Why is it called a Wikkelboat? The top of the boat is wrapped in 24 layers of corrugated cardboard, making the boat not only very light but also well insulated in terms of sound and temperature. Around it is a kind of raincoat and around it is a wooden covering layer. The underside is made of aluminum and this also includes the air conditioning and water drainage. The boat can sail, but this only happens occasionally so is not available to guests.