Articles
Guides on geotechnical assessment, soil classification, flood and terrain data and site investigation for Australian property.
How to read a section 10.7 certificate for ground hazards NSW
A step-by-step walkthrough of reading a NSW section 10.7 planning certificate for acid sulfate soils, landslip, filled land and flood before you buy.
27 September 2026Landslip hazard in Tasmania: council map vs report
Comparing three ways to check landslip hazard on a Tasmanian block: the LIST hazard map, a council certificate and a desktop report before you buy.
24 September 2026Form 1 and site conditions in SA: 7 geotech mistakes
Seven mistakes buyers and builders make with soil, fill and reactive clay before a soil test in South Australia, and what a Form 1 does not tell you.
24 September 2026Queensland storm tide maps and sea level rise: what they show
What Queensland storm tide maps show: SPP high and medium hazard areas, the NDRP 20, 100 and 1000 year ARI mapping, and tide gauge sea level projections.
24 September 2026How to find out if a house has flooded before: public records
How to find out if a house has flooded before: recorded flood extents, historic flood lines, council flood records, and what they can and cannot show.
24 September 2026Flood certificate vs flood model report: what each tells you
Flood certificate vs flood model report: the council's adopted flood level for one event, versus modelled depth, velocity and level for every event.
23 September 2026Is a house under a flight path? How to check an address
How to check whether a house is under a flight path: ANEF contours, Airservices and airport flight path tools, and how often and how low aircraft pass.
22 September 2026Screening a Newcastle listing: flood, slope and zoning
A worked example of screening a Newcastle listing for flood history, ground elevation, slope and LEP zoning before you book an inspection in NSW.
22 September 2026ELVIS vs a clipped CAD-ready export for site elevation data
ELVIS gives free LiDAR and DEM data as whole tiles to merge, clip and reproject yourself. What that involves, and when a clipped site export is quicker.
20 September 2026How to read a QLD flood model report: a checklist
A checklist for reading published Queensland flood modelling for one property: depth, velocity, hazard, flood level, AEP events and floor levels.
17 September 2026Getting Tasmanian LiDAR contours and cadastre into Civil 3D and QGIS
A step-by-step walkthrough for exporting Tasmanian elevation, contours and cadastre and importing them into Civil 3D, QGIS or ArcGIS for site set-up.
16 September 2026Adelaide soil types by suburb: what is under your block
The geology under each part of Adelaide, what plains clay, beach sand and Hills rock mean for a build, and why a map alone cannot give a site class.
16 September 2026Adelaide Hills: what the bushfire and flood overlays actually say
Every Adelaide Hills suburb is in a bushfire overlay and most have no flood mapping. What the Planning and Design Code overlays mean for a Hills block.
16 September 2026Sea level rise for an address: what the tide gauge projections say
Projected sea level rise near an Australian coastal address by 2050 and 2100, where the IPCC AR6 tide gauge figures come from, and what they miss.
15 September 2026Adelaide expansive clay: 5 site classification myths
Five common beliefs about AS 2870 site classification on Adelaide's reactive clay, tested against measured Hs, ys and Iss values for the Adelaide Plains.
10 September 2026Buying a coastal lowland lot: a due diligence walkthrough
A worked example of due diligence on a hypothetical coastal lowland lot in NSW: what to check for flood, acid sulfate, zoning and Form 2 gaps, in order.
8 September 2026Reading groundwater bore logs: 7 common mistakes
The seven mistakes engineers and buyers make reading bore logs and standing water levels, from perched water to single-day readings, and what to do instead.
3 September 2026Site inspection or online risk check: what to do first
Comparing a physical inspection against an online flood and terrain risk check before you inspect, and which order saves you wasted weekends.
31 August 2026Site data checklist: before you start the design model
A step-by-step checklist for civil engineers and surveyors: gather, check and export contours, cadastre and elevation before building the first design model.
31 August 2026Soil test cost by state: QLD, NSW, VIC, SA and WA
What a residential soil test costs in each state in 2026, why the base price barely moves between capital cities, and what geology and travel add to a quote.
31 August 2026Geotechnical assessment cost: what is in the quote
What each line item in a geotechnical quote pays for, why two quotes for the same block differ by a factor of two, and what a quote must state to compare it.
31 August 2026How to get a geotechnical report: who to call, what to ask
Who writes a geotechnical report, when to commission one, what to send with the request, what the quote has to state, and what to check when it arrives.
