This standard HIA contract outlines all key details of your building work, including costs, timelines, payment stages, and responsibilities, ensuring transparency for both the builder and the homeowner. It also defines how variations, delays, and disputes are handled, providing clear dispute resolution processes that protect both parties.
For homeowners in Western Australia, the HIA contract complies with the Home Building Contracts Act 1991 (WA), meaning your agreement meets all state requirements while offering an added layer of consumer protection.
At WOW Homes, we help first home buyers understand every part of the process, from finance approval to key handover, ensuring your building journey is simple and transparent.
What Does a HIA Contract Include?
A HIA contract covers every essential detail of your building project, from design to completion, ensuring both sides understand what is included, when payments are due, and what happens after handover.
Project Details and Scope
The contract begins with a description of the project details, including plans, building specifications, inclusions, and exclusions. This defines exactly what will be built, what materials will be used, and what finishes are included.
Anything not explicitly listed may not be part of the contract, so reviewing these documents carefully before signing is crucial.
Fixed Price and Allowances
Most fixed price contracts establish a total contract price before construction begins, giving homeowners cost certainty.
However, some components, known as Prime Cost items and Provisional Sums, are based on estimates.
- Prime Cost (PC) items cover materials not yet selected (like tiles or appliances).
- Provisional Sums (PS) account for uncertain work such as excavation or retaining walls.
If actual costs exceed the estimates, the owner must pay the difference plus the builder’s margin. These details are listed in the contract to ensure transparency about potential cost changes and the total contract price.
Payment Schedule
Payments are made progressively throughout the building process, based on progress payments tied to key construction stages.
The payment stage breakdown typically includes:
- Base
- Frame
- Lock-up
- Fixing
- Completion
Each payment is made after the corresponding stage is completed, giving both parties structure and accountability throughout the project.
Variations
If changes arise after signing, such as upgrades, design adjustments, or compliance updates, they’re treated as variations. All variations must be documented, signed by both parties, and include details about costs and timing impacts. This keeps the building contract transparent and avoids disputes over verbal agreements.
Extensions of Time
Construction can be affected by factors like weather, supply delays, or council approvals. The contract outlines when a builder can claim an extension of time, adjusting the completion date without penalty. This ensures both parties understand what qualifies as a valid delay and how these extensions are managed in writing.
Defects and Warranties
Once construction reaches practical completion, the homeowner enters the defects liability period, typically three to six months, where the builder must fix non-structural defects. Longer statutory warranties apply to structural elements, protecting owners against major issues for years after handover.
These warranty provisions ensure that any building work meets the agreed quality standards.
Types of HIA Contracts in Australia
There are several kinds of HIA contracts depending on the type and scale of your building projects:
- New Home Building Contract: Used for constructing a new home on vacant land. Explore our house and land packages across Perth to see how this type of contract applies to your build.
- Renovations and Additions Contract: For upgrading, extending or improving an existing property.
- Small Works Contract: Designed for minor residential work like decks or patios.
- Cost Plus Contract: Where you pay the actual cost of labour and materials plus a builder’s margin.
- Fixed Price Contracts: The total contract price is agreed upon at the start and remains unchanged unless an approved variation is made.
Why Builders Use HIA Contracts
Reputable builders across Australia, such as WOW Homes, rely on the HIA contract because it delivers a clear, standardised, and legally recognised structure for managing residential construction.
A Standardised Legal Framework
As one of the most widely used contracts in the Australian housing industry, the HIA building contract provides uniformity and compliance with national and state laws. It’s regularly updated to reflect legislative changes, offering builders and homeowners confidence that their agreement aligns with current regulations and industry standards.
Reducing Disputes and Misunderstandings
Many costly mistakes in home building occur when agreements aren’t clearly documented. The HIA framework mitigates this by outlining every detail, from progress payments to variations and extensions of time, so both parties understand their rights and responsibilities. This clarity significantly reduces the likelihood of conflict or legal obligation.
Compliance with Western Australian Legislation
In Western Australia, all HIA contracts comply with the Home Building Contracts Act 1991 (WA). This ensures transparency around payment schedules, fixed price contracts, and special conditions, while also protecting consumers from unfair contract terms. Builders must comply with these legal standards, providing further assurance for homeowners entering into residential building agreements.
Clarity and Accountability
The standardised structure of the HIA building contract promotes trust and efficiency. Homeowners know what they’re paying for, when each stage will be completed, and what recourse they have in the event of delays or disputes. Builders benefit from a streamlined workflow supported by predictable cash flow through progress payments.
Build Smarter with WOW Homes!
At WOW Homes, every new home is built under a trusted HIA building contract, so our clients can move forward with total confidence.
If you’re ready to begin your build or want expert guidance before signing your contract, get in touch with us today to start your new home journey with clarity and peace of mind.
Further Reading
What Is LMI and Can First Home Builders in WA Avoid It?