How to complete a 138-year construction project


The latest #uandithink event welcomed Tristram Carfrae, structural engineer and Deputy Chair of Arup, to discuss the mammoth challenge of completing a 138-year construction project – La Sagrada Família.

U+I strongly believes in heritage as a driver for the regeneration and design of interesting buildings, spaces and places. As one of the world’s most well-known heritage projects, designed by one of the leading architects of the 20th Century, Antoni Gaudí, La Sagrada Família draws not only on its current status as a UNESCO World Heritage Site (since 1984), but also on its future legacy and contribution to the city of Barcelona and beyond.

Carfrae was commissioned in 2015 to lead on the final structural build of the grand cathedral with a target completion date of 2026; the centennial of Gaudí’s death. Beyond understanding the architect’s design decisions, Carfrae outlined the three key challenges to the build:

  1. By 2015, approximately 60% of the construction was completed, having taken 127 years. The remaining 40% was expected to be finished by 2026, requiring construction to be sped up by a factor of ten
  2. Certain aspects of the architectural design were impossible to be completed using traditional methods; the tower of the Virgin Mary, for example, sits directly above the crypt but the foundations would not have been able to support its weight
  3. How can we use what we know to maintain the quality of the build?

All three of these tests pointed towards the application of modern construction methods and rethinking construction in a way that advocated Gaudí’s architectural vision, while adhering not only to structural limits but also modern standards and regulations.

“Using BIM technology, we can now define every component to the millimetre; it can be modelled and specified, produced and then hand-finished. This combines up-to-date technology with craftmanship skills that haven’t changed for 1,000 years, giving elements a 1-mm tolerance while appearing to be hand-made as in all medieval gothic cathedrals,” explained Carfrae.

Commenting on whether he felt that Gaudí would approve of modern construction methods being implemented on his building, Carfrae was confident that the architect’s excitement for new technologies – evidenced by his experiments with concrete in 1926 – satisfy this concern. “We have little information on, for example, the Glory façade, because the design was incomplete when Gaudí died; the drawings are contradictory and many models were destroyed by fire during the Spanish Civil War. How do we interpret what Gaudí would have done – and whether that is what he would have done in 1926, or what he would do were he alive now?”

It is only by working with the existing material, and staying true to it, that the project can be completed in the most authentic way – for the benefit of the building and city itself.

A full recording of the event can be found here