29 August 2026Contaminated land check before you buy: NSW, VIC and QLD registers explained
How to check a property against the NSW EPA record, Victoria's Priority Sites and Queensland's EMR/CLR, and what a clear search still does not tell you.
29 August 2026Development applications near a property: how to check
Where to find the DAs lodged on a lot, next door and in the street in QLD, NSW, VIC, SA, ACT and TAS, and how to read their status, dates and plans.
27 August 2026Due diligence on a sloping infill block: a worked example
A worked example of property due diligence on a sloping suburban infill block in QLD: what to check, in what order, and what each finding changes.
26 August 2026Site classification and slab cost: Class M, H1, H2 and P
What an AS 2870 site classification means for slab design and cost, what puts a site in Class P, and what can be established before the soil test.
26 August 2026Geotechnical due diligence for a development site
A stage-by-stage geotechnical due diligence checklist for development sites: what to check before the offer, during due diligence, and at tender.
26 August 2026Building on reactive clay: decisions before the soil test
What reactive clay does to a house, and the footprint, floor level, plan shape, tree and drainage decisions made before the site classification arrives.
26 August 2026Depth to bedrock: how to check rock risk before excavation
How to assess depth to bedrock and rock excavation risk from mapped geology, nearby bore logs and terrain before drilling, and what it cannot settle.
24 August 2026How many boreholes does a house block need?
How many boreholes an AS 2870 site investigation needs, how deep and how far apart they should be, and six common beliefs that do not hold.
23 August 2026Site classification in Brisbane and South East Queensland
Why site classifications in Brisbane, Ipswich, Toowoomba and the coast come back M, H or E, and how fill and climate zone change the letter.
23 August 2026Uncontrolled fill: how to tell if a block has it
What uncontrolled fill is, how much AS 2870 tolerates before Class P, what it does to footing cost, and how to spot filled ground from records.
23 August 2026Why the same clay classifies differently in Sydney, Melbourne and Adelaide
Climate zone sets how deep the ground dries each year, which changes the AS 2870 letter for identical clay. How Sydney, Melbourne and Adelaide differ.
22 August 2026Brisbane flood check by address: how to screen a listing before you inspect
How to check any Brisbane address for flood risk - the council Flood Awareness Map, the FloodWise report, lot overlays, and a ten-second check while you browse.
22 August 2026Chrome extensions for realestate.com.au: flood, zoning and elevation on every listing
What a realestate.com.au browser extension can do for Brisbane buyers, what to check before installing one, and how Scout reads every listing you open.
17 August 2026Council flood map or ground elevation? Two ways to check flood risk on a listing
Comparing the two things buyers rely on to judge flood risk online: the council flood overlay and the actual ground elevation. Which to trust, and when.
13 August 2026Eight mistakes people make importing site data into Civil 3D, QGIS and ArcGIS
The specific errors that break contours, cadastre and elevation imports in Civil 3D, QGIS and ArcGIS - and how to set up a clean site early.
10 August 2026Check a property for a heritage listing before you buy
A step-by-step walkthrough for checking heritage and character controls on a property in QLD, NSW and VIC before you make an offer, register by register.
6 August 2026Six myths about AS 2870 site classification, and what's true
M, H, E and P classes explained through the myths that trip up builders and owner-builders. When a soil test is enough, and when it isn't.
3 August 2026A coastal lowland lot on realestate.com.au: reading the risk before you inspect
Follow one hypothetical coastal lot from listing to decision, showing exactly what flood, slope and terrain clues to read online before you book an inspection.
1 August 2026.12da and .12daz files: what they are and how to open them
What a 12d Model .12da or .12daz archive contains, the difference between them, and every way to open one - including two free options that need no 12d licence.
1 August 2026What does 12d Model cost? And do you need a licence just to read a 12d file?
12d Model pricing in Australia: why there is no published price, what drives the quote, the 15% annual maintenance, and the free two-month licence few mention.
30 July 2026Contours or DEM? Choosing between vector contours and raster elevation for site set-up
Vector contours versus GeoTIFF DEM raster for QLD, NSW and VIC site work: formats, resolution limits and workflow fit for Civil 3D, QGIS and ArcGIS.
27 July 2026Flood overlays versus actual flood risk: reading the mapping like a planner
Flood overlays, DFE, PMF and hydraulic categories all mean different things. A technical guide to reading QLD and NSW flood mapping and its real limits.
23 July 2026Bore logs and groundwater records: how to read them
How to find and read registered bore logs and groundwater records in QLD, NSW and VIC, what they show about a site, and where they mislead.
