge more than regional WA builders due to higher overheads. Coastal suburbs and the western suburbs attract a premium.
- Site access and conditions. Sandy soil (common in Perth’s northern suburbs), limestone, sloping blocks, or difficult access require extra work and cost more.
- Material choices. Brick and tile is traditional in Perth and generally cheaper than rendered construction. Standard fittings cost less than premium selections.
- Market conditions. WA’s building market is heavily influenced by the mining sector. During mining booms, trade shortages push prices up. Always get current quotes to understand the real WA builder cost for your project.
For more cost breakdowns, browse the full range of cost guides on TradieVerify.
Frequently Asked Questions
Do I need a registered builder for all building work in WA?
No. A building contractor registration is required when the total cost of building work exceeds $20,000 including labour and materials. Below that threshold, registration is not mandatory for the contractor, though you may still choose to hire a registered builder for quality and accountability. Structural alterations should always be done by a registered professional regardless of cost. Check the WA state page for more details.
How do I verify a DEMIRS builder registration is current?
The fastest way is to search on TradieVerify, which cross-references DEMIRS data and shows registration status and type. You can also search directly on the DEMIRS Online Licence Search at ols.demirs.wa.gov.au. Always run a WA builder registration check before signing a contract.
What is the maximum deposit a WA builder can charge?
The maximum deposit under the Home Building Contracts Act 1991 is 6.5% of the contract price. Any builder who asks for more is breaking the law. Report excessive deposit requests to DEMIRS.
What does home indemnity insurance cover in WA?
Home indemnity insurance in WA protects you against incomplete and defective work if the builder dies, disappears, or becomes insolvent. It applies to residential building work valued at $20,000 or more. The builder must provide the insurance certificate before accepting any payment or starting work. It does not cover work done under an owner-builder permit or normal wear and tear.
Is there a cooling-off period for building contracts in WA?
No. Western Australia does not have a statutory cooling-off period for building contracts. Once you sign, the contract is binding. This makes it important to review the contract thoroughly and get independent legal advice before signing.
How do I lodge a complaint about a WA builder?
Start by raising the issue with the builder in writing and allowing a reasonable time for response. If that does not resolve it, contact the Building Commissioner at Building and Energy (DEMIRS). The Building Commissioner can investigate, issue remediation orders, and refer matters to SAT. For more steps, see the building disputes guide.
What is the difference between a BC and BP registration?
A Building Contractor (BC) registration allows someone to contract directly with homeowners for building work and operate a building business. A Building Practitioner (BP) registration allows someone to supervise building work and be named on building permits, but they cannot contract directly with clients. You need a builder with a BC registration for your project.
Can I be an owner-builder in Western Australia?
Yes, but you must complete an approved owner-builder education course and obtain owner-builder approval from the Building Services Board through DEMIRS. You still need building permits, registered subcontractors, and owner-builder indemnity insurance. If you sell within 7 years, you must disclose the owner-builder work. Read the full owner-builder permits guide for details.
Sources
- DEMIRS — Online Licence Search: https://ols.demirs.wa.gov.au/
- WA.GOV.AU — Builders’ Registration: https://www.wa.gov.au/government/multi-step-guides/builders-registration
- Building Services (Registration) Act 2011 (WA)
- Home Building Contracts Act 1991 (WA)
- SAT — Building and Construction: https://www.sat.justice.wa.gov.au/B/building_and_construction.aspx
- Legal Aid WA — Building Disputes: https://www.legalaid.wa.gov.au/find-legal-answers/homes-and-neighbours/building-disputes
- Master Builders WA: https://www.mbawa.com
- Housing Industry Association WA: https://hia.com.au