Hanif Kara reveals why he is so seduced by RSHP’s Leadenhall Building
Towers evoke a response in society that mixes optimism, progress, pride, bemusement, bafflement and a touch of awe like no other typology. As a structural engineer, I will surprise no-one by picking one of my two favourite ‘hip not bling’ towers – Leadenhall Building and St Mary’s Axe – as my icon. My choice is Leadenhall, both for the purity of its expression of steel and a profile that avoids crowding the sky – while beautifully exposing the construction method.
It delivers a lot (1 million ft2) with an inviting public realm and technical indexes beyond the conventional, but it’s the muscular steelwork I most adore, delivering a structural order with a megaframe where each floor steps 750mm. This took precision of design, fabrication and planning to another level.
My early days on oil rigs give me a good measure of the gigantic forces the engineer has dealt with, in particular the design of the connections which will have exhausted the best brains at Arup, which were continually directed by the surgical scalpel of Graham Stirk’s relentless talent of working from the detail out. Contractor Laing O’Rourke and steelwork contractor Severfield both clearly and passionately delivered.
Engineers talk about the additional structural optimisation that would have been possible if the primary bracing had faced the opposite way, but to me that is minor conversation. Guided throughout by British Land construction director Richard Elliot, the final result is almost an industrial product, a compelling masterpiece that will be a springboard for us all in many ways.