Every home extension we design and build is fully covered by a number of legal contracts that protect all parties.

Preliminary Agreement

After you’ve seen and approved the design concepts, before you’ve signed the Contract, we will ask you to sign a Preliminary Agreement that allows us to commence detailing the project. Our Building Team will visit your home and fully inspect the site to ensure what is being agreed to in the final Contract is true, fair and reasonable. Our Engineers, Supervisor, Estimator and Draftsperson join the Designer to inspect the site looking for any potential problem areas so they are known before you sign the Contract. This may seem like a common sense approach, but sadly it is not practiced by all extension builders.

Fixed-price contracts

Duncan Thompson Extensions offer fixed price home extension contracts which include design, planning approvals and construction. The contract details everything, with costings, so there are no nasty surprises. We are only able to lock in a price that we will be commited to after our team has thouroughly inspected your house and after a preliminary agreement has been signed.

HIA Building Contract

After the Preliminary Agreement is completed and before any work is commenced onsite we will get you to sign a Contract that is supplied by HIA (Housing Industry Association). The HIA New Homes, Alterations, Additions and Renovations Contract is legally binding and specifies all details of the build – design, detailed plans, timelines and costs.

Do I need a lawyer to check these contracts?

The contracts that we use have been prepared by the Housing Industry Association (HIA) and have been rigorously scrutinised by various government bodies and previously by many of our clients. Duncan Thompson Extensions has used this contract for over 25 years. That said, as for any large financial transaction you may have a lawyer look over the contract documents if you wish.

Related Information

Home Extension Costs

One thing almost everyone wants to know is how much a home extension costs. This is a difficult question to answer, but here we explain what factors determine the cost of an extension.

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There are a number of factors outside of our control, however we’ve completed so many over the last 30 years that we have a pretty good idea how long it takes to build an extension.

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We offer fixed-price home extension contracts which include design, planning approvals and construction. The contract details everything, with costings, so there are no nasty surprises.

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Project Management

Your Building Supervisor will be onsite every step of the way to ensure everything runs smoothly. They are your day-to-day contact and will facilitate any requirements you may have.

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Building Inspections

During every home extension a series of inspections are carried out to ensure all aspects of the construction have been implemented safely and within mandatory building requirements.

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Our people, from the front office right through to the onsite trades have worked with us for many years. This continuity of people ensures a smooth workflow during every extension we build.

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Building Permits

We’ll determine what permits and planning approvals are required to build an extension to your home. We negotiate with Councils on your behalf so there’s nothing you need to do.

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Building Insurance

Every home owner should ensure they have adequate insurance on their home before they start an extension. We can assist you if you have concerns about your level of cover.

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