20 July 2026How to spot a steep or sloping block from a listing before you inspect
Learn to read slope and terrain risk on realestate.com.au listings before you inspect: the clues photos hide and what steep ground costs.
16 July 2026Getting cadastre and lot boundaries into Civil 3D and QGIS: DXF, Shapefile and GeoPackage
How to prepare QLD, NSW and Victorian cadastral boundaries and easements for Civil 3D, QGIS and ArcGIS in DXF, Shapefile, GeoPackage or KMZ.
13 July 2026Can you develop it? Checking planning limits before you buy in QLD and NSW
Before buying for a knock-down-rebuild, subdivision or duplex, learn how to check zoning, overlays and planning limits in QLD and NSW.
13 July 2026Sent a 12d file but don't have 12d? How to open .12da files in AutoCAD or BricsCAD
What's inside a 12d Model .12da or .12daz handover, and how to extract its strings and alignments as a layered DXF for AutoCAD, BricsCAD or Civil 3D.
9 July 2026Acid sulfate soils: classes 1 to 5 and how to check a site
What acid sulfate soil classes 1 to 5 mean in NSW and QLD, where the soils occur, what they change for footings and earthworks, and how to check a site.
6 July 2026How to check if a house is in a flood zone while you're browsing listings
A quick, plain-English guide to spotting flood risk on realestate.com.au listings before you inspect, without leaving the listing page.
6 July 2026How much does a geotechnical report cost? 2026 prices
How much a geotechnical report costs in 2026: desktop from $119, site classification from $700, full investigation from $3,000, and what moves the price.
2 July 2026Choosing the right contour interval: turning QLD and NSW LiDAR into usable design contours
How to choose contour intervals and smoothing for Australian government elevation data, then use clean contours and GeoTIFF DEMs in Civil 3D, QGIS or ArcGIS.
29 June 2026Easements explained: what those lines on the title mean before you buy
What an easement is, the common types in QLD and NSW, how to find them, and what they mean for what you can build before you buy a property.
25 June 2026Fill on a building block: what the records show
How to tell whether a block has fill before drilling, using historical aerial imagery, contours, geology and nearby bore logs, and what fill changes.
22 June 2026What listing photos hide: reading flood and ground clues before you inspect
Listing photos are styled to sell. Learn how to spot flood, slope and terrain risk on a realestate.com.au listing before booking an inspection.
22 June 2026Getting the coordinate system right: MGA2020, GDA94 and AHD for QLD, NSW and VIC site data
Set the correct CRS when importing QLD, NSW and Victorian contours and cadastre: GDA2020 and GDA94 MGA zones 54, 55 and 56, plus AHD.
22 June 2026Class P site classification: triggers, cost and meaning
What puts a site in Class P under AS 2870, the seven triggers, why P is under-reported, and what an engineered footing design adds to the build.
17 June 2026Property due diligence: the data is public, but scattered
Property due diligence in QLD and NSW means checking zoning, flood and bushfire data before you buy. Why it is scattered, and how to get it in one report.
11 June 2026We analysed 1.47 million South East Queensland lots. Here's where the ground is wet, steep, and low.
Lot-level data across Brisbane, Gold Coast, Moreton Bay, Logan and Redland: 1 in 4 lots intersect council flood mapping and 228,000 sit below 5 m AHD.
13 May 2026Reactive soils and building damage: causes and what to check
What reactive clay does to slabs and brickwork, why cracking follows dry and wet seasons, and what to check before building and after damage appears.
10 May 20261.2 million homes. A pipeline that isn't keeping up.
Australia has committed to 1.2 million new homes by 2029 and is already behind. Meeting the target means better decisions at every stage of development.
10 May 2026Geotechnical desktop study: what it covers and its limits
What a geotechnical desktop study covers, what it settles without drilling, what it must defer to a site investigation, and when to commission one.
10 May 2026Geotechnical report vs desktop assessment: the difference
What separates a desktop assessment from a full geotechnical report: what each covers, what each costs, and which one a decision needs.
10 May 2026Soil test cost in Queensland: $700 to $3,000+ in 2026
What a soil test and AS 2870 site classification cost in Queensland in 2026, what moves the price by region, and what a desktop report cannot do.
10 May 2026AS 2870 site classification: classes A to P explained
What each AS 2870 site class means from A to P, how ys, Iss and Hs decide the letter, and what can be known about a site before the soil test.