Europe’s growing problem of homelessness could be solved at a stroke, say campaigners.
They point to the findings of a new study which has revealed that there are 11 million empty properties across Europe, including 3.4 million in Spain which tops the charts as the continent's worst offender.
In their opinion, all that needs to happen is a handover of some of these empty homes to people who are living on the streets.
The study was carried out by several organisations fighting against homelessness and was published in Britain’s Guardian newspaper this week.
With 3.4 million vacant homes, Spain has more than Italy, estimated to have 2.2 million empty properties, and Germany, which has slightly less at 1.8 million.
The UK has around 700,000 empty residential properties which could potentially be occupied while Ireland has 400,000 and Portugal 735,000.
Freek Spinnewijn from FEANTSA, a European-wide organisation that brings together national bodies fighting against homelessness, told The Guardian: “Even half of these empty properties would be enough to stop people from having to sleep in the streets.
"Governments should do as much as possible to put empty homes on the market. The problem of homelessness is getting worse across the whole of the European Union. The best way to resolve it is to put empty homes on the market."
The blame for the empty properties in Spain has been laid squarely at the feet of the housing market and its investors.
Spain's construction bubble in the decade before the beginning of the financial crisis was "fed largely by Britons and Germans buying homes in the sun," according to the report, leading to prices rising by 44 percent between 2004 and 2008.
Building companies worked at breakneck speed to create up to 800,000 new properties a year to keep pace with demand.
The 3.4 million empty homes in Spain represent 14 percent of all properties, according to last year's Spanish census.
Vacant houses and even entire 'ghost towns' can be found in parts of Spain after being abandoned by construction companies.
The problem is most acute in holiday resorts, some of which are still suffering from non-occupancy rates of over 30 percent some five years after the start of the economic crisis.
Part of the problem lies with Spain's high unemployment rate which has left many people unable to pay their mortgages. Repossessions of homes by banks has become a huge social issue in Spain, leading to mass protests and demonstrations.
Many local campaigners have demanded changes to the Spanish which leaves homeowners liable for mortgage payments even after losing their properties.
As banks continue to receive income, there is less pressure on them to put the houses back on the market.
María José Aldanas of Spanish housing and homelessness association Provivienda told The Guardian: "Spain is suffering from high numbers of repossessions and evictions, so we have reached a point where we have too many people without a home and many homes without people."
Banks have been accused of sitting on empty properties rather than lowering prices to sell them.
Critics say that this is done deliberately to artificially inflate the assets column of banks' accounts above true market value.
In the north-east region of Catalonia, some councils have reportedly warned banks that they will be fined by up to €100,000 ($138,000) if repossessed homes remain empty for over two years while others have threatened that they will be compelled to hand them over for use as social housing.