Buildings

Disclaimer

Geoscape Australia believes this publication to be correct at the time of printing and does not accept responsibility for any consequences arising from the use of the information herein. Readers should rely on their own skill and judgement to apply information to particular issues.

This work is copyright. Apart from any use as permitted under the Copyright Act 1968, no part may be reproduced by any process without prior written permission of Geoscape Australia.

Overview

Buildings is a digital dataset representing buildings across Australia. The Buildings dataset has relationships with the G-NAF, Cadastre, Property and Administrative Boundaries products produced by Geoscape Australia.

Data quality and potential capture timelines will vary across Australia based on three categories. Each category has been developed based on several factors defined by the population distribution (categorised based on population size), industrial/commercial activities, the probability of natural events (e.g. flooding) and the image source.

• Urban (satellite source) - areas with a population greater than 200, or with significant industrial/commercial activity in a visual assessment, digitised from satellite imagery

• Urban (aerial source) - areas with a population greater than 200, or with significant industrial/commercial activity in a visual assessment, digitised from aerial imagery

• Rural – all other areas

Geoscape welcomes your feedback on the Buildings product. We also publish regular product development updates on our website ( www.geoscape.com.au ).

Release Summary

This product was released to customers on 27 June 2024 with data extracted on 20 June 2024.

• This release is a full national data population for Version 3.2 of the Buildings product, described by the Buildings Product Guide v3.2.

Any issues that have been identified for this release are described in the Issues section.

This release includes updates for the areas listed in the table below.

Locations of updated areas by State

State	Location	Urban Area (km2)
QLD	Brisbane City	360
QLD	Cairns Regional	151
QLD	Ipswich City	268
QLD	Logan City	81
QLD	Mackay Regional	82
QLD	Moreton Bay City	232
QLD	Redland City	65
QLD	Townsville City	197
SA	Adelaide Hills Council	4
SA	Adelaide Plains Council	50
SA	Alexandrina Council	24
SA	Campbelltown City Council	29
SA	City of Adelaide	15
SA	City of Burnside	25
SA	City of Charles Sturt	61
SA	City of Holdfast Bay	14
SA	City of Marion	56
SA	City of Mitcham	55
SA	City of Onkaparinga	198
SA	City of Playford	101
SA	City of Port Adelaide Enfield	104
SA	City of Prospect	9
SA	City of Salisbury	103
SA	City of Tea Tree Gully	66
SA	City of Unley	14
SA	City of Victor Harbor	24
SA	City of West Torrens	37
SA	Light Regional Council	22
SA	Mount Barker District Council	39
SA	The Barossa Council	5
SA	The City of Norwood Payneham and St Peters	15
SA	The Corporation of the Town of Walkerville	4
SA	Town of Gawler	40
VIC	Ballarat City	154
VIC	Glenelg Shire	79
WA	City of Busselton	98
Total		2881

[1]

Location names are derived from an intersection with the most recent Local Government Area dataset, Geoscape, 2023.

Spatial files of the updated areas are available upon request via support@geoscape.com.au.

Change Notifications

Inclusion of addresses from all G-NAF suppliers within the building_address table

Currently, the Buildings product is associated with a subset of addresses from the Geocoded National Address File (G-NAF). The linked addresses only relate to a select group of G-NAF data suppliers.

Commencing with the September 2024 release, we intend to extend this association to all address suppliers used in G-NAF. The significant benefit of this enhancement will be the improved alignment of linked address data with the G-NAF dataset. This will result in improved relationships, notably the inclusion of more secondary addresses. The address relationships in the ‘building_address’ table will increase by over 7.5 million records (~20%).

In the June 2024 release, we are demonstrating the increased association by providing a supplemental table alongside the Buildings product named ‘building_address_additional’ containing the additional address relationships. The standard ‘building_address’ table in the June 2024 release will not incorporate the additional addresses.

The ‘building_address_additional’ table will be provided in PSV format and can be downloaded from Geoscape Hub under Data > Custom Download. The date_created and date_modified attributes are currently set as NULL but will be populated when these records are incorporated into the standard product.

The additional table will not be provided in the following, September 2024 release, as the additional records will be incorporated into the standard ‘building_address’ table.

ACT, Queanbeyan-Palerang and Yass Valley Regions

A Review of the Buildings capture data during processing has identified that the supply for the below areas was not suitable for the product refresh. Therefore, this led to the removal of the following areas mentioned in the pre-release report.

• ACT

• Quenbeyan-Palerang Regional Council

• Yass Valley Council

These Regions will not be updated in the June Release and will be rescheduled to be updated in a future release.

Removal of the ‘Documents’ folder from data packages

Geoscape has moved product descriptions, guides and reports online to https://docs.geoscape.com.au From this release onwards, data packages will no longer include the ‘Documents’ folder.

Issues

New Issues

No new issues to note.

Resolved Issues

No new resolved issues.

