On 1st December 2015 Transport for London (TfL) unveiled its new design bible, the Design Idiom. Though the name may sound grandiose, the goal is simple: create a document that captures the design aesthetic of the Underground, so that good design can help drive decision-making at London Underground.

“It’s all about bringing good design to the forefront of our thinking.” explains Mark Evers, Director of Customer Strategy at TfL. “Very simply, setting out the key principles that can help us deliver well-designed stations in the future, every time.”

“This Design Idiom is about taking that step back and making sure that in the future we are thinking far more holistically about the way we should be undertaking work on our stations.”

In practice then the Design Idiom will be a reference guide. As such it may seem strange to cover what is, effectively, an internal TfL document here. As our piece on the Johnston typeface has highlighted before, however, few transport networks in the world can boast the design heritage enjoyed by the tube, and thus few have such a high standard they should at least try to maintain.

Idiom Park, the fictional station TfL now use to convey design concepts.

An idea takes shape

Indeed it is an awareness of that history that has helped contribute to the Idiom’s creation. For in part it is a reaction to the celebration of London Underground’s 150th anniversary in 2013.

“There was lots of backwards focus on some really good architecture and good design: obviously the tube map, the font, the roundel, some of the Pick stations, the glorious days of Holden.” remembers Jon Hunter, Design and Print Manager at TfL. “And then we thought, actually, probably we need to reinvigorate some of the exciting times – the exciting energy – we had at the time.”

In essence, looking back at 150 years of design on the Underground had highlighted that London Underground had lost its way a little in design terms since the 1980s.

“Some of the stations we were seeing could have been any civic building with a roundel put outside.” Hunter admits. “We were becoming increasingly frustrated by the way our making a station look like a station [was] by putting a roundel logo outside and really it should look like a railway station.”

Every station on the Underground, categorised by design. Download full size image.

It’s a statement that an observer of TfL’s recent station builds and rebuilds would find difficult to dispute. Indeed in recent years it has become almost impossible to picture a new Underground station as being anything other than glass, brushed steel and concrete. A clean and efficient style, certainly, but hardly an inspiring one.

“If you think of the Holden and Pick era.” says Hunter. “If you think of St Pancras. If you think of a great London station there is a typology to them that is unmistakably transport, unmistakably rail.”

“So that is the focus that drove us to producing some very formal guidance – which hopefully isn’t too prescriptive that we end up with every station looking the same – but has some really core principles that should enable our next generation of new build and refurbishments to have more of a sense of London Underground about them.”

“You’ll look at them,” he says with a smile, “and you won’t necessarily have to see the roundel but you’ll see actually that’s a London Underground station. You’ll recognise it either through the design language, the use of interiors, the use of colours, the use of lighting, that it is actually one of our stations.”

Inside Idiom Park at ticket hall level.

As those behind the Design Idiom describe it, TfL’s aspiration was a bold one: to make sure that when London Underground celebrates its 300th anniversary, it is a unified aesthetic that is centre stage, not just Holden or Pick. Armed with this ambition and the drive to create consistently better design across the network, the organisation embarked on a three-year process to create a new language of Underground design.

“We spent a long time thinking to ourselves: ‘what is it about the stations that work that are on the network at the moment. What makes them special?’ ” Mark Evers says. “You can get lost in the excitement of designing something, but what is it that we want to do in this station. Actually you need to start with what our customers want: Where are the pain points for our customers? Which of our stations do they think most highly of? And, which of the stations do our customers think least?”

“By going through that process,” he continues, “we can identify common features and factors that customers like and then that is factored in when pulling together our principles.”

A station passage at Idiom Park.

Rolling out the programme

With arguably more station work underway on the network than at any point in the last thirty years, the opportunity to shape the design our era will be remembered for is perhaps now.

“Unless you give that proper consideration to good design both at specific locations but also how that fits into with the network,” agrees Evers, “you potentially find yourself ten, fifteen, twenty years from now looking back and saying: ‘well why didn’t we think more holistically about what we were doing?’ ”

With this in mind the Design Idiom is to be applied across the network from November onwards. Where possible, this will also include locations where work is already underway. Cannon Street station is to be the test bed and will showcase some of the design elements that are to become standard across the network, such as circular-framed customer information areas and more nuanced lighting design. New stations, such as Battersea Power Station and Nine Elms will then be built using the Idiom.

Nor will minor works at existing stations be exempt. The Idiom’s principles are to be applied to every station and on every intervention, from small-scale patch repairs to major refurbishments and brand new stations.

“The principles are instructions and should be used as checklist throughout the design process.” confirms Ann Gavaghan, Design and Development Manager at TfL.

Those principles are there to help everyone involved creates well-designed stations. In combination they are to ensure a holistic approach. There are nine in total, each of which highlights an area to devote particular attention to.

