With the soon arrival of our newborn, I have decided it's time to look at extending the sleeping arrangements in our van.
Currently, it only sleep two! It should sleep 3 but the 'hammock' is knackered.
What I would like to do is convert the upper storage unit in to a bed area.

I know it's going to need extending, for sleeping purposes. What I am interested to know is, what kind of materials do I need to get to make the base extensions, firm for climbing up on. Also, how to store those parts!
Cheers in advance!