Articles
Guides on geotechnical assessment, soil classification, flood and terrain data and site investigation for Australian property.
Geotechnical desktop study mistakes: 7 NSW pitfalls
Seven mistakes NSW builders and engineers make with geotechnical desktop studies: fill, acid sulfate soils, bore logs, section 10.7 and reactive clay.
10 November 2026Checking a bushfire overlay on a Victorian listing: a walkthrough
A step-by-step walkthrough to check the Bushfire Management Overlay and bushfire-prone area on a Victorian listing before you inspect, using Vicmap and Scout.
8 November 2026Depth x velocity flood hazard in Tasmania: reading the model
How to read modelled depth, velocity and the depth x velocity hazard class in a Tasmanian flood model, and what the numbers mean for a floor level.
5 November 2026NSW site data into Civil 3D and QGIS: a setup checklist
A working checklist for getting NSW contours, LiDAR and cadastre into Civil 3D, QGIS and ArcGIS, with the right MGA2020 zone and lot boundaries from the Portal.
3 November 2026Basaltic clay in Melbourne's west: a desktop worked example
A worked geotechnical desktop example for a basalt-plain block in Melbourne's west: geology, shrink-swell index, likely AS 2870 class and what the field test co
3 November 2026How to open GIS export files: Google Earth, CAD and QGIS
Open a property GIS export with no special software: see the boundary in Google Earth, plus the files for CAD, QGIS and 3D, and what the boundary line is.
3 November 2026Do you need council approval for a granny flat? QLD, NSW, VIC and SA
When a granny flat needs council approval in QLD, NSW, VIC and SA: the no-DA pathways, size limits, overlays that change the answer and the building approval.
1 November 2026Tasmanian Planning Scheme zones explained for buyers
What the zones in the Tasmanian Planning Scheme mean for what you can build, how to find your zone on LISTmap, and which codes to check before you buy.
1 November 2026Which property report do I need before buying a house?
Which property report to get before buying a house in Australia: building and pest, disclosure documents, free planning reports and paid address reports.
1 November 2026Buying a house in Queensland: what to check before you sign
Buying a house in Queensland checklist: Form 2, zoning, flood, bushfire, title, pool safety, body corporate and ground checks, and where to get each.
1 November 2026Buying a house in NSW: what to check before you exchange
A NSW buyer checklist: what the vendor must attach to the contract, the section 10.7 certificate, flood, bushfire, asbestos, inspections and cooling-off.
1 November 2026Buying a house in Victoria: what to check before you sign
Victorian buyer checklist: the section 32 statement, VicPlan, flood and bushfire overlays, Melbourne Water flood certificates, the ground and cooling-off.
29 October 2026Depth of suction change (Hs) in Adelaide: why it is 4 m
Why Adelaide sits in AS 2870 climate zone 5 with Hs of 4 m, how that depth drives characteristic surface movement (ys), and what it means for a desktop read.
27 October 2026Screening a Victorian listing: 7 flood and overlay mistakes
Seven mistakes Victorian buyers make reading flood overlays, zones and bushfire mapping on realestate.com.au listings, and what to check instead.
25 October 2026How to read a NSW flood study for one property: a walkthrough
A step-by-step walkthrough of reading a published NSW council flood study for one property: AEP events, modelled depth, velocity, hazard and flood level.
22 October 2026ACT site data into Civil 3D and QGIS: a worked example
A worked example of pulling Canberra contours, cadastre and the Territory Plan zone into Civil 3D and QGIS for early site set-up in the ACT.
20 October 2026Acid sulfate soil myths: 5 things QLD buyers get wrong
Five common beliefs about acid sulfate soils on coastal Queensland lots, set against what the mapping, geology and published evidence show.
20 October 2026Brisbane City Plan interactive mapping: how to use it
How to use Brisbane City Plan interactive mapping step by step, and what it won't tell you: flood levels for the lot and soil reactivity. Where to get both.
20 October 2026Brisbane FloodWise Property Report: how to read it
Brisbane FloodWise Property Report guide: how to get one from the Flood Awareness Map, read flood types, AEP and floor levels, and what it leaves out.
