The Truth About Site Works - House Designs Perth

The Truth About Siteworks Perth

Siteworks are the costs associated with how a Builder will attach your new home to the ground.

It is more than just Earthworks; a lot more.

Siteworks are also not included in the base price of any home. It is always on top of the base price of a home.



Every block of land is different. A Siteworks Provision for a block of land in Piara Waters or Aveley is going to be very different to the rock and clay areas of Kalamunda and Darling Downs.

A block of land in a Master Planned Community will also have different costs associated to it when compared building on a Subdivided In-Fill Block of land.

A Builder cannot accurately add these costs into a base price of any home. There are too many unknown factors to cost into the equation.

The most common items you are likely see in your Siteworks Provisional Sums are…

  • Survey Repeg
  • Earth Works
  • Engineering Detail
  • Retaining Wall Inspection
  • Storm Water Disposal or Soakwells
  • Water Connections
  • Sewer Connections
  • Power Connections
  • Phone Connections
  • Hard Digging
  • Shire Fees
  • Shire Bonds
  • Council Cross Over
  • Coastal Zone Allowances,
  • Bush Fire Attack Level (BAL) Provision
  • Tree Protection
  • Traffic Management
  • Reticulation
  • Concrete Pump
  • Energy Efficiency
  • Material Handling

There are of course plenty more items to consider.

If you are building in one of Perth’s Major Developers Land Estate most of these items will be known. If you are building in Brownfield Site then it can be a can of worms.

A Builder can not to look at a block of land and tell you what the final siteworks costs will be. The final costs will always be dependent upon the information that we cannot see.

It is important to note that no matter which Builder you choose to build your house, every single housing lot will have a siteworks component in addition to the construction component.


Siteworks Quotes are one of the most Misunderstood parts of a Build.


It is a condition of the Home Building Contracts Act 1991 for a Builder to give their best estimate for a siteworks amount. However this doesn’t always happen.


Why? Usually it is one of these two reasons.


1. The Builders Sales Representative simply doesn’t know what they are doing.


2. There are a surprising large amount of people that will actually base a lot of their building decision on a “cheap” siteworks quote. Builders Sales Representative know this. It is unfortunately quite common for unscrupulous Builders Sales Representative to give their client a “low ball” siteworks figure. They know that they can go back to the client later and ask for more money later in the process.

It is a bait and hook sales tactic.

By the time the Builders Sales Representative goes back to the unsuspecting client for $1,000s and $1,000s more, the client is so invested in the build that there is a very high likelihood that they will simply pay the difference. This is the amount they should have been quoted in the first place.

Often this is one of the earliest indicators of a horror build.




When paying my initial fee to the Builders Sales Representative can I expect that the siteworks will have been fully costed and fixed from a price point of view?



When a client signs the initial Pre Construction Contract or Pre Construction Agreement, a Builder the Sales Representative will only be able to provide the client with a siteworks estimate

The building industry refers to this Estimate as a Siteworks Provisional Sum Allowance. This estimate may itemise what the Builder is quoting for or simply state an amount that they have allowed.

It does not necessarily mean that they have allowed for all of the items that may eventually be required or that they have allowed enough for the cost of the works that will need to be completed.


What information does the Builder need in order to finalise my siteworks?


No Builder is able to confirm the actual siteworks cost until the Builder has at least been able to complete the following;

  • Contour Feature Survey
  • Engineers Report which includes a soil classification assessment and a wind rating assessment
  • Bush Fire Attack Level (BAL) report (if applicable)
  • Noise Attenuation Report (if applicable)
  • Energy Efficiency Report
  • Finished Floor Levels of the home
  • Confirmed compliance with all Local Shire related requirements

The building lot must be titled and fully completed by the developer before these items can be confirmed and therefore before the final costs can be determined.


BAL - House Designs Perth


What are the issues that could lead to a higher siteworks cost?


