What we look for in Serpentine, and why it differs from the suburb next door. 46.8 km from the CBD, 20.6 km from the coast, postcode 6125.
Serpentine gives the shire its name but was never its biggest town. It is a rural district on the river of the same name, settled from 1893 and built on dairying. Its landmark is the cheese factory opened in 1932, which was then the only operating cheese factory in Western Australia.
That agricultural history is what an inspection actually meets. Properties here often come with old farm buildings as well as a house. Dairies. Milking and hay sheds. Stables. Sometimes a workers' cottage. Most of it built of early timber and corrugated iron, with some soft brick.
These are frequently unmaintained and sometimes unapproved, and they need to be assessed properly or explicitly excluded from the report. A buyer who assumes a shed is sound can inherit an expensive problem, and the sheds on a rural block are often worth more to the owner than the house.
The Serpentine River brings a flood context to the low river flats, along with alluvial soils and seasonally high groundwater near the water. Rural holdings here are generally unsewered, so confirming the effluent system, the water supply and the age of each matters as much as the house. With bushland and the Darling Scarp to the east, bushfire exposure is genuine, while the coast is far enough away that salt plays no part.
Rural properties are a different job from suburban ones, and the risk is spread across the whole site rather than concentrated at a house perimeter.
Old farm buildings are the concern. Timber framed sheds sitting directly on damp ground. Untreated posts set into soil. Stacked timber and old fencing. All of it provides established habitat close to the dwelling. Windbreaks and remnant vegetation hold colonies. Irrigation and stock water keep ground damp through summer.
The house itself may be timber floored, in which case the subfloor is the priority, or a newer slab built home where the perimeter matters most. Either way, agree in advance which structures on the property are included in the inspection.
On acreage the argument is time and travel. Getting an inspector to a rural block, walking the house and the outbuildings, and assessing services that are all private takes hours rather than minutes. Doing structure and timber pests in one attendance is the only sensible approach, and it means one person forms a view of how water and timber interact across the whole property. Reported under AS 4349.1 and AS 4349.3.
Rural subdivision and new housing on the flats bring building stage inspections and practical completion inspections. On rural blocks the site works, drainage and effluent system deserve attention while they are still visible.
We also do pre-settlement inspections, dilapidation reports where heavy works are happening nearby, and expert witness reports. On rural properties those usually concern drainage, boundaries, or a shed that turned out never to have been approved.
If you are buying acreage, agree the scope in writing before the inspection. Which buildings are included, and which are not, is the single most common source of misunderstanding on a rural job.
Serpentine sits on the Bassendean dune system — deep leached grey quartz sand, almost pure, and very free draining. Bassendean sand is about as unreactive as a building site gets, so seasonal footing movement is rarely the story here. The water table is the story. Parts of this system sit over the Gnangara Mound and the standing water level can be within a couple of metres of the surface.
What that means in practice, on a house in Serpentine:
Landform is assigned from the suburb's position on the Swan Coastal Plain rather than from a site soil test. It tells you what to expect, not what you have. A site classification to AS 2870 is a different exercise and a different report.
Mardella, Cardup and Oldbury sit on the same ground as Serpentine, so the footing behaviour and the drainage problems tend to repeat across all of them. If you are comparing houses across those suburbs, you are largely comparing the same site conditions.
Mundijong is 6.9 km away but sits on the Guildford Formation; Whitby is 9.0 km away but sits on the Guildford Formation; Keysbrook is 9.7 km away but sits on the Guildford Formation. That is the useful thing about this part of Perth: the ground can change inside a few kilometres, and with it what an inspection is looking for.
On site classification: any soil zone quoted for a suburb is indicative, inferred from geography rather than surveyed. A real AS 2870 classification comes from geotechnical work on your actual block and can differ from the one next door. We report what we observe; we do not read your soil class off a map.
The inspection is visual and non-invasive, over the readily accessible areas, reported to AS 4349.1. Our inspectors physically enter the roof space, as long as there is sufficient access. Report within 24 hours of the inspection.
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Flat fee, the same in Serpentine as anywhere: $440 inc. GST for a pre-purchase building inspection, or $616 inc. GST with the timber pest scope added in the same visit. Full price list →
Well inland at 20.6 km from the coast, out in Serpentine - Jarrahdale, the inland setting changes what the fee buys in Serpentine: footing and slab movement, drainage and the reactive soils of the South East belt come first, and coastal delignification is a lower priority away from the arterial corridors. Serpentine is 46.8 km from the Perth CBD, out toward the Peel end of the area, and the flat fee still applies with no distance loading.
Pre-purchase building inspection in Serpentine →
Building and pest inspection in Serpentine →
Yes. Our inspectors physically enter and inspect the roof space, as long as there is sufficient access to do so safely. Where access is restricted, the report says so plainly rather than implying we saw more than we did.
At 20.6 km inland, Serpentine carries lower coastal-salt exposure, so delignification is not the first thing we would expect. It remains possible near heavy arterial corridors or industrial emissions.
Within 24 hours of the inspection itself, not 24 hours from booking. On a pre-purchase or pre-settlement job that timing is the whole point, because your leverage disappears once you are committed.
We would rather you checked than took our word for it. These are the bodies that actually hold the records and set the rules:
Tell us about the property and what you need. We'll come back to you with a firm quote and a time.
PERTH