Ben Elliot's plan to save Soho

My first attempt at raising money for a good cause this year ended in hospital in France. In July, I set out from London to Paris on a bicycle in the spirit of Lance Armstrong. Twenty miles outside Dieppe, in a raggle-taggle peloton, I came a cropper when a fellow cyclist went straight into me.

I made an Eddie the Eagle arc and fell spectacularly, dislocating and breaking my left shoulder, my Lycra and dreams in tatters. To add insult to injury, the culprit, an anaesthetist from the West Country, tried to pop my shoulder back into its socket (clearly he'd seen too many Mel Gibson movies). I hope my second attempt is more successful.

In February, I found myself idly walking down Greek Street towards Soho Square, a walk I have made many times. Soho has been my concierge company Quintessentially's home for nearly ten years. And during that time one building has always leaped out at me: the magnificent 18th-century House of St Barnabas on the corner of Soho Square and Greek Street.

I had heard of its garden, an inspiration for A Tale of Two Cities, and I knew it had a mysterious crypt. Plus, a Soho roué had told me it was the House of Fallen Women, which only added to its Dickensian appeal. But until that day I had never knocked on the door.

It was answered by a young woman, a volunteer at the charity that operates there, and has done since 1846, assisting the home less through a skills programme that helps to rebuild their lives. The House had been her home when she - an alcoholic and drug addict who had been ostracised by her family and friends - had none.

She was one of the last fallen women to live there. A fire three years earlier had gutted the House and the charity's trustees couldn't afford to rebuild it for use as a refuge. She showed me a scrawl above the Gothic fireplace in just one of the extraordinary Georgian rooms: 'I was a stranger and you took me in.'

She was a stranger and they took her in; she had taken me in and I was a stranger. Thanks to the House of St Barnabas, she started at university this term studying social care. Walking back to our office on Carlisle Street, I counted 23 homeless people in 250 yards. We needed to become better neighbours, fast. As the government runs out of money, charities such as St Barnabas have to stay afloat.

The name Soho first appeared in the 17th century. Some believe it derives from a hunting cry; the Duke of Monmouth used 'soho' as a rallying call for his men at the Battle of Sedgemoor in 1685. This has been uppermost in my mind as I have rallied, begged and cajoled everyone I know to restore the House of St Barnabas to its former glory. All of them have been generous to a fault.

For the past weeks, heroes have been painting, cleaning nonstop, and hanging Gilbert and Georges, led by the West Country-born Brixton-based interior designer Russell Sage, who has cajoled British craftsmen and artists from George Smith, The English Looking Glass, Based Upon, Coote & Co, Luke Irwin and Farrow & Ball to donate the paint, the furniture, art, lights and rugs on the floor. I was a liability with a paintbrush, although the railings and front door, the handiwork of my girlfriend Mary-Claire and me, I think you will agree, have scrubbed up nicely.

So, until Christmas, knock on the door of No 1 Greek Street and you will find a pop-up members' club called Quintessentially Soho, a not-for-profit enterprise with all proceeds going to the House of St Barnabas and our own Quintessentially Foundation.