The following lot types or issues are just some of the common reasons why the siteworks cost will usually be higher than those applicable to a standard, flat, retained lot in a new sub division. For example, sites that;

• require retaining walls to be installed
• have an incline or decline to the garage
• contain traces of limestone, rock, clay or peat in the soil
• have a high water level table
• require vegetation to be removed
• are in High Wind areas
• are within 1000 metres of Breaking Surf
• are in Bushfire Attack Level (BAL) designated areas
• are subject to Noise Attenuation Requirements
• require the home to be upgraded from an Energy Efficiency point of view
• are defined as Semi-Rural
• are defined as Rear Strata or House Behind a House
• are in Brownfield areas (established areas)
• require scaffolding work due to height issues
• require piling due the house being built over an underground sewer
• require the Builder to remove an existing residence

Once the siteworks costs have been confirmed and if those confirmed costs are higher or lower than the estimated costs then you will be issued with a siteworks adjustment variation.

If the confirmed siteworks costs are less than your estimated costs then the credit owing to you will be given at your final progress payment. If the actual costs are higher than the original estimated costs then you will receive an invoice for the additional amount.



Coastal Zone - House Designs Perth


Can the siteworks amount change if I have already signed a Pre Construction Contract but have not yet signed the final Building Contract?



If you receive an invoice for additional siteworks costs at this stage of the process then you will have two options to select from;

Option 1:
Pay the siteworks variation amount and then proceed to construction.

Option 2:
You can also cancel your Pre Construction Contract.
Please note that you will most likely have to pay the costs associated with your job that are over and above the Pre Construction Contract Fee that you paid at the initial sign up stage.


Can the siteworks amount change if I have already signed a Building Contract?



On some occasions the client will require the Builder to sign contracts before all of the site investigative work can be carried out. This may be due to a deadline involving a Government Grant or the settlement of a House and Land Package.

It is important to understand that the signing of a Building Contract does not prevent the Builder from varying the contract price.

The Legislation that governs the Building Contract allows for the Builder to adjust the contract price should unforeseen information become available following the signing of the Building Contract.

The protection for the consumer is that if any extra cost results in the signed contract price increasing by more than 5% then the client has the right to exit the signed building contract.

The consumer must be aware that the Builder may be able to claim any additional costs over and above the initial Pre Construction Fee that they paid at the initial sign up stage.


If I have to pay any Shire related fees, can I pay those fees directly to the Shire?


With respect to shire related fees the client can pay the Shire directly. The client needs to be aware that they will need to fund these items upfront from their personal savings should they choose to remove it from the building contract.

The Builder will not submit the paperwork to the Shire unless these fees have been paid.


Is there such a thing as no site costs or free site costs?


In short – no. Some Builders or Builders Sales Representative may market this way but every home will have site related issues and there is a cost attached to those issues.

Some Builders may choose to make it a part of the house price by inflating the true house price. Or instead of offering a discount against the house – the Builder may choose to apply the discount against the siteworks itself.

Either way you are paying for it.


Can I do any of the site related items myself?


Yes. You can do some things yourself. Keep in mind that if you do then you will need the funds to pay for it up front, which can be a burden on your personal finances.

Most consumers include everything in the contract for three simple reasons;

1. The works is performed by the Builder and therefore guaranteed by the Builder

2. The items in the Building Contract will be financed by the loan and therefore the consumer doesn’t need to come up with additional monies to pay for the works

3. It is more convenient for all parties to have the works done by the Builder.


Should you wish to do any of the siteworks items then you will need to seek approval from the companies Building Construction Manager before you sign your initial Pre Construction Contract.


Who do I trust?


Online chat forums are notorious for mis-informed people providing so-called qualified comments. Often this misguided advice is damaging to the client’s position.

Unfortunately, many of these comments are provided by Builders Sales Representative who are trolling the online forums in search of a new prospective client.

If a Builders Sales Representative suggests that the siteworks price can be fixed at the initial sign up be on High Alert. Any such promise will be subject to conditions that will appear in paperwork at a future stage.


Does the Builder make a profit (margin) on siteworks?



Builders will apply a profit margin to every item in the building process. This referred to as the Builders Margin.



Like everything in Life…



If a Builders Sales Representative offers you a siteworks amount Significantly Different to other Builder Quotes, then get the Builders Sales Representative to commit to it in writing.

The following Form has helped out many of my clients get the truth.

It has also saved a lot of financial mis-adventure, heartache and anguish. Make sure that both the Builders Sales Representative and the Owner or General Manager of the Building Company they work for sign it.

If we can be of further assistance please Contact Us 



Download Here: Fact Sheet – Site Works in Perth Western Australia