Site costs for house and land in Victoria: what they cover and how to get them in writing

Site costs are the work needed to get your block ready for the slab and connect it to services. Depending on the lot, that can include soil and slope work, excavation, fill, rock, retaining, drainage and service connections. Builders itemise them differently, so ask for a line-by-line list in writing.

Features of the land, such as slope and soil type, affect the design and cost of a build, according to Consumer Affairs Victoria. Two lots in the same estate can need different footings, fill or retaining, so a site cost quoted for one lot may not apply to another.

It depends on how the price is set out. A quote can show site costs as a fixed amount, as an allowance or provisional sum, or leave them out. Whoever you buy through, ask which site costs are fixed and which are allowances or provisional, and get the answer in the contract, not just the brochure.

They can if the work is a provisional sum or you agree to a variation. Under Victorian building law, price changes are limited to variations agreed in writing and to prime cost and provisional sum items, according to Consumer Affairs Victoria. CAV also says you shouldn't have to pay extra for problems, such as rock, that the builder should have identified from the foundation data. Check your contract and get legal advice if this comes up.

Before you sign, ask for the soil test for your specific lot, and whether a contour survey has been done too. Then ask for each site cost to be listed in the contract as a fixed amount rather than a provisional sum where possible. Consumer Affairs Victoria says to avoid provisional sums where you can, because they can make your final cost higher. Have a conveyancer or building lawyer review the contract.

Foundation data is information, including a report based on soil tests, that recommends the stump depth or the type of slab or footing for your lot. Consumer Affairs Victoria says your builder must get it by law before you sign the building contract. Builders usually arrange it, but you can also get it yourself through a designer or geotechnical engineer, which lets other builders quote on the same data.

Ask whether a soil test has been done for your lot, which site costs are fixed and which are provisional sums, what's excluded, and who pays if rock or extra fill is needed beyond the allowance. Then check the builder on the Building and Plumbing Commission register and get legal advice before you sign.