Our kit price is a fixed number. The ground it lands on is not, and that is where budgets get away from people.
We supply the kit and the engineering. We do not do earthworks, slabs, service connections or driveways, and we do not quote them. What we can do is tell you what those items commonly run in Australia, so you can put a realistic number in your own budget before you fall in love with a design. Treat everything below as a be aware estimate, not a quote. Your site, your soil and your council decide the real figure, and the only price we commit to is the kit.
1. The soil test and site classification
Before anything is designed properly, the ground gets classified under AS 2870, from Class A through to P. That single letter drives your slab, your footings and a good part of your budget.
As a guide, a residential site classification runs about $400 to $1,500, with most flat suburban blocks at the lower end and rural or acreage blocks commonly $1,000 to $2,500 because of access and the number of boreholes.
It is the cheapest report you will buy and the one that prevents the nastiest surprise. Get it before you commit to a site, not after.
2. Earthworks, the cut and the fill
This is the big variable, and it is the reason two identical buildings on two blocks in the same street can be tens of thousands apart.
Published Australian guides put site preparation at roughly $10,000 to $25,000 on a flat suburban block, $25,000 to $50,000 on a moderate slope, and $50,000 and up on steep or difficult sites. Rock is its own category: an NSW civil contractor’s 2026 rate card puts a 600 square metre block at $8,000 to $25,000 in soil, and $20,000 to $65,000 or more where there is significant rock.
What moves that number: slope, rock, how far the spoil has to be carted, whether fill has to be imported and compacted, retaining, and whether a truck and a crane can actually get to where the building goes.
3. The slab
The slab is usually the single biggest item after the kit itself, and its price is set by that soil classification more than by its size.
As a guide from 2026 Victorian pricing, a house slab on a moderately reactive Class M site runs about $110 to $180 per square metre, and on a highly reactive Class H1 or H2 site about $150 to $240 per square metre. Every step up the reactivity scale typically adds 10 to 25 percent through deeper edge beams, heavier steel and more fill.
Two things worth knowing. A shed slab and a house slab are not the same slab, and a house slab under a Class 1A building has to be designed and certified for it. And as a rule our buildings bolt down onto the finished slab, so the slab can be poured and then the building set out on it. Where building height or wind speed push the holding down loads up far enough, cast in bracketry becomes unavoidable, and that is the exception rather than the rule. If your building is one of them, we will tell you at design stage, because those brackets have to be set before the pour and your concreter needs our drawings in his hands well before he books the truck.
4. Power
If the block already has a connection point, this is straightforward. If it does not, this is the item that shocks people.
A Victorian network’s own indicative price list gives a sense of the spread: a cable and pit off an existing overhead line up to 10 metres about $6,500, the same up to 50 metres about $17,800, a single phase rural substation on an existing pole about $30,000, and a high voltage overhead extension of up to 250 metres with a substation about $60,000. Those are 2024 figures from one distributor, and your network and distance will change them, but the shape of it holds: metres of line and whether a transformer is needed are what drive the cost.
Ask your distributor for an indicative connection cost early. It is free to ask and it can change which part of the block you build on, or whether you go off grid instead.
5. Water and wastewater
On a serviced block, published guides put a water service connection at roughly $1,500 to $4,000 and a sewer connection at roughly $3,000 to $10,000, with an extension of the main to reach you anywhere from $5,000 to $20,000.
Off the sewer, you are installing your own system, and 2026 Australian guides put a conventional septic tank with absorption trenches at about $8,000 to $15,000, an aerated wastewater treatment system at about $12,000 to $22,000, and a sand filter or mound system, used where the soil or water table rules out the others, at $18,000 to $30,000.
The part people miss is the ongoing cost. An AWTS carries a mandatory quarterly service contract as a condition of its approval, commonly $400 to $600 a year, plus the power the aerator draws. A septic tank has no service contract but needs a pump out every few years. Over twenty years that difference is real money, so weigh it while the council will still approve either.
6. Access, the driveway and the crossover
Two separate jobs. The crossover is the bit between your boundary and the road, and the council controls its specification, its approval and its inspection. Published guides put a standard concrete crossover at roughly $1,200 to $2,200. The driveway inside your boundary is yours, and gravel driveway work is commonly quoted around $28 to $45 per square metre, more where there is clearing, rock or drainage.
Before any of that, there is a question that costs nothing to ask and plenty to get wrong: can a semi trailer get to the building site and turn around? Your kit arrives on a truck. If it cannot get in, something has to be craned or double handled, and that is a cost nobody put in the spreadsheet.
7. Council, certification and the rest
Approvals, certification, engineering for anything unusual, stormwater, a bushfire or flood assessment where an overlay applies, and a water tank where the council requires one. None of these are large on their own. Together they are not nothing, and they vary more between councils than between states.
How to use these numbers
Do not add them all up and panic. Most blocks do not trigger most of this. A flat, serviced suburban block with good soil is at the bottom of nearly every range above. A sloping rural block with rock, no power at the boundary and no sewer is at the top of nearly all of them, and that is a different project with a different budget.
The honest way to handle it is this. Get the soil test. Ask the power distributor for an indicative figure. Ask the council what it requires. Get one local excavator to walk the site. That is four phone calls, it costs very little, and it turns the whole list above from a worry into a number.
Then put our kit price beside it, because ours is the part that does not move.
Our kit prices are published, per model and per square metre: shed house plans and prices. For what a finished build tends to cost, read how much does a shed home cost in Australia. For soil classes and footings in detail, see soil test and footing classification. For approvals, see building approvals. To lay out your own building and see it in 3D, start your design.
Brian Best
Founder & Builder
