Urban footprints: some building outline data sources

This is an informational post about where to find building outline data, which I've used a lot in previous GIS projects. It might also be of interest to architects, engineers and anyone interested in urban studies and planning more generally. I like using this kind of data to explore cities as it gives us a good idea of the layout of the urban fabric, as in the example below (New Orleans). The links mainly refer to data from the US, Canada and Great Britain but other parts of the world are covered to various extents by OpenStreetMap.

New Orleans

Let's start big, with OSM... Steve Bernard has produced an excellent video which explains how you can get OpenStreetMap data directly into QGIS very simply - he uses Madrid in the example. The accuracy and coverage varies a great deal across the world, so you need to bear this in mind when downloading and using it - but on the whole it is a fantastic resource. The example below shows Mogadishu, where the coverage is incomplete for buildings but pretty good for the road network. 

© OpenStreetMap contributors

Another useful OSM-related resource with decent global city coverage is CAD Mapper, where you can download areas up to 1km square for free. However, I'm focusing on open data today so will not go into detail on this. The best OSM download source is I think GEOFABRIK (German for 'geo factory), a German GIS consultancy who extract and process OSM data and then make it available for free online. It's really nicely structured and easy to find what you're looking for. Here's the download page for New Zealand, for example - followed by the contents, where you can see the building data on top of a current OSM base map. At time of writing, the zipped shp folder for the whole of New Zealand was 146MB.

The New Zealand GEOFABRIK download page (20 July 2015)

Auckland, NZ - very good building coverage here

The OSM sources are great, since the licence is very generous and you can use the data for just about anything, so long as it's properly cited. However, many towns, cities and counties across the world also provide building footprint or outline data (the terminology varies from place to place) so I've put together a list below of ones I know about. Some of them (e.g. Detroit, NYC) cover land parcels or tax lots so are slightly different but in the main it's just building outlines. I've included visuals for some of the datasets, so you can get an idea of what they look like.

New York City - from the BYTES of the BIG APPLE website you can download the MapPLUTO dataset, for all 5 Boroughs in New York City. Tax lot level rather than building outlines, but it's an extremely rich dataset with loads of useful land use planning variables in it, including 'year built' and number of floors. A little sample of the data are shown below, for the area around Central Park.

A little sample of the data (using Qgis2threejs)

Chicago - the building footprints layer is avaiable in two versions online, one of which says it is deprecated but I've heard from the Chicago GIS team that this isn't the case. It's just that due to limited staff the dataset is only edited when necessary. Also contains a 'year built' and height variable.

San Francisco - another really good city buildings dataset, from SF OpenData. Also lots of useful variables in this dataset, including height. I really like this one.

Dallas - you'll probably get a disclaimer box in a pop-up when you go to download this. I've linked to the general GIS page and the file you want is called Structures (Building Footprints) in the Planimetric Data section - it's about 81MB to download and the unzipped file is well over 100MB.

Atlanta - again, I've linked to the GIS page, this time from the City of Atlanta and you need to download the 'Impervious Buildings' layer. If you're looking to map the sprawl of Atlanta, this won't work as it covers the City area only. Still, a very useful dataset.

Denver - excellent open data from Denver. This dataset covers all permanent structures and buildings for a 152 square mile area of the City and County of Denver. Available in a number of different formats.

Seattle - this dataset was created in 2009 by Pictometry International Corp but is now in the public domain. It is available via the City of Seattle's data website.

Los Angeles - this is a fantastic dataset for the County (not just the City) of Los Angeles, which is the most populous county in the United States (just over 10 million). Made available via the LA County GIS Data Portal. It is a little hefty (581MB) so be careful! In the example below I show all the buildings in LA County but the City of Los Angeles in dark shading, just to emphasise its crazy shape.

Boston - this was created in 2012 and is available via the City of Boston. Contains a number of different fields, including base elevation of the structures, the elevation of the highest point above sea level and fields on building type.

Detroit - like New York, not strictly a buildings outline file but instead a property lot level dataset. Very impressive dataset produced by Data Driven Detroit's Motor City Mapping project. I've used this data a lot in talks and teaching as it's a really good example of its type.

Now some links to further datasets which I know of but haven't used that much...

Washington DC - link is to the download page, but direct link to zip is here (559MB unzipped)

Baltimore - the top link on this page

Philadelphia - via OpenDataPhilly

Massachusetts - buildings for a wide range of towns and cities in the state

Boulder - this is from Boulder County, Colorado. Available in a number of different file formats.

Bloomington, Indiana - one of many smaller cities with excellent geodata

New Orleans - an excellent dataset, not just because of the unusual shape of the city!

Toronto - don't be confused by the '3D Massing' terminology here. Scroll down to the 'Data download' section

Vancouver - doesn't cover the whole city and they were digitised in 1999 but still a useful dataset.

Waterloo - this is from the Region of Waterloo and was up to date as of January 2014.

Hobart, Tasmania - an nice example of building data from Hobart in Australia. Contains a 'year constructed' variable.

Wellington, NZ - can't overlook New Zealand! I think you need to register to download this but it's Creative Commons 3 so still open. 

