When there is a fire, is it met the goal of the CTE DB SI (National building code) ?

On August 29th 2020, we saw how a high-rise residential building in Madrid with the firsts lights of the sunrise was engulfed by the flames in the penthouse. This event inevitably reminded us other similar fire that occurred in the past such as Grenfell Tower in London, the fires in the Emirates, the Polat Tower in Istanbul and especially the Windsor Tower in Madrid.

At this moment, the information about the fire has only been published by the media, but the most important fact is that there have been no fire deaths nor injuries. This has undoubtedly been possible thanks to the excellent response of the emergency services involved, in these cases, coordination amoung all of them is very important.

But making a reflection on the future, we could ask ourselves if our national fire safety regulation, the CTE DB SI, is adequate in the light of a fire event like this. Due to the ignorance, some minority voices are heard who argue that the safety level of the CTE DB SI (National building code) is insufficient in case of fire.

In this sense, the first thing is to know the goal of the CTE DB SI.

Article 11. Basic safety requirements in case of fire (SI)

1. The goal of the basic requirement «Safety in case of fire» is to reduce to acceptable limits the risk that the users of a building may suffer damages derived from an accidental fire, as a consequence of the characteristics of their project, construction, use and maintenance.

2. To meet this goal, the buildings will be designed, built, maintained and used them in such a way that, in the event of a fire, the basic requirements established in the following sections are met.

Considering current information, the Madrid fire supposedly triggered by a barbecue in the rooftop. (The investigation will determine whether the circumstances surrounding the origin of the fire are considered an accident or not.) If it was an accidental fire, the evacuation process has been successfully carried out thanks to the compartmentalization that prevented the smokes and flames invade the stairs and evacuation routes. This is the true goal, the safety of the people. And, in this specific case, it has been achieved.

To achieve this goal, the CTE DB SI establishes a set of requirements whose fulfillment ensures that minimum security levels are exceeded. This is reflected in the following basic requirements:

    SI 1 – Interior spread.

    SI 2 – Exterior spread.

    SI 3 – Evacuation of occupants.

    SI 4 – Fire protection installations.

The media highlight that the fire alarm was disconnected at the time of the fire. It have to be confirmed by the official investigation.

Another aspect that we assume that the investigation will analyze is whether the façade system (exterior cladding and insulation) complied with the national requirements CTE DB SI applicable at the time of the Tower’s construction. In view of the images of the tower, the insulation used is glass wool (mineral wool) and the outer cladding is very similar to a metallic product of the ACM type (Aluminum Composite Material), with a filling that at the time of writing of this post has not yet been determined, but a priori it has contributed to the spread of flame with falling flaming droplets.

In our guide «Fire safety in facades«, we explain the reasons why façade fires can affect any type of insulation and we try to offer solutions to evaluate adequately the façade behaviour in case of fire, as well as the importance of taking into account other measures.

On the positive side, the media indicates that the firefighters successfully used the dry riser to attack the fire from the inside, and the accessibility to the building seems to have been adequate given that the fire fighters could use two trucks with a stair height of 70 m to attack the fire spread from outside.

Consequently, due to the facts found and the provisional information, the goal of the national regulation CTE DB SI has been met despite the alleged aggravations that the tower could have at the time of the fire. This shows, that the requirements provided an adequate level of security to guarantee the evacuation of people. The fire safety of a façade and the evacuation of people depends on many factors.


Diseño de Instalaciones de Protección contra Incendios (PCI)