A site assessment is the survey and inspection that establishes what your block will actually allow. It costs a small fraction of a build and it is the difference between a quote you can rely on and an estimate that moves. Almost every unpleasant surprise in a building budget traces back to something a site assessment would have found.
What gets assessed
The contour, meaning the fall across the building envelope specifically rather than across the whole block, because that is what drives earthworks and footings.
The soil, classified from a geotechnical test, which determines the footing design and whether piers are needed.
Services. Where power, water, sewer and stormwater are, and how far they have to come.
Overlays and constraints. Bushfire, flood, storm tide, character controls, easements, setbacks and protected vegetation.
Access. Whether a concrete truck and a crane can reach where they need to be, which sounds trivial until it is not.
Aspect. Sun path and prevailing breeze, which are design inputs rather than cost inputs but get recorded at the same visit.
What it costs, and what it saves
[CONFIRM: typical cost of a contour survey and soil test in Brisbane]. Against that, a footing design based on a guessed soil classification, or an earthworks allowance set without a contour, can move a budget by tens of thousands. The assessment is not a cost, it is the thing that makes the rest of the numbers real.
The three things it most often finds
More fall than the block looked like it had, which changes the earthworks and sometimes the whole design approach. Reactive soil requiring a stiffer footing system than budgeted. And an overlay nobody mentioned, which changes the specification.
None of these are disasters when you find them before you sign. All three are expensive when you find them after.
Why some builders skip it
Because a quote off a floor plan can be produced in a day, and a quote off a survey takes weeks. If you are comparing two builders and one has a price for you immediately, ask what that price assumed about your soil and your fall. Then ask what happens to the price when the assumption is wrong.
How we handle it
We do not give a firm price without one. You get an estimate at concept stage built on what the block actually is, with site costs itemised rather than bundled into an allowance you will not understand until it is exceeded.
We build in North Lakes, Narangba, Newport, Samford Valley and Banksia Beach. Call 0483 949 127.
