Spain: 1.2M building records to check for flammable cladding

Unknown number of buildings have flammable facades: records are on paper

No one can say how many buildings in Spain have flammable cladding. This is not a casual opinion but an admission by the Official College of Architects of Madrid trinc a fire in Valencia that killed ten people. The institution summarizes the situation with a worrying image: counting them is like counting grains of sand on a beach. Thousands of structures could be at risk, and current tools make it impossible to know for sure.

Why is it impossible to know how many buildings use polyurethane?

Because paper rules. Until 2006, submitting the building log—a document recording construction materials—was not mandatory. Before then, a favorable technical report sufficed, so there is no material record for most buildings constructed prior to that date.

Post-2006 records are also problematic. These building logs are extensive, often exceeding **1,000 pages**. Many were submitted on paper and remain undigitized, meaning identifying facades hiding polyurethane requires manual review of each volume. The Ministry of Transport and Sustainable Mobility counts **1,230,703 buildings** constructed since 2006. Each one must be checked individually.

Administrative complexity adds another layer: each municipality keeps its own construction registry. Gathering these records to monitor dangerous materials is a task that, given available data, will take more than a few weeks.

The BIM standard discussed for 30 years but never implemented

The irony is bitter. A methodology called BIM (Building Information Modeling), designed to index and make construction data searchable, has existed for decades. It has been promoted for thirty years, yet files still sleep in municipal archives.

Some argue that digitizing relevant data as files arrive would suffice, suggesting the issue is lack of will rather than resources. Others note that firefighters should have immediate access to critical information for every address they visit. Today, they do not.

What actually burned in the Valencia building?

Here, quick narratives diverge from technical analysis. Some experts claim the insulation was not polyurethane; images from the fire and 2008 Google Maps suggest **rock wool**, a non-combustible material. What likely burned was the 3-millimeter inner lining of the finish panel, made of polyethylene.

This detail matters because the calorific value of this inner panel material is **43.4 MJ/kg**, identical to gasoline, according to calculations cited in the debate. Aluminum composite panels with polystyrene cores were legal across the Eurozone until recently, only facing scrutiny after the Grenfell Tower disaster. Unproven theories about arson also circulate regarding the Valencia incident.

It is essential to remember: polyurethane is a legal material. Its use is regulated, and its presence in building logs does not imply irregular construction.

From 1970s SATE systems to chimney-effect facades

The issue extends beyond one building. External thermal insulation composite systems (SATE) using extruded polystyrene have been installed in entire housing developments from the 1970s and 1980s for years, burning intensely. Technical analyses point out that most such solutions lack an air gap between the finish and insulation, avoiding the chimney effect seen in ventilated systems.

Aesthetic wrappers are also criticized: aluminum and composite panels often serve merely to cover prefabricated concrete walls raised quickly. Decoration posing as exclusivity behaves like decoration when fire strikes.

Who pays for new facades?

The British precedent weighs heavily on discussions. After the London tower fire, owners of homes with flammable facades had to pay for recladding themselves; until then, they could not sell properties, obtain new financing, or insure them affordably. The prevailing sentiment is that the same script will repeat here: no one will be held accountable for approving combustible materials, and costs will fall on community bills.

The trap of expensive, old housing

An underlying economic thread is often ignored. Current prices leave no funds to renovate old housing stock, especially poor work done during the boom. Arguments suggest prices should be much lower to make rehabilitation viable, but market demands render any special assessment fees unrealistic. Energy certificates and European environmental regulations appear in interventions as origins of measures aimed at saving energy costs, not ensuring safety.

However, probability is the uncomfortable argument: if thousands of buildings are in similar situations and only one burned, something specific peine there. Or, viewed differently, the rest have simply been lucky so far. With paper records, legal but disputed materials, and blameless owners, the next audit will likely come only after the next fire.