20 October 2026Gold Coast City Plan interactive mapping: how to use it
Gold Coast City Plan interactive mapping guide: look up a property's zone and overlays, find the council's flood maps, and see what the map leaves out.
20 October 2026Ipswich interactive mapping: City Plan 2025 and flood maps
Ipswich interactive mapping guide: check a property's zone, OV12 flood overlay and past flood maps in the Ipswich City Plan 2025, and what the map leaves out.
20 October 2026Logan interactive mapping: how to use the planning map
How to use Logan council's interactive mapping (ePlan) step by step, and what it won't tell you: soil reactivity on the lot. Where to get it by address.
20 October 2026Moreton Bay planning scheme maps: how to check a property
How to use the Moreton Bay planning scheme maps and property look up, and what they won't tell you: soil reactivity on the lot. Where to get it by address.
20 October 2026Redland City Council interactive mapping: how to use it
Redland City Council interactive mapping guide: use Red-e-Map to check a property's zone, flood, storm tide and coastal overlays, and what it leaves out.
20 October 2026Sunshine Coast interactive mapping: how to check a property
Sunshine Coast interactive mapping guide: find a property in council's MyMaps, read the zone and flood, bushfire and landslide overlays, and see its limits.
13 October 2026Land survey cost in 2026: contour, detail and boundary surveys
Land survey cost in 2026: contour and detail survey $500 to $3,000, boundary survey $700 to $4,000+, what moves a quote and what to use before the survey.
11 October 2026Buying property in SA: a due diligence checklist
A stage-by-stage due diligence checklist for buying property in South Australia: zoning, overlays, flood, bushfire, the Form 1 and site risk.
10 October 2026Case study: sun path and LiDAR data behind a Queenslander renovation
How a sun path and LiDAR terrain for one Brisbane lot sized the window hoods, protected a ridge view, chose the glass and placed 7.5 kW of solar.
8 October 2026Thornthwaite Moisture Index in Victoria: climate zone and Hs
How the Thornthwaite Moisture Index sets the AS 2870 climate zone and depth of design suction change Hs across Victoria, and why ys shifts with it.
6 October 2026Form 2 seller disclosure QLD: what listings leave out
What the QLD Form 2 seller disclosure covers from 1 August 2025, the flood, overlay and hazard gaps it leaves, and how to screen a listing before you ask.
6 October 2026ACTmapi guide: find a block, its zone and overlays in Canberra
Find a block and section in ACTmapi, check its Territory Plan zone and read the 1% AEP flood-depth bands, plus the lot-level flood figures it does not give.
6 October 2026Bushfire attack level (BAL): what each rating means for a build
Bushfire attack level (BAL) explained: the six AS 3959 ratings, who assesses them, what triggers one and what each means for building cost and design.
6 October 2026Bushfire prone area map: where to find it in every state
Where to find the official bushfire prone area map in QLD, NSW, VIC, SA, TAS and the ACT, and what each map and category means for building.
6 October 2026Compaction testing of fill: what it involves and what it costs
Compaction testing of fill under AS 3798: density ratio, Level 1 vs Level 2, why it decides controlled fill under AS 2870, and what drives the cost.
6 October 2026Cone penetration test (CPT): what the readings tell an engineer
What a cone penetration test (CPT or CPTu) measures, how engineers read tip resistance, sleeve friction and pore pressure, where it is used and its limits.
6 October 2026Dynamic cone penetration test: the Scala penetrometer explained
What a dynamic cone penetration test (Scala, AS 1289.6.3.2) is, how it is read, its uses on house sites, its limits and how it differs from a CPT.
6 October 2026Flood risk map: where to find the official one in each state
Where to find the official flood risk map for an address in QLD, NSW, VIC, SA, the ACT and Tasmania, what each shows, and what it leaves out.
6 October 2026Koala habitat map: what QLD and NSW koala mapping means
How to read the koala habitat map in South East Queensland and the NSW koala SEPP, and what mapped koala habitat means for clearing and building.
6 October 2026NSW Planning Portal Spatial Viewer: how to check a property
How to use the NSW Spatial Viewer step by step, and what it won't tell you: modelled flood depth on the lot and soil reactivity. Where to get both by address.
