Here’s a conundrum. You live on a busy main road. A nice man comes along and gives you £40,000 to refurbish your bedroom. You could do an awful lot with that — indeed, if you’re anything like me, you might think it would be hard to spend it all. But what’s the first, the very first, thing you would do? Yep: install the best soundproofing.

Not, it seems, if you were The Cumberland hotel. Their proud boast is that they have just spent £40,000 on every bedroom in the place, and they’ve made sure you can see where every penny went. Unfortunately, you can also hear where it didn’t, and if you’re at the front and sensitive to noise, you still can’t get a really good night’s sleep.

The Cumberland, a huge and venerable 900-room landmark bang on Marble Arch, reopened earlier this month after the most radical makeover a London hotel has seen for decades. At a total cost of £95m (yes, £95m), the grande dame that was, by common consent, slightly past her best, has been converted into the biggest “design hotel” Britain has ever seen.

The timing is, to say the least, odd. When the self-consciously trendy Sanderson and St. Martins Lane hotels revealed large accumulated debts last year, it confirmed for many what they had already suspected: the design-hotel fad was on the wane. All the emphasis on form too often meant that function took second place. It’s a dangerous strategy to sell a hotel mainly on its fashionability: fashions change, and when they do, you’re apt to be left high and dry.

But, like the penultimate scene in a Hammer horror movie, just when you thought the beast was dead, it has risen from the grave, bigger and more determined than ever. The management has carefully avoided using the term, but The Cumberland is now absolutely a design hotel after the Ian Schrager/Philippe Starck model.

It’s clear from the moment you enter the lobby. The function of a lobby, you might think, is fairly straightforward: to welcome guests, give them a place to check in, and to hang around and meet people, if they want. Not here. The lobby of The Cumberland is an art gallery — or, as the hotel would have it, “an art and design experience”. The enormous area is lightly studded with modern works by the likes of Sean Henry (Man with Potential Selves) and Marijke de Goey (The Waterfall — which is, naturally, a series of wall-mounted wire cubes).

What it doesn’t have is any feeling of cosiness or welcome, or, indeed, anywhere comfy to sit and chat. Apart from a lone padded bench, the only obvious seat is in the “sound pod”, which looks rather like a sofa inserted in a steel eggshell and plays specially commissioned recordings. So I sat in it. The recording sounded like somebody going to the lavatory. I got up again.

Whether business was particularly slow, or others share my view that it’s not much of a place to hang out, it’s impossible to say, but on the night I visited the lobby was hugely, embarrassingly empty. There were nine people in an area half the size of a football pitch, four of whom were staff and three of whom were statues. “The large open space creates an immediate sense of expectancy, possibilities and excitement” reads the blurb. Expectancy of some guests, maybe, and the possibility and excitement of them spending something.

After a drink in the eerily empty brasserie (it reminded me of the bar in The Shining, in spirit, if not in styling), I made for my room. There were Starckesque design touches everywhere — the light-box pictures, the disembodied hand offering two apples, the lopsided drinking glasses — which are fun if you like that sort of thing, but too much of it didn’t work properly. The television screen was enormous, but I had to turn up the volume to hear it over the roar of Park Lane. (After my stay, I put the noise problem to management, who said they now intend to install triple glazing.) The heating went wrong, the phone to the front desk didn’t work and, on top of that, for all its pretensions, the room felt like it had been done in a hurry. It was slightly tatty around the edges, with grubby window frames and slapdash paintwork.

It’s early days, of course, and any refit this radical will bring some teething problems. And, to be fair, there is one aspect of the design-hotel ethic The Cumberland hasn’t taken on board: snooty service. The staff are friendly and welcoming to a fault. Mind you, with so few people around, they’ve got plenty of time to spend on you.

The price of this “design experience”? Well, the published room rate starts at £325 for a rather small double, room-only, but when I phoned on spec, the hotel was happy to reduce that to £164.50. You could argue that’s not bad for being right in the heart of the West End, but it’s quite a lot to pay for being three years behind the times. If you do want to stay, take my advice: get a room at the back.

The Cumberland, Great Cumberland Place, W1; 0870 333 9280, www.thecumberland.co.uk

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