Called the Onion Shed because until the early 1980's it was used by a group of Breton Onion sellers. You used to see them cycling round south London with their bicycles heavily laden with strings of onions and garlic. A user posted that if they missed them in the street they would call round and buy onions from the shed, where they would be stringing then together. It was suspected the Bretons slept in the loft, although it was all fairly derelict. Subsequently it might have been home to the Onion Shed Theatre, a "small fringe theatre in Lambeth."
Who knew? !!

- Lothian and Ackerman