I have since improved this by putting another layer of ribbed rubber matting on the mattress level. I use either a double or single foam mattress depending on company and or extra gear. Can fit esky, clothes bag, food boxes, hurricane stove etc all up front of matress and can load heaps of extra gear next to single mattress. Best part is when a few of us go away the mattress comes out and we can stack about 5 more boards on their sides plus sails masts etc.
The whole level is removable as it is aluminium angle bolted to threads within the walls of the van so if you need to cart motorbike or similar it only takes ten minutes to get it out. The bearers for the wooden bed floor are alum square tubing which sit on the angle with the wood sitting inside the whole frame. The whole lot is secured by flat head bolts with wingnuts for quick removal
I decided to put my sails in the roof in basically upside down roof racks made from angle brackets and square alum tubing with pipe insulation around it. I think it makes best room of the "dead space" in the roof area.
With rubber matting on both levels which has a lip up the sides of about 200mm nearly all your sand and saltwater is caught. I let it dry then just brush it out with a dustpan brush.
Its a simple concept but works really well and was easy to put together with the ability to remove if you need too.
With the setup as shown I can fit three boards, two booms and 3 masts in the bottom section and up to seven sails in the roof space. I put the curtain in to keep the light out from the front end. When the rear door is down, due to tint on rear window and curtain it is near impossible to see in the back.
If you want any photos of the anchoring or framework just email us and Ill send them on.