“We started off with probably about twenty.” Jon Hunter recalls. “Twenty principles is a bit too many to actually deal with. So we started combining them. There are only Ten Commandments so we thought: ‘if we go for less than ten, then we have more of a chance that people will actually use them and remember them.’ It’s much easier to say these are the principles, pull out the ones that are important and them in balance as well.”

Escalators at Idiom Park.

Hierarchy of customer needs

As Mark Evers indicated above, key to the Design Idiom is the belief that its nine principles should directly address customer issues. To help with this, TfL undertook research on customer perceptions of their built environment back in 2014. That research sought to understand what impact, if any, the built environment actually had on people’s travelling experience on the Underground. It concluded that the impact was significant. Nor, it found, was it just that passenger’s journey experience that was impacted. It had a clear effect on their perception of TfL itself.

The research’s headline finding was interesting. In 1943 American psychologist Abraham Maslow had theorised that human beings have a “Hierarchy of Needs”. That is, that our psychological health is predicated on fulfilling innate human needs in priority. TfL’s research suggested that it was possible to extend this principle into a hierarchy of customer needs that applied to its passengers.

It uncovered that at the most fundamental level passengers first ask themselves “Can London Underground get me safely and efficiently from A to B?” They then look for cues in the built environment to reassure them that minimum levels of safety and order are met. This makes those cues critical, as they are part of our basic expectation from London Underground.

Beyond this minimum expectation, people then look for a sense of order. They want strong clues as to how to navigate and to consume useful information as they move through the station. Then comes comfort, which includes an environment that encourages other customers to behave considerately and then finally life-enhancing elements such as signs that the station and the wider network are celebrating their heritage and feel connected to the wider community. All these elements are interlinked, whilst elements further down the priority chain are less effective if needs further up aren’t met. Comfort and life-enhancing elements of the built environment add value to the journey experience, for example, but are easily undermined if hygiene or safety factors are not being fulfilled.

The quantitative part of the research revealed that there are parts of that hierarchy that London Underground are failing to deliver in the eyes of their passengers. Most particularly, that they are currently underperforming with regards to the quality of customer information and the openness and orderliness of station environments. In contrast, the report revealed that London Underground are performing relatively well in the safety and sense of order categories, but less well on life-enhancing elements in stations. The research suggested that London Underground should improve in that category by making stations better reflect their local areas and by creating a positive atmosphere within them.

More than anything, the research highlighted the need for a holistic and well-managed action plan, which the Design Idiom is clearly intended to deliver. It also identified two clear cross-cutting themes: lighting and performance inconsistency. For this reason, it is perhaps not surprising that the Design Idiom has an entire principle dedicated to lighting, which the research suggests contributes to all levels of the customer needs hierarchy. Here, the Idiom has taken inspiration from how homes and retail are lit.

“Layer light, use light to draw focus.” it explains. “Make it intuitive so people know where the entrance and exits are. The exit is brighter of course.”

Lighting, it suggests, should also be used to reduce signage and clutter by creating zones of interest and subtly directing passenger movement. This doesn’t mean that it should be dull or standards rigidly adhered to without thought. In the past this has produced spaces with very flat and stark light where particular standard features are highlighted: such as customer information zones or areas with ticket machines. Instead the Idiom pushes for a more thought through, task-specific use of light. Just as we use light to create atmosphere within key spaces at home, it suggests, so should designers of stations.

Tackling performance inconsistencies, meanwhile, means dealing with problem design areas that have a habit of bringing down the whole experience. As the Idiom explains: “there remain inconsistencies in the quality of our station environments at every level of the hierarchy which undermine the pockets of brilliance, and ultimately drag down the overall customer experience. The Idiom helps to address these discrepancies and hits every part of the hierarchy in order to deliver outstanding customer environments”.

Overall, the Design idiom clearly epitomises TfL’s latest slogan “Good Design Makes Life in London Better”. It highlights that good design is about well-considered spaces and bestsuited interventions. It seeks to instil an approach of thinking about today, paying homage to the past and planning for the future.

Platform level at Idiom Park.

“[Well-planned spaces] are critical from an operational perspective.” Evers confirms. “You have got to make sure that they are able to get passengers through the station and onto trains, so that they can get to where they need to go.”

“But stations can be so much more than that.” he adds, thoughtfully. “If they are well designed it can make our customers feel safe using the network, irrespective of what time they are traveling. [A] well designed station environment actually changes the customer’s perception of journey time and reliability. If you are starting your journey in a station that, putting it bluntly, is a bit grubby, then irrespective of whether you are experiencing a great service it seems like it is taking longer and you feel like you are waiting on the platform for longer. Whereas if you are starting your journey within a station that has been well designed and is free from clutter it either has some wonderful heritage features within it, or some fantastic contemporary design – it makes that entire journey experience better for you.”

“The tube means so much more to Londoners than getting from A to B. We are a part of the city and what we want to make sure is that we are doing our best to make sure that life in London is getting better as well. A result of that is a real focus on design. I guess what we recognise is that great design doesn’t happen by accident.”

From train design to transport planning, you can find more articles about London transport in our archive.