Eoin O’Mahony, UCD and TCD.

I have been working for a while now with the data produced by the InsideAirBnB project. I teach students how to map and analyse these kinds of datasets when they are learning to use geographic information software. The data are really useful to understand how the city changes, how urban unevenness plays out and what can be done to undermine the ‘sharing economy’. That last phrase in particular, the sharing economy, is very pernicious. Sharing usually involves me giving you something and, maybe, you giving me something. In the case of AirBnB, money is given over for a space to sleep and eat.  That doesn’t sound like sharing to me but old fashioned marketised social relations. The same goes for the gig economy: the last time I went to a gig, I wasn’t asked up on stage to pound out a few tunes with The Unthanks.

This morning, I read that Dublin City Council have finally published their report on the impact that AirBnB is having on Dublin City’s housing. One of the more significant reported findings is that there are many individual people renting out multiple short lets. Downey’s report for the Council (which I have yet to read) recommends that two Council committees work together to figure out a way to “tackle the issue”. While we await the Council’s prognostications, let’s examine some of the impacts that the most recent batch of data (February 2017) points to. This is a kind of geography of AirBnB in Dublin, a way in which to help analyse the current housing crisis. This is the housing crisis that Coveney would like to solve part of before June, you know, after winning the leadership race of his party. Priorities, right?

Firstly, within the City Council area, there has been an increase in the number of listings between August last year and the February scrape. In August, there were 4,931 listings for the city area – the vast bulk of all Dublin region listings. By February, this had increased to 6,729, an increase of 36%. There must be few other things in the city that have increased by this amount in this period, except perhaps seagull droppings.  There has not been a 36% increase in the output of social and affordable homes in the city over this period. There is clearly a number of people out there who have apartments in the city who know that if they rent the spare room or the whole apartment they can make some money. Short-term lettings like these allow people the flexibility to rent some weekends and not others but also to pay a mortgage on a second (or fifth or eighth) rental property they just happen to have lying around. It beats having long term tenants it would seem. Perhaps significantly, the proportion of listings that rents the whole property out (as opposed to a room) has remained stable at 47% of all listings.  So where are these listings located?

One of the really good features of a geographic information system (software that allows for spatial analysis) is to be able to see patterns across the city. I conducted a point-in-polygon analysis of the data from the February 2017 listings dataset. As the name implies, this counts the number of listings within each predefined area, in this case electoral divisions (EDs). There are 162 EDs in the DCC area. Location information for these listings are anonymized by Airbnb so any scraping process encounters the following spatial constraints:

    • the location for a listing on the map, or in the data will be up to 150 metres from the actual address.
    • listings in the same building are anonymized by Airbnb individually, and therefore appear “scattered” in the area surrounding the actual address.

I would be interested to see how Downey may have compensated for this in his report for the Council. Any point-in-polygon analysis is therefore compromised by these two constraints. Knowing this, what spatial patterns can we see? The average number of listings per ED is about 34. In the first map below we can see the distribution of listings below, around (±10), and above the average.

Edit: dynamic map is now available here.

number of listings per ED


The parts of the city that have above average listings include the docklands, the north inner city around Mountjoy Square and near Stoneybatter. By the far the largest concentrations of listings are seen south of the river, particularly in the south docklands and around Temple Bar. Focusing on those EDs with 100 or more listings, it is clear that the areas south of the river have many more listings than those north of it. This may point to a greater availability in these areas.

EDs with 100 or more


Interestingly, the gap between in the southside of the map above contains the areas fancifully known as ‘the Georgian core’. The sabre-shaped ED known as South Dock has well over 300 listings. This takes in an area including the south docklands as well as the area immediately to the south and east of Trinity College. In and around the City Council building on Wood Quay is an area of high concentrations. Thanks to a suggestion by Martin at NCG, I then normalised these listings data by the number of housing units per ED from the 2011 Census. This gave a slightly different geography to the listings data. The average per area is a little under 2% of all housing units. Again, I classified the normalised listings data by below, around and above average but have not displayed the below average areas. We can note a number of differences, as is clear from the final map below.

as a percentage of


13% of the units in south inner city are listed as AirBnB-available units. About 9% of the units South Dock are. The Georgian core comes back into play. The heaviest concentrations of listings are therefore found in the south inner city, heading west. I would like to read Downey’s report on this before I do any more work on these data. What’s not clear to me of course is if the Council is going to take any concrete actions to at least curb the power of property to yield profits in the middle of the city’s worst housing crisis.  As Lorcan Sirr has indicated recently, some in control of this city have a strange relationship of denial with data. Action would require the Councillors to push back against the primacy of private property so you know…..not much will happen unless we organise like they’ve done in Barcelona and elsewhere.

Much of the coverage concerning the preliminary Census release from yesterday has focused on vacancy. This has meant distinguishing between those housing units classed as holidays homes in each area and units that are ordinarily vacant. One of the more puzzling statistics to emerge from this distinction is the 190% increase in the number of holiday homes in Dublin city since 2011. In that year, there were 322 vacant holiday houses in the city but those rose dramatically to 937 in April’s census.

What might account for this near trebling in five years? In particular why, in the middle of a housing shortage, is there almost twice as many housing units classed as holiday homes in a dense urban area when compared with five years previously? Speculation with some others on twitter concentrated on the possibility of these being AirBnB properties. I decided to put some focus on this explanation to see if there’s any truth to it.

