London's mayor wants to start putting major roads into tunnels

Before and after: the A13 at Barking. Image: TfL.

Roads! Everyone loves roads, right? With their cars and their tarmac and their air pollution and that. Vroom vrooooooooooooom.

One man who has definitely decided we should be building more roads is London mayor Boris Johnson. This week he's in Boston and New York, because reasons, and has decided now is the perfect time to announce a clever plan to start burying bits of London’s trunk roads.

This is not as a crazy and idea as it might initially sound. They did it in Boston, byreplacing a six-lane elevated highway with an eight-line underground one. They're doing it in Hamburg, where the autobahn is being replaced with a park. They did it in that episode of Pigeon Street, too.

Sticking big roads in the ground has a number of advantages. It can reconnect neighbourhoods currently severed by main roads. It can make cities more attractive, if only because almost anything is more attractive than a great big bloody motorway.


And it can free up land for other uses – housing, office space, parkland, and so on. That, we suspect, is one of the reasons London's government is currently leaping on the idea. Not only does this mean more space to cope with London's population growth, but, with land values so high, the development opportunities will make any project a lot easier to pay for.

This morning City Hall said in a press release that it had examined "more than 70 locations... where the introduction of tunnels, fly-unders and decking could deliver benefits". That number looks a bit optimistic, though, and only five have been identified as "suitable for further feasibility work"; and several of these don’t sound terribly ambitious.

Nonetheless, here they are:

1) "Decking or a mini-tunnel" over the North Circular in New Southgate;

2) Turning the Hammersmith flyover on the A4 into the Hammersmith tunnel;

3) A "small fly-under" on the A316 at Chalker's Corner, where it meets the South circular near Mortlake;

4) "Decking of the A3 in Tolworth";

5) "A mini tunnel of the A13 in Barking Riverside", to connect one of London's biggest potential housing developments with something that resembles civilisation.

Here's a map, on which we've essentially highlighted the proposed developments in red crayon. (In an attempt to make them visible, our versions are almost certainly bigger than the real thing would be.)

To give a sense of the full scope of Boris' petrolhead ambitions, we've also included the three proposed East London river crossings: the Silvertown Tunnel, and Gallion's Reach and Belvedere bridges.

The really big one, though, is one Johnson has been talking up for a year: the proposal to create a whole new ringroad underground at a cost of £30bn.

What that would look like is not exactly clear. This is the version that was floating around when TfL first broached the idea last spring...

Image: TfL.

...but that doesn't seem to fit with TfL's response to a Freedom of Information request made by the blogger known as Boris Watch. That suggested the tunnel would be 70km long – roughly twice the length of the network shown in the map above. It also lists 10 junctions, including one labelled A10/A503, and another A23/A205, which strongly suggests that the loop would go as far north as Seven Sisters and as far south as Streatham Hill.

If that's accurate, then it seems likely the final tunnel would look a lot more like this. (We've labelled the junctions included in the modelling.)

The bottom line is that we don't actually know; neither, we suspect, does Transport for London.

But what is clear is that, for the first time in a generation, expanding London's road network is seriously back on the agenda – for better or worse.

 
 
 
 

Here’s how Henry Ford and IKEA could provide the key to solving the housing crisis

A flatpack house designed by architectural firm Rogers Stirk Harbour and Partners, on display at the Royal Academy, London, in 2013. Image: Getty.

For many people, the housing market is not a welcoming place. The rungs of the property ladder seem to get further and further out of reach. There are loud calls to build hundreds of thousands of new homes (and equally loud demands that they’re not built in anyone’s back yard).

If there was ever a time to introduce mass-produced affordable housing, surely that time is now.

The benefits of mass production have been well known since Henry Ford’s car factories made the Model T back in 1908. It was only made in one colour, black, for economic reasons. Not because it was the cheapest colour of paint, but because it was the colour that dried the quickest.

This allowed the production line to operate at faster, more cost effective, speeds. And ultimately, it meant the product could be sold at a more attractive cost to the customer.

This approach, where processes are tested to achieve increasingly efficient production costs, is yet to filter properly into the construction of houses. This makes sense in a way, as not everybody wants exactly the same type of house.

Historically, affordable mass-produced housing removed a large amount of customisations, to ensure final costs were controlled. But there is another way. Builders and architects have the ability to create housing that allows a level of flexibility and customisation, yet also achieves the goal of affordability.


Back in 2006, the “BoKlok” approach to affordable housing was launched to great acclaim in the UK. Literally translated from Swedish, the term means “live smart”. Originally created from a collaboration between flat-pack favourite IKEA and Swedish construction giant Skanska, the BoKlok housing approach was to allow for selected customisation to maximise individuality and choice for the customers. But at the same time, it ensured that larger house building components were duplicated or mass-produced, to bring down the overall costs.

Standard elements – wall panels, doors, windows – were made in large numbers to bring the elemental costs down. This approach ensured the costs were controlled from the initial sketch ideas through to the final design choices offered to the customers. The kitchens and bathrooms were designed to be flexible in terms of adding additional units. Draw and cupboard fronts interchangeable. Small options that provided flexibility, but did not impact on overall affordability.

It’s a simple approach that has worked very well. More than 10,000 BoKlok houses have now been built, mainly in Norway, Sweden and Denmark, with a small number in the UK.

But it is only part of the architectural equation. The affordable housing market is vital, but the cost of making these homes more adaptable is rarely considered.

Flexibility is key. The needs of a house’s inhabitants change. Families can grow (and shrink) and require more room, so the costs of moving house reappear. One clever response to this, in BoKlok homes, has been to allow “built in” flexibility.

Loft living

This flexibility could include a loft space that already has flooring and a built in cupboard on a lower floor which can be simply dismantled and replaced with a “flat-pack style” staircase that can be purchased and installed with minimal disruption to the existing fabric.

Weeks of builders removing walls, plastering and upheaval are replaced by a trip to the IKEA store to purchase the staircase and the booking of a subcontractor to fit it. The original design accounted for this “future option” and is built into the core of the house.

The best approach to new affordable housing should consider combinations of factors that look at design, materials and processes that have yet to be widely used in the affordable housing market.

And the construction sector needs to look over its shoulder at other market places – especially the one that Henry Ford dominated over a century ago. Today’s car manufacturers offer customised options in everything from colour to wheel size, interior gadgets to different kinds of headlamp. These options have all been accounted for in the construction and costing of each model.

The ConversationThey share a similar design “platform”, and by doing so, considerably reduce the overall cost of the base model. The benefit is quicker production with the added benefit of a cost model that allows for customisation to be included. It is a method the construction sector should adopt to produce housing where quality and affordability live happily together.

David Morton, Associate Professor in Architecture and Built Environment, Northumbria University, Newcastle.

This article was originally published on The Conversation. Read the original article.