Refurbishment: Birmingham’s New Street station

The gleaming £750m station that has emerged from Birmingham’s gloomy New Street has been a triumph of logistics. But is it the icon the city was hoping for? Tom Ravenscroft reports.

Arriving at Birmingham New Street you now catch a glimpse of the shiny piece of urban bling that is the revamped station before disembarking on a clean and bright platform and progressing into a bright airy station concourse. Its former cluttered and dingy 1960s concrete confusion is such a distant memory that visitors may be forgiven for thinking that the building is an entirely new structure. The station, however, retains almost all of the bones of the original building, with several additions – most notable being the attention-grabbing cladding – and a great many subtractions.

Over the past five years Mace has transformed the UK’s second city’s central station. Internally, an entirely new concourse was built in the complex’s former car park and an atrium carved out of the existing slab to finally allow light into the building. Underground, the 12 platforms have been rejuvenated, and the entire building has been wrapped in polished steel cladding.

Described by Mace as Europe’s biggest refurbishment scheme, the impressive feat was completed while the station continued to operate at full capacity, with 140,000 passengers a day passing through the site and a train arriving or departing every 37 seconds.

Going underground

For anyone who has travelled to Birmingham in the past 10 years the need to rethink the UK’s busiest station outside London was obvious. Built in 1968 to replace a bomb-damaged Victorian train shed, the strange concrete beast was constructed at a time of declining passenger numbers and when the need for natural light was obviously a low priority. The 1960s strategy to push the tracks underground and cover them with a huge 2.8 ha concrete slab, upon which the station sits, created dark enclosed platforms.

Meanwhile, the decision to sell the air rights above the station to create the unmissed and unloved Pallasades shopping centre exaggerated the cramped feeling, leaving the dim concourse sandwiched between two heavy concrete slabs.

This utilitarian station was only designed to handle 60,000 passengers a day, but by the time the refurbishment started more than double this number were passing through. In simple terms, it was entirely unfit for purpose.

The new station (top) follows in the tracks of the first 1854 station (left) and the concrete 1960s rebuild (right)

“The station physically couldn’t cope with the footfall,” explains Carol Stitchman, Network Rail’s head of design for the Birmingham Gateway Project. “The constantly increasing pedestrian numbers were placing a strain on the station,
which was being forced to implement crowd-controlling measures, and even close the station doors at busy times.”

The refurbishment had twin aims. While Network Rail wanted to dramatically improve the customer experience of its current users and futureproof the station so that the anticipated growth in passenger numbers can be handled, the council had grander ambitions to banish the memory of the existing station and create a landmark for the city.

Network Rail and Birmingham City Council discussed a range of options, including a complete rebuild – an option dismissed due to the cost and the impact that closing the station for two years would have on the city. The decision was made to carry out a £750m refurbishment that would allow it to remain operational throughout.

But working in a live station environment was in some ways the least of Mace’s problems, although it meant that the operators’ train timetables in effect determined the programming of the build. “Even without keeping the trains running, the scale of the demolition and construction, amount of asbestos and lack of detailed drawings of the 1960s frame would have made this an extremely complex build,” says Paul Dalton, senior project manager at Mace.

Beyond improving functionality, Birmingham City Council saw the redevelopment as an opportunity to boost the city’s reputation and rejuvenate the city centre. Stitchman explains: “After we submitted the initial planning application the council suggested that we look again at the facade and atrium again to create something more iconic.”

Work on the dramatic central atrium (above) was carried out from the top down, with the tubular steel frame (below) constructed directly from the existing station’s roof slab, while passengers continued to travel

While Atkins retained its role for the design of the station proper, this desire to create a landmark led to an RIBA-organised competition to design an  eye-catching facade to wrap around the station’s existing concrete frame, along with a new atrium. The contest was won by Foreign Office Architects and after the winding up FOA, taken on by practice partner Alejandro Zaera-Polo. The result of this contest – a shiny steel facade – has grabbed much media attention as a love-it-or-hate-it piece of architectural marmite. However, it is behind this facade, in the heart of the building, that the most significant changes have taken place.

Most noticeably, the once-cramped concourse has been expanded to almost three and a half times its original size – it is now five times larger than that of London’s Euston (see plans, left). This atrium is accessed from three extremely wide entrances to the north, south and east of the station. The addition of an access point to the north connects the two sides of the city that were divided by bulk of original building and successfully wires the station into the fabric of the city.

“The way the station operates is fundamentally important to Network Rail,” says Stitchman. “Getting passengers moving efficiently into and through the station was the main priority, but the through routes are also important for Birmingham City Council’s regeneration strategy.”

Identifying pinch points

Internally, the design focuses on reducing the time passengers take to reach their platforms. Pedestrian flow analysis was used to identify pinch points that could create bottlenecks, such as the original narrow entrances, connections to the platforms and columns in the atrium.

Stitchman explains: “The original concept for the atrium had thin versions of the Stansted Airport columns. However, we found that each column could add three seconds to a journey, so these were removed to create a free-flowing space. The biggest thing was legibility. We had to manage the approaches and create a hierarchy of information. Information needs to be very clear when you are rushing to get a train.

“The station has been designed for a maximum capacity of 350,000 passengers a day, to futureproof it until 2035, so that’s why everything looks wide at the concourse level,” she continues.

