HS2 has completed six 450m platforms for high-speed trains at Old Oak Common in west London.
The platforms are being built within the station’s underground box on Old Oak Common Lane. The wider station will also include eight conventional platforms for Elizabeth line, Great Western Main Line and Heathrow Express services.
Platform construction
HS2’s station construction partner, Balfour Beatty Vinci Systra (BBVS), oversaw the platform works, with subcontractor Expanded carrying out construction.
The work involved casting 1.59m-high invert walls in situ before lifting and securing precast platform slabs manufactured by Explore in the East Midlands. The six platforms required 1,946 slabs, each measuring up to 2m by 4m and weighing between 4t and 5t.
Construction progressed simultaneously from both ends of the station box, with the teams meeting in the middle to form three island-style blocks. A void beneath the platforms will provide space for services including electricity.
“It was a really complex operation to pour all the concrete, it was very well phased,” said HS2 senior project manager Russell D’Urso. “We started at the top and excavated halfway down before building the intermediate level of the station and then excavating the final stretch.”
The works required temporary structures to support the walls, alongside extensive safety monitoring. BBVS project director Steve O’Sullivan said: “There were lots of temporary structures we put in place to stop the walls from falling in. There was a great amount of safety monitoring too.”
Heat and tunnelling
Recent high temperatures have also affected the construction programme. Concrete pours were brought forward and reduced in size, with the team drawing on practices used in hotter countries, according to D’Urso.
“We had to start pours earlier and pour less over the last few weeks due to the weather,” he said. “We’ve been learning from other countries with hotter climates how to navigate the heat we’ve been experiencing here lately.”
HS2’s London tunnels contractor, Skanska Costain Strabag (SCS), is due to break through the western wall of the station box by November. The tunnels will connect Old Oak Common to the Northolt Tunnel and the wider HS2 route to the north.
Two tunnel boring machines launched from the station box at the start of 2026 are expected to reach Euston in 2027. The Euston Tunnel will eventually link Old Oak Common with HS2’s planned central London terminus.
O’Sullivan said the Old Oak Common project was being used to share lessons with the Euston development team. The station team has also benchmarked its work against projects including Whitechapel, built for the Elizabeth line, and London Bridge, rebuilt for Thameslink.
Conventional platforms and roof
Work is continuing on the station’s conventional platforms. The existing Great Western Main Line track must be realigned to serve the new station, but the work requires a blockade extending to Paddington.
HS2 project client director Dave Lock said the blockade was being negotiated with Network Rail and was not expected before 2029. It will last for up to 12 days, allowing the existing railway to be lifted and the replacement alignment to be constructed.
The first slabs for the overground platforms are due to be installed later this year, while the first section of the station’s large roof is scheduled to be installed early next year.
A heavy-lift crane used to build the station box was described as the world’s heaviest load crane. An even larger crane will be procured for the roof installation.