Ground vibrations during excavations on a Gżira construction site are believed to have caused the collapse of the façade and scaffolding on Tuesday, according to preliminary investigations.

The evidence collected so far indicates the excavations caused the foundations to vibrate, bringing down the entire façade, sources close to the investigations told Times of Malta.

The crash onto Triq Belvedere missed pedestrians by metres and once again reignited the discussion over the potential danger of the hundreds of construction sites dotted around Malta.

Four separate bodies are investigating the incident: the Building and Construction Authority (BCA), the Occupational Health and Safety Authority (OHSA), the police and a magisterial inquiry.

Sources said the investigators are in the process of collecting CCTV footage from nearby security cameras to potentially shed more light on what could have triggered the incident.

The footage would also determine the veracity of a claim that reached investigators that the scaffolding may have been hit by a passing truck. So far, none of the evidence has given credence to this theory.

Multiple sources said the site had all permits and related documents in order.

The original façade before construction works began. Photo: Google Street View taken in 2016

'Sound of crash was huge'

A witness who happened to be walking told Times of Malta that he was roughly 10 metres away from the site when the scaffolding surrounding the building gave way and the masonry of the façade followed swiftly, crashing into the balcony of the house across the street and spilling into the street below.

“I was listening to music on my headphones, but the sound of the crash was huge. There was dust billowing everywhere,” said the Gżira resident.

The resident said the building has been in the same state for several months, with just a façade holding on for dear life.

Developer Kris Calleja and architect Colin Zammit applied to demolish various properties on Triq Belvedere to build a hotel, which will include a new façade identical to the existing one, in the interest of “maintaining the visual rhythm” of the streetscape.

According to publicly available documents, the Building and Construction Authority issued a stop notice just after the collapse, “except to render the site safe”.

According to PA documents, the site technical officer is Pierre Farrugia, an architect who in 2019 was convicted of involuntary homicide when a young worker died in the reconstruction of the DB Seabank Hotel in Mellieħa. Farrugia has appealed the conviction, which is still pending.