The dramatic increase in the size of the main concourse has been achieved by expanding into a car park that originally occupied almost half of the footprint of the concrete slab above the tracks. This move unlocked the site. Before the old station was touched, an entire fully operational concourse was constructed in this space alongside the original station.

As Mace’s Dalton explains: “We removed a mezzanine level to create a double-height space that required complex strengthening of the existing concrete structure, then did all the internal finishes to create a functional concourse. Without the car park there would have been a high likelihood of disruption to station operations.”

Old to new: concourse-level plans

New Street Station 1964-2010

1. Car Park
2. Original concourse
3. Train operators’ offices
4. Original east entrance
5. Original south entrance
6. Retail
7. Offices

New Street station 2015

1. New concourse
2. New escalators to platforms (36 in total)
3. Escalators to shopping centre
4. New north entrance
5. Widened east entrance
6. Widened south entrance
7. Ticket office
8. Retail units
9. Offices

Working directly above the tracks meant Mace had severe restrictions on vibrations and the load that could be placed on the slab. Although the base could be used to work from, it could not support the 10 tonne pieces of concrete being removed from the mezzanine level. During the 65-week demolition process, rails were run the length of the building to support a gantry crane so that a “track and hover” system could be used to keep weight off the slab below.

Once this concourse was complete, the original one was closed and overnight passengers were transferred to the new building, allowing phase 2 – refurbishment of the original station – to begin.

In the refurbishment phase Mace’s major task was carving out the building’s main architectural event: the central atrium that allows daylight into the building. The original 2.8 ha slab was built in a grid of nine segments with the central section removed to accommodate the new atrium. Work started from the top and moved downwards. First a tubular steel frame supporting an ETFE domed roof was constructed directly from the roof slab. Demolition of this slab then took place under the new roof and finally the slab dividing the shopping centre and the station was removed.

To complicate demolition, a public walkway had to be maintained through the site, as although the concourses had been switched, the original stairs still had to be used for half the station traffic to access the platforms. As demolition could not take place directly above this temporary structure, it had to be moved halfway through the build. To make this possible, Mace developed a tunnel from prefabricated modular sections, with plug-and-connect M&E, which was then moved in 57 hours over a bank holiday weekend.

Adding the roof and removing a large volume of concrete, as well as hanging the new facades from the existing structure, changed the loads throughout the building. This required a global structural analysis to establish where strengthening needed to be undertaken.

Dalton says: “The load paths changed significantly throughout the building, both due to the demolition and the addition of a lot of dead loads. By the end of the build we have almost balanced out what we had put on and what we had taken out. But during the build the weight had dramatically increased, necessitating complex temporary works solutions.”

A large amount of work has also undertaken place below ground. Although the platforms are still devoid of natural light, the design team has done all it can to improve both their capacity and the passenger experience.

“We got rid of all the clutter and rationalised the platforms, removing waiting rooms, smoke lobbies and the former post office ramps. A comprehensive refurbishment was also carried out – with an enhanced smoke and fume extract system installed,” says Stitchman.

It was below ground that Mace’s planning had to be most accurate, as platform closures needed to be booked 18 months in advance. To allow the station to operate at full capacity, Mace tackled one platform at a time, with trains using the “closed” track to remove waste and to deliver materials. To increase efficiency while not being used, this train was parked at the platform so that the wagons created a safety barrier.

New connections were punched between the enlarged concourse and the revamped platforms – relieving a previous major pinch point. In the original station there were only two points of access to each platform. This has been increased to five, and the organisation rationalised so lifts, stairs and escalators are located in the same place on each platform. In total, 15 new lifts and 36 escalators were installed.

“The five means of vertical circulation from the concourse to each platform is the major change in the building,” says Stitchman. “By spreading the means of access throughout the station, you can now get people down to the platform efficiently and at the right place.”

Although the dire state of New Street meant that any attempt to refurbish would have been an improvement, Mace and Atkins (with Zaera-Polo’s input for the atrium), have created a fresh and bright station that operates extremely efficiently and surely fulfils, if not surpasses, Network Rail’s ambitions and expectations.

Shiny steel facade

Whether the building has achieved the landmark status that Birmingham City Council demanded is a harder question to answer. This question hinges on your opinion of Zaera-Polo’s new 16,000 sq m cladding. The shiny steel facade is formed of 5,000 panels, of which more than two-thirds are unique shapes, supported on a secondary steel structure attached directly to the existing concrete frame. The mirror-polished stainless steel certainly gives the station much-needed visibility, clearly marking its location in the city.

The mirror-polished stainless steel clad exterior (Paul Painter)

Unfortunately, the facade looks exactly like what it is, a clunky attempt to dress a tired old building in shiny new clothes. Zaera-Polo dissociated himself from the project as he believed that aspects of design – in particular the connection between the concourse columns and the atrium roof canopy – were being negatively impacted by Mace’s value engineering. He may have a point, but it’s more likely that a concept that looked stunning as a visualisation hasn’t really translated to reality. Perhaps this is a warning of the pitfalls of trying to commission an icon?

On the inside the building is a lesson in modern station improvement. However, from the outside there is no escaping the fact that it has simply redressed the existing concrete box. Given that it was built as a destination station, is completely integrated with the revamped shopping centre and has a direct link to the city’s first ever John Lewis, maybe the best advice for those arriving at Birmingham New Street is to stay inside the station.