Heatherwick Studio

Argent LLP

BAM Construction

Scope & Products:

• BIM Integration and PCSA Design
• Steel Curtain Wall Shop Fronts – 3.5m High x 5m Wide
• Curved Head Screens
• Seamless cladding of steel beams
• Automatic Door
• Dual action door with emergency breakout feature
• Fire Rated curtain Wall
• Fire Rated core doors
• Shop fronts with Plenums to allow ductwork connections by the shop fit out
• NEW Emergency break-out developed by Propak and patent
• Steel bi-fold doors
• 4m high thermally broken arched panes of glass


• Glass was incredibly bespoke with high G-Value requirements, extremely low iron content and U- Value requirements limiting the number of suppliers able to produce the specification required with such a large span of glass.

• Some panes were arched at the head and 3.5m tall by 3m wide.

• Glass handling of such large panes required specialist in-house team.

• Glazing large panes at second floor level had to be done using cranes positioned on the ground floor

• Managing deliveries from the continent – timing and project management essential due to limited storage onsite.

• The arches were rolled individually in Germany so scheduling required to maintain constant manufacture

• Our first project with full BIM integration

• 160 plenums manufactured from steel sheet metal; the curved of the plenum hand rolled to match the radius of the curtain wall that it was being installed into.

• Design intent require the sightlines to be kept to a minimum and the back box of the curtain wall to be as small as possible – Propak were able to design a solution with a 50mm face width and 80mm back box.

• Managing international deliveries of over 400 pieces of glass scheduled in separate 8 deliveries over a 4 month period


Winner of the RIBA London Award 2019 and RIBA National Award 2019 – Coal Drops Yard is certainly one of the most iconic buildings in London with its canalside setting, Victorian architecture and rich ironwork. It is home to over 50 stores and restaurants in a reimagined set of historic buildings and arches directly adjacent to Granary Square and Regent’s Canal.

Originally established in 1850 to handle the eight million tonnes of coal delivered to the capital each year, Coal Drops Yard was latterly the location of nightclubs Bagley’s and The Cross.

UK property developer Argent worked with London architect Heatherwick Studios to create this fantastic new shopping district. It’s founder Thomas Heathwick, who received national acclaim for his interpretation of the Olympic cauldron at the 2012 Games, is also the brains behind London’s Garden Bridge, New York’s Pier 55, and Google’s new headquarters amongst.

Coal Drops Yard is the latest chapter in the £3bn redevelopment of King’s Cross where developer Argent has been transforming railyards, gasholders and warehouses into offices, restaurants, shops, public space and the campus for Central Saint Martins.

Propak was proud to work with main contractor BAM on the preconstruction phase of this heritage project. Over 100 shop fronts were manufactured and installed including over 400 panes of glass – some were arched at the head and 3.5m tall by 3m wide!

While an automatic door system was originally proposed for each archway, Propak came up with a far more original concept that not only saved over £350,000 on the build but is one of its kind on the market.

The team designed a system completely concealed in the head of the doors which allowed them to open inwards during normal use and break out in the case of emergency. This design is now available from Propak and is in the process of being patented.

Steel was a perfect fit for this industrial looking building due to its robust properties which we were able to manufacture in-house via Propak Sheet Metals with a face wide section of just 50mm and back box of 80mm. But with spans of up to 5m on single mullions, the sheer size and weight of the glass and extreme wind loads imposed on the structure of coal drops – which essentially created a wind tunnel -we had our work cut out to maintain the smallest sightlines possible. Our structural engineer helped develop reinforcing spigots to meet this design requirement.

As each arch had completely different radius and spring points they were often lower on one side than the other so each piece of sheet metal had to be individually rolled and manufactured to match the Victoria hand built archways.

Working on a heritage site is not without its challenges – there were always deviations in the brick work of the Victorian archways and differences in a true radius to what had been built (of up to 40mm) but this had to stay in place.

To overcome this Propak researched and developed an angle that clipped under the external pressure plate to create a shadow gap hiding these deviations.

Being a heritage site the original brickwork had to stay in place. Using our sheet metal engineer we came up with a method of laser cutting a Skelton shape into the angle so that the curves could be formed on site and packed away from the cover cap allowing us to match the archway.

Demonstrating our commitment to the project and ongoing commitment to safety in general, Propak upgraded our fleet of vehicles with safety systems and camera to meet FORS Silver – a requirement for this project.

This was a memorable project to work on, the third that Propak have undertaken in the area – one being a ‘feature’ beautiful copper clad door to Argents head office.

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