Cardboard boat sails on the Thames

Who would go afloat on a boat made of cardboard? Surely these craft would float only on the imaginary ocean that spreads across the living room floor?

But Kevin McCloud made a fully working houseboat and sailed it down the Thames to highlight what can be done with the mountain of stuff we throw away each day.

Apparently the aim is to cross the English Channel in it next year.

All images from Grand Designs via The Independent and there's also videos about it here (complete with cardboard remote controlled boat) and here.