Where is all London's new housing?

Some of my recent work on housing markets, mortgage lending and housing search has led me to consider the question of where, exactly, London's new housing is located. On a recent visit to King's Cross I was amazed by the sheer scale of development, particularly all the new flats. Because I've been working with the data for another project - and recently re-examined it for a project proposal which explicitly didn't focus on London - I thought it would be interesting to see whether my perception of the flats boom is based in reality. Of course it is! 

The maps below are based on all new build homes sold in London from 1 June 2010 to the end of April 2015 (the most recent data). During this time, according to HM Land Registry 'price paid' data, there were 42,938 transactions on 42,813 properties. This indicates that quite a few properties are not being picked up in this dataset - e.g. compare it to the completions data from the London Datastore. Nevertheless, the patterns and distribution of property types is revealing. 88.8% of transactions were for flats, 7.1% for terraced houses, 2.4% for semi-detached properties and 1.7% for detached houses.

All property types

Flats

Terraced houses

Semi-detached houses

Detached houses

Clearly, the mix of new housing - and its relative low volume - is something that many people have commented on before, but I've not seen many people look at the geographical distribution in this way. The important questions arising from these maps - as ever - is why are things the way they are? That's something the maps can't tell us but it does provide an interesting starting point for debate. The discrepancy between the Land Registry data and data on completions is also not surprising owing to the way new build housing is sometimes sold, but it would be interesting to explore this more in future. If you do happen to have a few million quid to spare, good luck finding a new detached London house to live in!

A note on the maps... I've geocoded the price paid data using Ordnance Survey's Code-Point Open dataset, which can match sales to postcode units, rather than street addresses. The transparent bubble map is of course far from perfect but I've used it here to convey the scale and location of new housing, rather than to offer a precise fix. So long as it gives the impression of there being a massive splodge of newbuild flats in Central London that'll do for now. I am aiming to highlight the general scale and geography of development as a fairly quick experiment to see what might be done with the data. No plans to make it interactive (update: the best laid plans of... see map point datadump below).



Update (1715, 22 June 2015): I fixed the glitches, which were caused by a rogue space here and there in the codepoint open file. Moral of the story? Build more houses (I think). Always a giveaway when there aren't many dots in Wandsworth. The numbers were correct all along though. Finally, I've added in some information from HM Land Registry on properties not included in the price paid data.

Data excluded from Price Paid dataset - link

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.

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 Era of Radical Concrete meets Twitter

Back in 2008, when I moved into my office at the University of Sheffield, there were three mashed up boxes sitting under the desk. My curiosity got the better of me and I spent the next few hours looking through thousands of slides in hanging folders. This turned out to be the image archive of Jimmy James, the first Professor of Planning in our Department and former Chief Planner in England.

In the summer of 2013, after securing funding from the University of Sheffield Alumni Fund, I was able to hire Joe Carr and Philip Brown (recent graduates) to digitise the entire collection and upload it to our dedicated JR James Archive Flickr site. After more than 2 million views and a year online, the BBC magazine did a piece on the archive, called 'The era of radical concrete' which created huge interest and led to a follow up from residents of the places featured in the images. But one image in particular puzzled us... It was simply labelled 'Housing Scotland' (see below for the original slide and the online scanned image)  and we just couldn't fine an exact location for it, but we thought it was in the New Town of Cumbernauld, 15 miles or so from Glasgow.

Note the 'MAY 67' date stamp

Are you the boy? Let us know!

These images were used in teaching planners and urbanists for many years but some of them were not in the right place when we found the slides. We did well to track down the location of most images since between me, Philip and Joe we have a pretty good knowledge of most of the UK and we had thought the one above was of Cumbernauld, because that's where it appeared in the archive.

The New Towns section of the original archive

However, our interest was piqued when a commenter on Flickr said it definitely wasn't Cumbernauld. We tried a few times on Twitter, but to no avail. Even @MunicipalDreams couldn't help us. So, I tried one last time yesterday on Twitter and after 17 retweets we had suggestions that it was definitley NOT South Africa (!), but it might be 'somewhere in Cumbernauld', Falkirk, Dyce, Cwmbran, Killingworth, Peterlee or Saltcoats - among other places. I spent half the night looking round Craigavon, Crawley and Harlow, just to be sure. Nothing.

But this is where Twitter and the power of the crowd came to the fore. Actually, I should say this is when the determination of Michael Coates came to the fore, because ... wait for it ... he found where the photo was taken. It is in fact Abbots View in Haddington, East Lothian - as you can see from the embedded Street View image below. I've shown the 2008 Street View here as it is a better match for location and light but this is definitely it. The perspective of the Google cameras is a little different from Jimmy's original lens but it's a clear match so I declare Michael Coates winner of the Internet today and forever, though the Visual Resources Centre at Manchester Metropolitan University also deserve credit for joining the hunt.

So, that's one mystery solved. But what about the other mystery? Who is the boy on the bike?

By my estimation he'd be about 50 now and if anyone tracks him down we'll really be impressed. In the meantime, if you haven't already looked at the JR James Acrhive, what are you waiting for?