The list wouldn't be complete without mentioning OS OpenData for Great Britain, provided by Ordnance Survey. A new dataset with detailed buildings became available in March (the OS Open Map - Local) dataset. The building data is a very small part of this collection but one I find very interesting. I've patched together a few cities here to get the ball rolling but you can download your own. There's also a 'tile finder' to help you identify which OS tile you need to cover your area of interest. 

This could save you some time 

I think this just about covers it. Get in touch if you have any other great data sources for building outlines.

Visualising Residential Mobility in Urban England

Last year I produced a few commuting maps of England and Wales after the 2011 Census data were released. Now I've turned my attention to mapping patterns of residential mobility in urban areas of England as part of my work on understanding housing markets. This post highlights some of the patterns uncovered in the data - which are output area level migration flows for England and Wales (about 4 million individual flows). If you're interested in how I did this you can find out in a previous post. The first image is of the urban North West of England and for subsequent images I've zoomed to different parts of the country. I've kept it simple and only showed the flow lines, apart from in the North West where I've also added some place labels. It's all a bit experimental at this stage.

You can find a higher resolution image here

The North East of England

West, East and South Yorkshire

I think some places are missing (working on it)

I've adjusted the brightness a little to make this clearer

What does all this show? It shows what many people may already know or expect but basically it illustrates the extent of residential mobility patterns in some of England's major urban areas - plus a bit more in the South West example above. There's a lot more that could be said about this but for now I'll leave it at that. I'm sorry if your town or city isn't on the map! Maybe next time...

Notes: I've filtered the data so in certain cases some places are not shown (e.g. in the North West image places in North Wales are not visible). Also, I've only shown flows of a certain volume in order to filter out the noise. 

WIMD 2014 Shapefiles and Maps

The Welsh Index of Multiple Deprivation 2014 was published on 26 November, using more up to date and improved indicators. The Welsh Government have provided some nice interactive mapping, but James Trimble's version is I think even better. I've done basic interactive versions in the past, but today I just want to share the raw GIS data and a few maps, for anyone who is interested in either looking more closely at their area or doing a bit of spatial analysis themselves. First of all, here are a few basic WIMD maps, clipped to building outlines (click images to enlarge).

I made these in QGIS, using an automated atlas production technique I've described on the blog before. If you are looking to produce some WIMD maps, you might want to try this method. I've also produced some WIMD 2014 maps in standard choropleth format, as you can see below. These are okay in areas which are densely populated but I find them more misleading for larger rural areas where there are not many people.

I know a lot of people across the public sector in particular will be looking closely at the data, so I thought it would be helpful to make the underlying shapefiles publicly available since the data are open. If you click on the link below you'll be taken to a download page via Google Drive. Any questions, then feel free to get in touch.

Download files: WIMD 2014 Shapefiles - for LSOAs and LSOAs clipped to building outlines.

Mapping Methods

I've done a lot of mapping on this blog in recent months. Much of this has been about deprivation and my attempts to make more widely available maps on deprivation for different parts of the UK. For this, I've often used Google's Fusion Tables. The most recent work I've done with this data using Fusion Tables is to update the Welsh Deprivation work to include the most recent release of the Welsh Index of Multiple Deprivation from 2011. There's a screenshot below which links to a full page Google map. If you click on an area the pop-up will tell you all about it in relation to the WIMD data. This post isn't about the data but the most deprived area is in West Rhyl and the least deprived in Cardiff (Llandaff area).

But this post is about methods, so more on that before I go... The steps below relate to any kind of data I've mapped using Fusion Tables (warning: technical content!).

1. First of all I usually have to join attribute data to spatial data. I do this in ArcGIS but it works well in MapInfo too. If you're a MapInfo user and want to follow the steps below, use Universal Translator in MapInfo to convert the file to a Shapefile first.

2. I don't like overly detailed boundaries because of the large file sizes and often this exceeds the Fusion Tables file limit. So, I simplify the boundaries. For this, I use mapshaper, a great online tool. You can also use other GIS methods.

3. Then I use something called shpescape. This is a really great tool because it allows you just to zip your shapefile (i.e. the shp, shx, dbf and prj files) and then upload directly to Fusion Tables without having to convert to KML as an intermediate step.

4. Once there, all you need to do is go to Visualize / Map and then go to work customising things. This includes map colours and what appears in the Info Window pop up when you click an area. I've blogged on the Info Window code bit before.

5. If you want others to see it you must make it public. Just click 'Share' in the top right of the Fusion Table screen.

That's about it. The Info Window code bit takes a while to figure out but you can do so much with it.

Deprivation in Wales

My experiments in mapping deprivation continue... I should really have done something on Wales before now but to make up for it I've done a 3D annotated map, a Google fusion table version with Welsh Index of Multiple Deprivation 2005 and 2008 data (also embedded below), plus a new version of a fusion table map with a drop-down menu for choosing local authority areas. For both the google map versions you can find out about each area just by clicking on it.

Click here for a full size version, and here's the shortened URL http://goo.gl/GYnIF

Finally, here's a screenshot of the page with the drop-down menu for selecting local authorities. You can click here, or click on the image below to go to the separate web page for this one...