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    Understanding the costs for your knockdown rebuild custom project.


    When it comes time to budget for your custom knockdown rebuild project, seeking expert advice is an invaluable step towards a seamless and less stressful building journey.

    Our experience with the changing needs of suburban living is a vital component of our success. Our understanding of the surroundings allows us to make a customer's investment go further, from home types to council standards and regulations. 


    What are site costs?


    Site costs relate to works needed to be carried out to create a suitable building platform for the project which is compliant with the relevant authority (Council or CDC) as well as the building code. 

    Specialising in knockdown rebuild projects we understand every site and every council are different. Beware that not all building quotes include your site costs – we highly recommend that if you find yours doesn’t, you should allow at least an additional 30% for unknown site costs.

    Levelling out your land if it’s a sloping block:  Excavation i.e earthworks and removal of soil or import of fill. 

    Zoning requirements for bushfire, flood, environmental and heritage-listed blocks. 

    Service connections for stormwater and hydraulic design, sewer connection and private electrical pole.

    Acoustic requirements (if applicable) for control of airport noise and/or management of roadside noise. 

    Slab type, some areas of Sydney have large amounts of clay in the soils that can require a thicker or stronger slab. 

    Acid sulphate soils are typically found when building on coastal areas. If not detected and treated correctly, when disturbed acid sulphate soils generate large amounts of sulfuric acid, iron and aluminium which can cause major damage to the environment and infrastructure i.e. damage to steel and concrete structures.

    During construction, trees are frequently harmed and even destroyed. However, with little forethought and consultation with a skilled arborist in the early stages, you can minimise damage and enjoy your trees for many years to come. A tree’s root structure can travel a long way and is integral to its health and survival and therefore must be properly accounted for. 

    Changing the location of services and connections for gas, water, NBN.

    Traffic control measures are implemented to ensure the safety of both workers and the general public during construction activities that may impact traffic flow. 


    Material handling covers many site-specific elements some being things such as overhead powerline protection (tiger tails), shade cloth to second-storey scaffolding when close to neighbours, split deliveries on sites with tighter setbacks, additional crane allowance when dealing with overhead powerlines, trees, tighter sites or a combination of all three. Complexity around slope and access to the site for our tradespeople.

    The demolition of the existing home plus rubbish and asbestos removal (if applicable).


    Your final price will be dependent on your site conditions, materials used in your build, demolition and internal fixtures and fittings. Generally, on a standard level block the average price per square metre can start from $3,500  for a custom-built home.

    Yes, rock is generally the only site cost which remains an allowance when the building contract is finalised.

    Yes. This is organised by the owner. You will need to engage the services of a licensed and insured Demolition Contractor as once demolition is complete, we will require a Clearance Certificate. Alternatively, we can put you in contact with our preferred demolition company which can explain the full process to you.

    • The average cost for demolition of your existing home in Sydney can start from $30,000 and generally takes approximately 7 days (weather permitting.)  However, it is strongly recommended that you work with your preferred company to book demolition in early, especially when considering a pool. Demolition costs vary with the size of the house and costs include: 

      • Access to site

      • Hazardous/asbestos removal (if required) Non-professional practice is often an attempt to save substantial tip fees by burying asbestos and other dangerous materials under the site. Your building site would then become a hazardous area and could cost you thousands to clear it up

      • Rubbish removal. Tip and recycling fees 

      • Established fencing between you and your neighbours. You will need to review whether it needs to be removed, which could become a shared cost

      • Council or independent certifier costs to approve the demolition which ranges from $800 - $1,500

    No. If you have established trees on your property which need to be removed, you may need to apply for a permit from your local council. This needs to be done before we can access your site to begin construction

    Yes. This would be dependent on your council. Factors that can influence these costs are: 

      • Different foundation often result in using bearers and joist construction for flood zones 

      • External materials (BAL rated front entry doors, aluminium mesh screens) to coincide with the Australian standards for bushfire zones  

    When you engage Hall & Hart alongside our trusted consultants, we will provide accurate guidance and estimates for these additional costs. When design decisions are approved and finalised, we fix these costs.  If you proceed to request a project quote, we can provide what these costs are after we complete a thorough site inspection of your block and apply for the 10.7 Certificate.

    At Hall & Hart Homes we want to ensure we are giving you the true cost of building your dream home which is why you will sign your building contract: 

    • AFTER you have signed off on your internal and external selections 

    • AFTER your plans have been approved by the authority (Council or CDC) and

    • AFTER we issue your Home Owners Warranty and Construction Certificate. It is then we require a 5% Contract Signing Fee.  

    We give you every opportunity to design the home you want before you are required to sign your contract, ensuring there are no hidden costs along the way. 


    Navigating knockdown Rebuild budgets.


    Embarking on a knockdown rebuild project involves a delicate balance between expenses tied to your property’s physical site and those that result from your design choices.



    No obligation cost estimates. Talk to our experts for your path to realistic knockdown rebuild budgeting.



    The best way to get a realistic assessment of how much your knockdown and rebuild will cost is, when the time is right, visit our display homes and speak to our highly experienced Sales and Design Consultants who will provide you with a no-obligation sales estimate.

    All of our Sales and Design Consultants are knockdown rebuild specialists and can give you sound advice. Using advanced technology, they will site your preferred design on your block of land and give you the true estimate to build your forever home.