There are only a handful of gasholders remaining around the UK, most of these hulking structures have been demolished to make way for new developments. They may not be everybody’s idea of beauty, but gasholders are a rapidly disappearing reminder of our country’s proud Victorian heritage.

The Triplets are Grade II listed, their wrought iron and riveted lattice girders were dismantled and painstakingly repaired before being reassembled around a series of apartment buildings on the King’s Cross site, which is the largest urban redevelopment scheme in Europe.

Wilkinson Eyre Architects were tasked with providing the design to transform these 1860s structures into new flats complete with roof gardens, and they have done a magnificent job of making the most of these elaborate cast iron frames.


Incorporating the Triplets into a brand-new development was no mean feat, with three tiers of hollow cylindrical cast iron columns, cast iron capitals and three tiers of wrought iron riveted lattice girders to take into account. The architects’ concept proposed three circular buildings of differing heights to mirror the movement of the original gasholders, which would have risen up or down depending on the pressure of the gas within.

PUDLO was involved with this project from the design phase and, since the basement construction phase commenced in 2015, continued to be present onsite throughout. The PUDLO on-site guidance proved valuable along the way for the podium deck, basement car park and lift pits which were all poured using PUDLO concrete. With Henry Construction heading up the below-ground PUDLO work, and A.J. Morrisroe taking the reins for the PUDLO podium deck above ground level, a seamless meeting of minds was essential during this project. PUDLO worked closely with both of these contractors to ensure the concrete was placed correctly and their shared wall joint remains waterproof.


The Triplets now house high-value market residential units as well as retail units on the ground floor and a restaurant on the top floor. The Triplets are the world’s only connected triplet to be refurbished into residential spaces.

They now sit further north than their original footprint, just north of Regent’s Canal; a stunning setting that provides the Triplets’ residents with views of the water and a nearby nature reserve. Being so close to the canal and railway lines, it gives a touching nod to the original setting of the Triplets and was approved by English Heritage as the most appropriate spot for these colossal industrial symbols.