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.

Creating an English green belt atlas

UPDATE: I've fixed the glitches in version 1 and compiled a spreadsheet with the data. See new download at the bottom of the post.

I've blogged before about green belt, and also written about the underlying data in the press. Now that the data are open, I've finally got round to finishing a little project I meant to complete ages ago. I was prompted to do this during a recent visit to my department by Prof Bob Barr, a legend in the data and GIS worlds. Bob said it would be good to know what percentage of the land area in each local authority in England was covered by green belt. I agree, so here are the results of my analysis (using 2014 green belt data) from Version 1 of my English green belt 'atlas' (actually lots of individual images to keep the file size down). Here's a snapshot of one of the maps...

Green belt land in Cheshire East

And another, this time from Birmingham. You can see that I've dimmed the background so that you can get a sense of other green belt land in the areas I've mapped.

Birmingham green belt land

Finally, a few more from around the country...

There are some glitches in the data but my initial overview suggests the numbers are pretty accurate (see exceptions below). I hope that people might find these maps useful. If you want to use any of them, be my guest.

Download all the files here (154MB): Green Belt Atlas 2014 (version 2) (186 individual map files, plus spreadsheet)

Download just the spreadsheet: percent green belt figures for each of the 186 local authorities:

Contents of the spreadsheet (download above)

Warnings: A couple of issues with version 1... 1. The West Lancashire greenbelt area extends into the sea on the green belt shapefile available from DCLG, so the figures here are incorrect (working on a fix). 2. The figure for Ashfield is clearly wrong - not sure why, so I will fix that too. 3. Some areas have extremely low values and may not actually be in the green belt - it may instead be down to the accuracy of underlying data. 4. Mole Valley currently missing, am looking into why. UPDATE: I looked again at the original Green Belt shapefile from DCLG and found that Mole Valley had the same code as Ashfield, so I fixed that and there's now a map for Mole Valley. New Forest was also assigned two different codes, so I've fixed that too. Also, in the percent figure, I've exluded the part of the West Lancashire green belt that is not on land, so this gives an accurate figure now. You can see from the image below that part of the green belt goes into the Ribble Estuary.

Technical stuff: I did this in QGIS 2.8 (open source GIS software) using the Atlas tool and a very heavy laptop, plus a bit of trickery I picked up here and there. I blogged about this before, with a little tutorial. Perhaps I should actually be using the term 'green belts', as Richard Blyth pointed out, but forgive me for this.

The Polycentric South East

Tweets yesterday from Michael Edwards and Joseph Kilroy reminded me of a map I produced last year in which I showed commuting patterns in South East England, minus London. I did this to get a sense of the polycentric nature of travel to work in the South East as this has been a topic of many previous studies - including the famous Hall and Pain book - but none (to my knowledge) using the 2011 Census data I mapped. The other reason for me blogging about this today is that I'm speaking on a similar topic at Modelling World 2015 this Thursday in London. Enough words, time for some maps, which I've refreshed for this week.

The first map below shows all commuting in the South East of England in 2011, without place names. As you can see, I've removed London from the equation, both in relation to travel to work flows and from the underlying map canvas. This gives a slightly different perspective than the one we're used to. The second map is the same as the first but I've added the names of local authorities in order to help identify places. Click any of the images to enlarge.

Commuting in South East England, 2011

Same as above, but with labels

Now, here's what it looks like when you add London back in... Kind of brings to mind astronomical metaphors, as hinted at in a previous study by the RTPI. I should add that the definition of a supernova is 'a star that suddenly increases greatly in brightness because of a catastrophic explosion that ejects most of its mass' so this might be stretching things slightly... Then again, if what people are saying about the displacement of the poor from London this might actually be spot on.

The 'London Supernova'

Finally, I've produced a zoomed-in version closer to London where you can see some of the flows which go through/over the capital. I don't fancy that commute!

Static maps from CartoDB

I've used CartoDB quite a bit recently to create interactive maps. My Historic Buildings of Scotland map and my England Grade I Listed Buildings map have both proved popular. Another map that received lots of traffic was my English Greenbelt map. This one in particular was popular I think because it allowed people to find out exactly where the green belt was near them - or in fact to find out which areas aren't greenbelt. Although interactive maps are great for some things, sometimes we just want to put a static image in a report or on a website and this can often be a bit tricky with interactive content. Luckily, CartoDB allows users to export static image files (png format), and you can customise the dimensions as well. This CartoDB blog post shows you how - though you may need to disable pop-ups in your browser if it doesn't work. This tool opens up the static map in a new browser tab so if nothing happens check your pop-up blocker settings.

View the full size version

As you can see above, I've exported my English Greenbelt map. I often get asked if I have a large static image of it because if you search online there aren't really any large up to date, decent resolution, detailed green belt images. I also added some attribution information (important!) and a basic title. This is just a quick example so isn't perfect in relation to labels and so on but it gives a simple overview of the green belt.

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. 

The Urban Fabric of English Cities

[now updated, thanks to @udlondon - scroll to bottom of page]
Inspired by some mapping in the US by Seth Kadish, the availability of new GIS open data, and the fact that I love looking at patterns of urban form, structure and density, I have created a comparative graphic showing the building footprints of nine English cities, with London at the centre (just because it's biggest). I have done this in a very simple way, with all cities mapped at a scale of 1:125,000 in the full size versions (which are massive), plus one small scale bar and a little explanatory text. Here's what it looks like:

The urban fabric of English cities (black/red, medium res)

This graphic does a good job - in my view - of demonstrating the compactness or otherwise of the cities in question. It also illustrates how tightly-bounded some places are and how under-bounded others are. For example, Liverpool is very dense and compact in contrast to Leeds but this really is a boundary effect because the size of the local authorities differs so much. The urban area of 'Liverpool' extends far beyond the boundaries of the local authority area, which is what I show above. I wanted to compare the local authority areas rather than the wider city-region because I wanted to highlight this boundedness issue and compare like with like in terms of formal administrative areas. London is obviously a bit different so I've shown the 33 constituent parts of Greater London.

