Kevin was invited by Birmingham City University to propose his own Grrreen Shed by colouring in a cardboard shed template (designed by me for the event). Then, along with 7 other sheds I converted it into reality using a standard Forest Garden 6' x 4' x 6'4" shiplap shed.
It formed a backdrop to the whole feature (more info at bcu.ac.uk/green). It took me 20 hours to paint, but it was worth it (I think!)