6 October 2026Property boundary map: how to see your boundaries online
See a property boundary map online free in every state, why the line is not a survey, why fences often miss the boundary, and when to call a surveyor.
6 October 2026Queensland Globe: find property boundaries and lot on plan
Queensland Globe (QLD Globe) guide: find property boundaries, lot on plan and a free SmartMap, useful layers for buyers, and what the Globe does not show.
6 October 2026SAPPA guide: look up zones and overlays for an SA property
How to use SAPPA to find an SA property's zone and overlays. It shows a flood overlay but no flood depth, and nothing on reactive clay. How to check the ground.
6 October 2026Sea level rise map: official coastal hazard maps by state
Where to find an official sea level rise map in each Australian state, the allowance each one uses, how to read it and what it cannot tell you.
6 October 2026Sewer easement on your property: what it means before you buy
What a sewer easement on a property means, how to find the sewer, building over or near it in each state, and what buyers should check first.
6 October 2026The LIST Tasmania: how to use LISTmap to check a property
How to use LISTmap to find a Tasmanian property, its title details, planning zone and modelled flood-depth layers, and what a lot-level flood report adds.
6 October 2026VicPlan: how to get a free Planning Property Report
Get the free VicPlan Planning Property Report in a few steps. What it leaves out: how deep a flood gets on the lot and soil reactivity, and where to get both.
6 October 2026What zone is my property? Check zoning and overlays by address in each state
Check a property's zone and its flood, bushfire and heritage overlays free by address in QLD, NSW, VIC, SA, the ACT and Tasmania, and what each means for building.
4 October 2026Reading a Launceston flood model for one property: a worked example
A worked example of reading a published Launceston flood model for one property: AEP events, modelled depth, velocity, hazard and flood level.
1 October 2026SA site data into Civil 3D and QGIS: a setup checklist
A working checklist for pulling South Australian contours, DEM and cadastre into Civil 3D, QGIS and ArcGIS, with the right GDA2020 zone and AHD.
29 September 2026How 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: LIST map, certificate or report
Three ways to check landslip hazard on a Tasmanian block: the LIST map, a council certificate or a property report, and what each hazard band means.
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 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 a house block needs under AS 2870-2011, how deep they go by city, and six common beliefs about borehole numbers 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 2026Site classification myths: six things buyers get wrong
Six common myths about a soil test result, from neighbours' tests to fill, cuts and Class P, checked against what AS 2870-2011 actually says.
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 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 2026Groundwater bore records: where to find and read them
Where to find registered bore logs and groundwater records in QLD, NSW, VIC and SA, how to read a driller's log, and what the records can and cannot show.
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 2026How to open a .12da or .12daz file without 12d Model
A 12daz file is a zipped 12da, a 12d Model text archive. See what is inside and open it free in AutoCAD, BricsCAD or QGIS, or convert it to DXF.
9 July 2026Acid sulfate soils: what they are and what class 1 to 5 means
Acid sulfate (sulphate) soils explained: what they are, where they occur in QLD and NSW, what Class 1 to 5 means 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 in Australia? $700 to $3,000+ for a house
Geotechnical report cost in Australia: soil test from $700, with footing design $1,200 to $2,500, full investigation $3,000+. Desktop report $119.
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: what historical imagery, elevation, geology, land-use history and estate earthworks records show.
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
How reactive soils cause building damage: why clay movement cracks slabs and walls, the usual causes, and what to check before and after.
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, costs and can't do
Geotechnical desktop study (desk study): the ground assessed from existing records, no drilling. What it covers, its cost ($119 to $1,200) and limits.
10 May 2026Geotechnical report vs desktop assessment: the difference
Geotechnical report vs desktop assessment side by side: what each is based on, what it costs, what it can decide, and which one you need.
10 May 2026How much does a soil test cost? 2026 prices by state
How much a soil test costs in 2026: from $700 for a site classification, $1,200 to $2,500 with footing design. QLD, NSW, VIC, SA and WA compared.
10 May 2026AS 2870 site classification explained: what classes A to P mean
What an AS 2870 site classification is, what classes A to P mean, how ys, Iss and Hs set the letter, and why it takes a site investigation to get one.