In recent months there has been a number of online features concerned with how AirBnB (a company which matches bodies with beds across the world) might be affecting rents. If people are renting their city property through AirBnB for much of the year, how might this affect people seeking to live and work in the city full time? For example, in a number of North American cities there are concerns that full-time AirBnB rentals are displacing residents (e.g. see here or here) who are in lower paid jobs and subject to ever-increasing rents. Some city authorities are coming under pressure to restrict the use of full-time rentals through the company. A property owner can make far more renting out short term lets to passers-by than s/he can from locals who are seeking merely to continue living in a city they work and have a life in.

There is a vital politics to this displacement where AirBnB rentals are pricing people of lesser means out of particular areas of a city bustling with tourists. It is an extreme example of gentrification by displacement, almost making the popular term redundant in its bluntness. The uneven geographies of AirBnB rentals hits home for many in this city too.

In Dublin in June, the city council raised the prospect that full-time AirBnB rentals in Temple Bar, a particular zone of intense tourist activity, would be subject to planning permission. The Council argued that a particular property in the neighbourhood was effectively a material change of use from residential to commercial. It insisted of course that this ruling was “site specific” and did not cover the entire Temple Bar area. The prospect of an imposition of a change of use for the area as a whole is remote though: this seemed like a shot across the bow.

Luckily for us, InsideAirBnB allows us all access to data for rentals across a large number of cities to determine if the company is facilitating displacement. I took the January 2016 data from this site and, aside from knowing the first names of each of the renters, the database contains a number of interesting data.

There are 3,772 properties in the AirBnB database in the four local authority areas. Of this number, 3,116 (83%) are in the Dublin City Council area. 1,222 or 39% of this subtotal are for rent, according to the dataset available under Creative Commons, for 300 days or more per year. The heatmap below (Map 1) shows that near-year long rentals are broadly clustered within the Temple Bar, Cow’s Lane and north Docklands areas. Those rented 365 days per year (249 properties) are distributed slightly differently. They are by no means overlooking the splendour of Dublin Bay.

Map 1: a heatmap of the 1,222 properties available for 300 days or more on AirBnB. Data: InsideAirBnB and OSM contributors.

Map 1: a heatmap of the 1,222 properties available for 300 days or more on AirBnB. Data: InsideAirBnB and OSM contributors.

They are scattered across the city with some clusters in Drumcondra, Rathmines and Portobello. Map 2 below shows the distribution of these year-long AirBnB properties across the Dublin City area, Map 3 shows the distribution of entire house/apt available for rent for 300 plus days a year (as opposed to a room in an already occupied dwelling).  It is not beyond the realm of possibility therefore that the >300 days per annum rentals in this database includes a figure of 937 holiday houses recorded in the census. In fact, there are 934 properties rented out for 335 days or more per annum in the database. If you spent the month of December in your own city centre apartment, and rented it out for the remaining 335 days of the year, you might well be among the 937 recorded in the Census.

Map 2: Year-long AirBnB rental properties (n=249) in the Dublin city area. Data: InsideAirBnB and OSM contributors.

Map 2: Year-long AirBnB rental properties (n=249) in the Dublin city area. Data: InsideAirBnB and OSM contributors.


Map 3: 300 plus days per year of entire housing unit /apartment for rent on Airbnb. Data: InsideAirBnB and OSM contributors

But this is a numbers game. We’ll have a better sense of the distribution of the city’s holidays homes when the more extensive data release begins in April 2017.

Eoin O’Mahoney


For the past couple of years the housing discourse for Dublin city has been one of housing shortages and a homeless crisis. The preliminary census figures published yesterday reveal that while the vacancy rates (exc holiday homes) for South Dublin (4%), Dún Laoghaire-Rathdown (5.7%) and Fingal (5.3%) are below a base vacancy level of 6% (in a ‘normal’ market we would expect c.6% of stock to be vacant due to selling/rental gaps, deaths, etc), suggesting that they have housing undersupply, Dublin City Council has a vacancy rate of 8.6% (exc. holiday homes).

In total DCC has 21,781 vacant units (20,844 exc holiday homes).  On a base vacancy of 6% (14,544 units) that suggests an oversupply of 6,300.

In other words, there is something pretty odd going on given the homeless rate has been increasing, large numbers are on the housing waiting list, and there’s a widespread belief that the city desperately needs to build housing.

So, what constitutes these 6,300 excess vacant units?

It’s somewhat difficult to know without visiting them and doing an on-the-ground survey, but let’s start with looking at the geography of vacancy in DCC.  Map 1 shows the % vacancy in the city minus holiday homes, and Map 2 shows change in the number of vacant units since 2011.

Map 1: DCC vacancy rates (exc holiday homes)

Map 1: DCC vacancy rates (exc holiday homes)


Map 2: DCC vacancy change 2011-16

Map 2: DCC vacancy change 2011-16

In Map 1, all the areas not shaded pale yellow has a vacancy rate (exc. holiday homes) above 6% base vacancy.  Much of the city centre and to the south have rates above 10%, and two EDs have rates above 20% (Mansion House B, Pembroke West B).  In Map 2, the blue areas have seen vacancy rates decline between 2011 and 2016, whereas red areas have seen an increase.  Interestingly, a number of areas have seen quite large increases in vacancy, especially within the canals near to the city centre, Ballsbridge and Rathmines.

Here’s some speculation as to what constitutes the excess vacancy:

  • some unreported airbnb/similar stock;
  • some second homes (used during week, but primary residence recorded as somewhere else);
  • some investment stock left empty;
  • some bedsits not yet converted after change in regulations that made them illegal;
  • some inner city obsolescence.

I’d be interested to hear about other possibilities.

Whatever the reason for the vacancy, it appears that this stock is not presently available to the market and therefore there continues to be a shortage of housing in the capital.

Rob Kitchin