Terence Conran: The Way We Live Now, Design Museum, London

Conran didn't start the sexual revolution – he just sold us the kit...

Emerging from the loos of a bar the other day, I told my friends they should see the funky taps in there.

The water, instead of coming out of the spout, ran along the top of the spout and over the end.

They all filed in, but came back unimpressed – they'd seen better elsewhere, they sniffed.

I was reminded of that shoulder-shrugging by this exhibition to mark Sir Terence Conran's 80th birthday. It strikes you just how used we have become to finding exciting design in even the most mundane places. Sixty years ago, when the Habitat founder and restaurateur was starting out, taps were for dispensing water, not to provide a talking point. Today, house-builders will fit a dinner-plate showerhead as standard.

The Design Museum suggests we have Conran to thank for that. From an early age, he cared about good design, and wanted the world to care too. He made his first bookcase aged 10, and got a lathe the year after. A visit to France in 1953 confirmed his belief that food and furniture could be exciting: here were colourful fruits and vegetables, simple but stylish kitchenware, and brocantes teeming with attractive cheap furniture. He came back to spam-fritter Britain determined to spread the word.

Whatever you think of Sir Terence the man today – the self-important, cigar-chomping, thrice-divorced Blairite luvvie – this show is an attractive and thoughtfully arranged reminder of just how much he has achieved. Take Habitat, the interiors store that he launched in 1964. It was born out of frustration that retailers were reluctant to stock his minimalist designs, and proved an instant hit, providing affordable contemporary furniture to home-makers hungry for something different from the dark wood and Dralon of their parents. A display of catalogue covers from 1971 to 1990 shows the speed and boldness of change: by 1977 there were 25 branches; by 1986, 52.

Habitat wasn't just a commercial success – it reflected the cultural revolutions of the 1960s, and facilitated the new way of living. Is there a better symbol of sexual liberation than the duvet? Gone were layers of tightly tucked sheets with hospital corners; access had just got a lot easier.

British eating habits were changing too. Elizabeth David published French Provincial Cooking in 1960, but nobody owned a garlic press. Habitat stepped up once again, supplying an adventurous British public with the equipment they needed to try new foods. Each new gadget generated a wave of excitement: The pasta-maker! The fondue set! The wok! The entire props list for Abigail's Party is here.

The question is, which came first, the chicken or the chicken brick? Did Conran actively shape domestic habits, or was Habitat a happy accident, the catalyst that enabled change to take place? In Scandinavia, a parallel story was unfolding with Ikea, which didn't hit these shores until 1987.

Conran's success came from being both a designer and a businessman. "Good design is 98 per cent common sense and 2 per cent aesthetics," is his mantra. He also said he would never design a piece of furniture that he couldn't make himself. Bear that in mind next time you're grappling with a Habitat flat-pack.

Except, of course, Habitat is no longer; it went into administration last summer. Only three stores survive, and Conran's association with the company ended in 1990. The exhibition moves on to his other major legacy: how Conran helped reinvent the British dining experience. Here is a gorgeous, simple, colourful menu, designed by David Hockney. Here, a 1965 photograph of the interior of Fortt's kitchen in Bath could be of any Zizzi or Strada, all sexy banquettes and elegant chairs. How different from the average chop house.

You could come away thinking Conran was responsible for the entire cultural revolution of the Sixties. But then, this show was never going to be less than partial: it was he who set up the Design Museum in 1989, he owns the building and is donating £7.5m to help it move to premises three times the size in 2014. So this feels like a farewell, though Conran will be involved in creating the new premises at the former Commonwealth Institute. Leaving this converted banana warehouse on the Thames will be sad, not least as one of Conran's best restaurants, Le Pont de la Tour, is next door. Then again, it is slightly let down by the loos. I've seen better elsewhere.

To 4 Mar (020-7940 8790)