Take a closer look at the graphic by clicking on the two larger images below - one in white and one in black. They are both just a bit bigger than A0 paper size in their full size versions in the zipped folder below so if you want to take a really close look, download them. I've also uploaded smaller-sized versions in the same folder. I deliberately didn't include more information on the graphic itself, but at the bottom of the post you'll see the population of each city in 2011 (which relates to the individual city images), plus its urban area and metropolitan area population. The population of Greater London in 2011 was 8.2 million (compared to 4.4 million for the other cities shown). The cities I selected are the English members of the Core Cities group, which now also includes Glasgow and Cardiff.

Click here for a full screen white version

Click here for a full screen black version

Download a zipped folder with black and white versions in different sizes.

Update: the @udlondon people got in touch via twitter to show their attempt at fitting the core cities inside the London boundary - as below - so this inspired me to try the same with the original data. The first image below is the original @udlondon artwork and the next one is my attempt using GIS. Finally, as a reminder that nothing is ever really new, I have added a similar map which we found as part of the JR James urban image archive which we launched last year. This version has 13 different cities.

A manual approach to GIS!

My attempt at the same thing, using QGIS - full size

Some of the boundaries were a bit different in those days

City	Population	Urban area	Metropolitan area
Birmingham	1,085,400	2,440,986	3,683,000
Bristol	428,200	587,400	1,041,000
Leeds	751,500	1,499,465	2,302,000
Liverpool	466,400	816,216	2,241,000
Manchester	503,100	2,240,230	2,556,000
Newcastle	280,200	879,996	1,599,000
Nottingham	305,700	666,358	1,543,000
Sheffield	552,700	640,720	1,569,000

Totals: the population of the 8 city local authority areas is 4.4 million, for their urban areas it is 9.8 million and for their metropolitan areas it is 16.5 million. I may compare metropolitan areas next time, but mapping this is a little more time consuming.

Deprivation in your area - search and zoom

After making a new website when the Scottish Index of Multiple Deprivation 2012 was released, I've been looking at some of my old English IMD web pages and tools and so have decided - in anticipation of the next update to the IMD - to add a 'search and zoom' tool so that anyone who is interested can find out what deprivation is like in their area - or any other area of England you are interested in. Like my previous versions of this kind of thing it's based on Google Maps but in the version seen in the screenshot below you can simply enter a place, neighbourhood, postcode or address (or even an organisation, like Centre for Cities) into the search box and it will go straight there after clicking 'search'. Click the image or the link below to use the tool.

IMD Search and Zoom

As usual with these kinds of maps, if you click on an area the pop-up will give you more information. The next update of the IMD was to have been in 2013 but I'm not sure if that is still going to happen. However, I've updated this tool just in case so that I can add in the next update whenever it becomes available. The Scottish version of this tool is on this page, but I have not yet done the same for Wales or Northern Ireland.

Premier League Poverty?

The financial health of the English Premier League is a regular topic of discussion. No matter how you look at it, the sums of money involved in the operation of Premier League teams are immense and it looks even more striking when you consider the locations of their stadia - typically in the most deprived areas of England. This is related to a number of factors (e.g. history, land values), but in my work on neighbourhood deprivation and mapping I've noticed a common trend over the years so I decided to look at the location of all 20 current Premier League teams in England and how deprived their local area is, using the Government's official measure of deprivation (the IMD*). The maps below show each team and its area's deprivation rank within England, where 1 = most deprived and 32,482 = least deprived. Shading: red = poorest 20% of areas in England, yellow = next poorest 20%, and so on... Liverpool is most deprived and Fulham least. See below for more.

Arsenal - IMD 4,432 

Aston Villa - IMD 479

Chelsea - IMD 5,483

Everton - 1,070

Fulham - IMD 19,076

Liverpool - IMD 219

Manchester City - IMD 599

Manchester United - IMD 10,235

Newcastle United - 18,570/6,582 (split)

Norwich - IMD 12,253

Reading - IMD 6,843

Southampton - IMD 855

Spurs - IMD 950

Stoke - IMD 2,171

Sunderland - IMD 6,291

Swansea - WIMD 374

West Brom - IMD 1,619

West Ham - IMD 3,593

Wigan - IMD 429

QPR - IMD 7,848

In Newcastle, the stadium is split between two areas, so I have given the deprivation ranks for both areas. The English Indices of Deprivation obviously only cover England so I have included a map for Swansea which uses the Welsh Index of Multiple Deprivation figure from 2011. More on that in a previous post. Similar patterns exist in Scotland, as you can see from the bottom part of this 2009 post. What does this tell us that we didn't already know? Not much, but it does provide some hard data and an overview of the contrast between the wealth of clubs and the poverty of many local areas they are located in.

* The English Indices of Deprivation 2010 are used here. They rank each of the 32,482 Lower Layer Super Output Areas of England from most deprived (a rank of 1) to least deprived (a rank of 32,482), taking into account such things as income, employment, education and health. There was a similar piece of analysis in Regeneration and Renewal in 2009 but this looked at the local authority areas only and not the specific location of stadia.