Aluminosis: how to tell if your building has it before you buy or sell

Aluminosis is one of those words that frightens people buying an older flat. But you can narrow down the risk in seconds with a piece of data that is already in the Catastro (the Spanish property register): the year of construction.

What aluminosis is

Aluminosis is a defect in concrete made with high-alumina cement, widely used in Spain between 1960 and 1975, especially in Catalonia. Over time and with damp, that cement can lose strength and compromise the beams. Not every building from that period has it, but the period is the first risk filter.

The first filter: the year of construction

The key figure is public and free: the year of construction recorded in the Catastro. If the building dates from 1960-1975, it falls within the risk window and it is worth ruling out high-alumina cement before closing anything.

You can look it up on the Catastro's online portal (Sede Electrónica) using the cadastral reference or the address. At La Llave we do it automatically: the report flags the property with a «possible aluminosis risk» warning if the year of construction falls within that period.

How to really confirm it

The year only gives you a suspicion. To confirm or rule it out you need a technical inspection:

• A certificate from a qualified professional (architect or building surveyor) who analyses the structure.
• Tests on the beams (core samples / chemical analysis of the concrete) if there are signs.
• Review the building's history: a recent, favourable ITE (Building Technical Inspection) is a good sign.

What it means for the price

A building with confirmed, unrepaired aluminosis loses value and makes financing harder. But one from the same period whose structure has already been repaired and certified is perfectly normal — even an advantage, because that problem has already been solved and documented. The key is to know and document it before negotiating.