Known Issues

roof_material classification

Over classification of buildings with a primary roof material of ‘Tile’. Geoscape Australia continues to work with its partners to improve the techniques used in the classification of roof materials. For further information please refer to Classification Correctness - Building Roof/Roof Material in the product description.

Centroid not within building polygon

When mapping the building centroid from the centroid_longitude and centroid_latitude there will be occurrences where the point does not fall inside the building geometry. This occurs because of the complexity of the building geometry and impacts < 0.1% of buildings. A fix for this issue will be investigated for a future release.

Swimming_pool_adjacent incorrectly ‘null’

Some records containing attribution for swimming_pool_review_date also contain ‘null’ attribution for swimming pool adjacent where the allowed values are ‘no’ or ‘yes’. This affects < 0.25% of buildings.

Duplication of buildings between update areas

New and updated buildings are captured within Areas of Interest (AOIs). Buildings that intersect two adjacent AOIs are duplicated. This issue affects approximately 1,800 buildings.

Duplicate building polygons

There are 8,417 buildings with duplicate geometries, resulting in 8,427 additional building polygons present. A fix for this issue will be investigated for a future release.

Roof colour assignment

There is an over classification of light roof colours primarily in the Melbourne region. Advances in processing has improved this issue in recent releases.

Building position offset from imagery

There is evidence of buildings having a horizontal shift of approximately 0.5m in the NSW suburbs of Parramatta and the Dee Why area. This has occurred where the new shift to the digital elevation model has not worked as intended. As we continue to refine the aerial derived building processes, we’ll seek to resolve this issue.

Over-capture of metal roof material in aerial supplies

In the June 2022 release, we have noticed that there is an over-capture of Metal roof type in the aerial capture. This occurred primarily for residential buildings. In some areas of the new aerial capture (e.g. Perth and Cairns), Metal classification was actually improved overall in relation to the previous satellite capture (satellite previously incorrectly classified Metal roofs as Tile). We are working with our production partners to improve the accuracy of the roof_material attribute, which can be affected by image smoothing, causing Tile roofs to be incorrectly classified as Metal.

Future Considerations

This section outlines enhancements or changes under consideration, but not planned into a specific release. For further details on future initiatives, please contact Geoscape Support.

Legacy ‘CAD’ naming

The building_cad table contains a field that is called ‘cad_pid’, while the Cadastre product has an attribute called ‘cadastre_pid’. We have input the ‘cadastre_pid’ values into this ‘cad_pid’ field to not affect customer processes with attribute name changes. In addition the table name of ‘building_cad’ no longer matches the Cadastre product. There is no current plan to change either the ‘building_cad’ table name or ‘cad_pid’ field name.

Additional Total Floor Area attribute

Geoscape intends to introduce a new total_floor_area attribute to a future release of the Geoscape Buildings product. This attribute will provide the estimated sum of floor space across all levels of a building. At the time of the addition of this new attribute there will be a minor increment to the Geoscape Buildings product version.

Annex A – Release Counts

For the buildings table the additional, retired, updated and total building counts, as well as the percent change to the previous release have been listed in the table below. For the aspatial tables the total record counts have been listed.

TABLE			ACT	NSW	NT	OT	QLD	SA	TAS	VIC	WA	TOTAL
buildings	Additional		0	0	0	0	86,745	250,798	0	26,123	3,634	367,300
	Retired		0	0	0	0	54,160	182,890	0	13,906	1,019	251,975
	Updated		280	14,292	69	0	706,178	791,274	1,243	115,242	35,058	1,663,636
	Total		242,136	5,216,664	160,205	449	3,767,539	1,779,239	594,333	4,959,217	2,265,141	18,984,923
	% Change		0.00%	0.00%	0.00%	0.00%	0.87%	3.97%	0.00%	0.25%	0.12%	0.61%
	Solar Panel	Yes	37,964	593,590	15,835	8	674,852	294,379	32,227	550,007	387,921	2,586,783
		No	202,607	3,684,153	111,233	329	2,483,582	1,129,062	403,908	3,598,062	1,459,231	13,072,167
	Swimming Pool Adjacent	Yes	17,881	667,490	38,977	0	747,848	128,913	9,062	297,709	349,791	2,257,671
		No	222,792	3,623,003	87,562	355	2,419,831	1,293,148	430,050	3,865,960	1,501,789	13,444,490
building_cad			287,814	11,817,636	323,504	554	5,644,546	2,277,001	720,009	9,523,567	4,507,430	35,102,061
building_property			251,067	6,232,117	262,741	0	5,635,089	2,198,563	625,786	11,686,256	2,281,004	29,172,623
building_address			696,156	10,018,155	239,599	75	5,730,651	2,219,297	668,382	7,888,938	3,595,804	31,057,057

References

[Aerometrex, 2023]

Aerometrex. Aerial imagery. Raster Dataset, 2023. URL: https://aerometrex.com.au/.

[Geoscape, 2023]

Geoscape. Local government areas 2.0. 2023. URL: https://docs.geoscape.com.au/projects/lga_guide/en/stable/index.html.