Is this the perfect chair?

A radical new office seat was inspired by the complex engineering of the Golden Gate Bridge. Josh Sims hears about its creation – and why it's so modern

One is 8,981ft long, 90ft wide, 220ft high and weighs 60,000 tons. The other is 25in wide, 17in deep, 36in high and weighs 37lb.

At first glance the latter, a new chair by the acclaimed designer Yves Behar, and the former, the Golden Gate Bridge, may appear to have nothing in common. But it was staring from the window of his design office window at the San Francisco landmark that gave Behar a radical idea in chair technology: what if a chair could be built to mimic the suspension system of the bridge?

"The suspension idea must have been considered before but I think it's only because technology has moved on that it has has become possible to translate that into something to sit on," says Behar, who recently won a prestigious prize for his One Laptop Per Child laptop design and is noted for his work for BMW, Coca-Cola and Canal+. "We wanted to remove as many elements from a standard chair design to make it lighter and more affordable, so the attention became focused on the frame, which typically tends to reduce the ergonomics and add materials. And since a suspension bridge is essentially frameless ... "

Some 1,000 sketches, 70 prototypes and $13m later, the result is the Sayl, launching in the UK next spring. It is arguably the most technologically complex yet materially simple chair to date from the American furniture design giant Herman Miller, which counts the likes of Charles and Ray Eames, George Nelson and Isamu Noguchi among its past collaborators (and the invention of the office cubicle among its more dubious offerings). Some of the chair's design detail is proprietary and Herman Miller – which generates some $1.3bn in revenue from its chairs every year – is not about to give away details that might dent its share of the office furniture market, one worth £670m a year in the UK alone. But in essence Sayl comprises a Y-shaped strut – like the Golden Gate's towers – made of glass-filled nylon and over which is stretched a web of elastomer, an injection moulded plastic similar to the kind used to make the soles of trainers, but which in this case has taken a team of 20 engineers nearly three years to develop.

Each strand of the plastic has been individually designed to microscopically different thicknesses, subject to some 1,300 calculations, so that the tension across the web is variable – stiffer and stronger at the centre, where the back needs most support, but more flexible at its sides, allowing it to mould to the individual's posture rather than, as with most chairs, forcing the sitter's posture to adapt to the chair. Vertical strands support the spine, while lower, horizontal ones provide lumbar support. A trampoline effect – and machine testing that pulled and pushed each strand 1.5m times – ensures the web bounces back into form to support the next body. "It may look lightweight, but it still needs to carry a 300lb person," Behar notes.

The design also follows what Behar calls a dematerialistic approach: handles and other parts were hollowed out where possible, reducing materials used by 45 per cent compared with a typical office chair. Where the seat structure is usually four or more parts bolted together, Sayl uses one part. Similarly, while a more standard office chair's back comprises up to five layers of materials, Sayl has one, which arguably does more than the standard several do together.

That also provides Behar's answer to the pressing question: does anyone actually need another kind of chair, even a designer one? "Chairs can be made in a much more technologically-advanced way than they were even just 10 years ago, and it's important to redesign everything according to the technological resources available," he suggests. "A chair is still one of the greatest design challenges – it has to be structurally and ergonomically functional, but there's nowhere to hide. The design of a car is essentially hidden under a shell, but that of a chair isn't just exposed, it's felt in your body."

Behar's approach means the Sayl – named in reference to the sail-type look of the chair's back, with the spelling a nod to the shape of its support strut – is not only especially comfortable, but 30 per cent lighter than previous chairs from its maker and a third of the price (at £350), allowing the company to reach what it hopes will be a wider customer base, especially the growing number of people who have home offices. As Bret Recor, Behar's technical director, notes: "It needed to be a radical use of technology to make the idea of a mass-market chair of this standard genuinely affordable. The famous plywood chair that Herman Miller developed for Eames was meant to be a chair for everyone. And if they were around today they'd be freaking out at what it sells for."

Not to dismiss the aesthetics, the Sayl is also one of the most stylishly arresting chairs anyone is likely to plant their rear on nine to five, especially since the webbing can be made in any colour and the science is on show. It is the iMac of the chair world.

The big companies in this market are good at taking what they know and improving on it, but historically they're not good at taking new technology and applying it to new ideas," explains Jack Schreur, Herman Miller's head of seating. "With this we started at the chemical science level to look for a substance that gave the right combination of strength and flexibility. Our engineers told us they could get there but weren't sure how long it would take. It was, they said, like playing 3D chess: you tweak one tension and it changes three others you didn't want to change.

"Obviously there's a limit as to how long we can commit a team that size to looking. We were lucky. And, of course, whereas we might develop such a technology, put it in a chair and cover it with some surface material, it takes an Yves to say, 'Why not just make it the surface?' just as it can take an outsider to see that applying a bridge structure to a chair makes sense – after all, a suspension bridge supports, it looks great and it's a recognised form."

As well as already breaking the company records for advance orders, the Sayl is a timely chair, its stripped-down approach touching on the vital need for more sustainable design (it will also be manufactured in three continents, to minimise the carbon footprint of transportation) and, although the project was launched before the recession, its lower price now looks rather prescient. But Behar argues that his design also works symbolically.

"A new chair isn't just technologically innovative but has to also reflect the ethos of work in the times it's made," he argues. "Work today is very different to how it was even just a few years ago. The time was when an office chair was a statement of status – the higher up the chain you were, the bigger and more padded your chair and the higher its back. We expect more transparency and more horizontality in the workplace now, and the office chair needs to express that.

"People tend to be unknowing experts in chairs – they respond intuitively and immediately to one every time they sit on it," Behar adds. "But people also need to understand what a chair design stands for, and how technological its design can be. Sayl is a stepping stone and we can expect even more technologically-advanced chairs that are even more responsive, visually lighter, simpler still. They will really astound – and when people realise the technology that goes into a chair like the Sayl they already tend to fall off the one they're sat on."