Open data for a better understanding of the housing situation in Spain

Housing is one of the main concerns of Spanish citizens, according to the January 2025 barometer of the Centro de Investigaciones Sociológicas (CIS). In order to know the real situation of access to housing, it is necessary to have public, updated and quality data, which allows all the actors in this ecosystem to carry out analyses and make informed decisions.

In this article we will review some examples of available open data, as well as tools and solutions that have been created based on them to bring this information closer to citizens.

Examples of housing data Open data can have several uses in this sector:

• Enable public bodies to understand citizens' needs and develop policies accordingly.
• Helping individuals to find homes to rent or buy.
• Providing information to builders and companies so that they can develop housing that responds to these needs.

Therefore, in this field, the most used data include those referring to housing, but also to demographic and social aspects, often with a high geospatial component. Some of the most popular datasets in this sense are the Housing and Consumer Price Indexes of the National Statistics Institute (INE) or the Cadastre data.

Different public bodies have made available to the public spaces where they gather various data related to housing. This is the case of Barcelona City Council and its portal "Housing in data", an environment that centralises access to information and data from various sources, including datasets from its open data portal.

Another example is the Madrid City Council data visualisation portal, which includes dashboards with information on the number of residential properties by district or neighbourhood, as well as their cadastral value, with direct access to download the data used.

Further examples of bodies that also provide access to this type of information are the Junta de Castilla y León, the Basque Government or the Comunidad Valenciana. In addition, those who wish to do so can find a multitude of data related to housing in the National Catalogue of Open Data, hosted here, at datos.gob.es.

It should also be noted that it is not only public bodies that open data related to this subject. A few months ago, the real estate portalidealistareleased a dataset with detailed information on thousands of properties in Madrid, Barcelona and Valencia. It is available as a package in R via Github.

Tools and solutions to bring this data closer to citizens

Data such as the above can be reused for multiple purposes, as we showed in previous articles and as we can see in this new approach to the various use cases:

Data journalism

The media use open housing data to provide a more accurate picture of the housing market situation, helping citizens understand the dynamics affecting prices, supply and demand. By accessing data on price developments, housing availability or related public policies, the media can generate reports and infographics that explain in an accessible way the situation and how these factors impact on people's daily lives. These articles provide citizens with relevant information, in a simple way, to make decisions about their housing situation.

One example is this article which allows us to visualise, neighbourhood by neighbourhood, the price of rent and access to housing according to income, for which open data from the Ministry of Housing and Urban Agenda, the Cadastre and the INE, among others, were used. Along the same lines is this article on the percentage of income to be spent on rent.

Reporting and policy development

Open data on housing is used by public bodies such as the Ministry of Housing and Urban Agenda in its Housing and Land Observatory, where electronic statistical bulletins are generated that integrate data available from the main official statistical sources. The aim is to monitor the sector from different perspectives and throughout the different phases of the process (land market, built products, accessibility and financing, etc.). The Ministry of Housing and Urban Agenda also uses data from various sources, such as the Tax Agency, the Cadastre or the INE, for its State Reference System of Housing Rental Prices, which defines ranges of rental price values for housing in areas declared as stressed.

Offer of real estate services

Open data can be valuable for the construction sector: open information on land use and permits is consulted before excavation work is undertaken and new construction starts.

In addition, some of the companies using open data are real estate websites. These portals reuse open data sets to provide users with comparable property prices, neighbourhood crime statistics or proximity to public educational, health and recreational facilities. This is helped, for example, by tools such as Location intelligence, which provides access to census data, rental prices, housing characteristics or urban planning. Public bodies can also help in this field with their own solutions, such as Donde Vivo, from the Government of Aragon, which allows you to obtain an interactive map and related information of the nearest points of interest, educational and health centres as well as geostatistical information of the place where you live.

There are also tools that help to forecast future costs, such as Urban3r, where users can visualise different indicators that help them to know the energy demand data of residential buildings in their current state and after undergoing energy refurbishment, as well as the estimated costs of these interventions.This is a field where data-driven disruptive technologies, such as  artificial intelligence, will play an increasingly important role, optimising processes and facilitating decision-making for both home buyers and suppliers. By analysing large volumes of data, AI can predict market trends, identify areas of high demand or provide personalised recommendations based on the needs of each user. Some companies have already launched chatbots, which answer users' questions, but AI can even help create projects for the development of affordable and sustainable housing.

In short, we are in a field where new technologies are going to make it easier and easier for citizens to find out about the supply of housing, but this supply must be aligned with the needs of users. It is therefore necessary to continue promoting the opening up of quality data, which will help to understand the situation and promote public policies and solutions that facilitate access to housing.