Site Costs

The following costs and information are indicative construction costs that are known as Provisional costs in the building contract. These costs vary according to layout of the house design and building site contours.

Calculating on site costs

Old house demolition

You should have an allowance of $15,000 - $20,000


The excavation of a site varies greatly. This is due to the site being a flat block or a steep site. There are different construction methods to tackle this challenge i.e. (Slab or bearers and joist).There may be requirement for retaining walls if a site is steep. We at Preston and Sons are able to provide solutions for these challenges with accurate estimates.

Site Access and roads

When a site is situated in a rural area often existing roads are not available. There may be a need for road building and road base material that would be compacted for suitable thoroughfare. We always include a sub base road for entry to sites so access will be available throughout the project. If bitumen sealing is needed Preston and Sons can arrange for this at the end of construction.


If purchasing new land the power that is available to the site should be assessed and deemed suitable/unsuitable for the new buildings. The level 3 ASP is the authority on power loading and will require an “application for connection of load” submission to Integral energy. The main Goal alongside the Basix report is to reduce energy consumption as much as possible and reduce the chance of a power upgrade requirement. If a power upgrade report is needed then an “electrical supply report” is needed which usually costs around $1,500.

Data/phone connections

If a phone line exists to the boundary of the site Telstra will install the cable required to the first point in the site free of charge if a trench is dug. If high speed ADSL is a requirement the exchange will need to be assessed.

Water supply

If on a rural block Preston and Sons can arrange for the installation of water tanks, either in ground concrete tanks or above ground poly/colorbond tanks. A Concrete in ground tank that holds 140,000 Litres costs approx $20,000.

Rural Dams

If an average size dam is required on your site then Preston and Sons have the excavation team that can complete it for you for around $8,000.

Sewage Treatment

Council will require a sewage effluent system if town sewer is not available. If in a Sydney catchment area which is most of Kangaroo Valley a specialised system will be required. Most systems will be a transference aerated in ground tank design. These are filtered systems that disperse the clean waste into sub filtered trenches below the building site. A system costs approximately $12,000 for a 3 bedroom house.


You may require rural fencing on your property for animal barrier or aesthetic purposes. Preston & Sons can organise a quote for the required fenced areas from local fencing contractors.

Outdoor living

There are many options for what we like to call outdoor living. Aussies love the outdoors and pools, bbq’s, landscaping, cabana’s, and shelters are our specialty. If you decide to include any of these options as part of your new home Preston & Sons are only too happy to provide prices for these requirements.

If you require us to organise fencing we will charge 15% or costs for organisational expenses. The job will be taken care of. All costs shown are not inclusive of 15% on costs of GST.

Once again you can be assured:

A job with Preston & Sons is a job “treated as our own”