We manufacture a Westdubs pop top self elevating beds to pop up out of the way when using the inside of the camper. Then when night time comes pull it down for extra sleeping.
Even if you haven't got any extra folk to sleep in the van with you. people don't believe how much noise is cut out from outside by having it down.
The mattress is covered in grey waterproof canvas this stops the nightmare that spilt drinks create at night. Know one wants to sleep on a wet bed. but more importantly you wouldn't want anything dripping on you in the middle of the night either. Plus the mattress is great for using outside for picnics too.