my caravan floor is spongy in sevral places and needs working on but i dont have a clue how. also an exterior panel has been pulled out and have found that the timber framework has all rotted so also need to know how to fix this problem
With difficulty try local caravan spares shop for a kit to re-laminate the floor as it sounds like the floor has de-laminated in parts ie: the sandwich floor is parting Think ice cream between two wafers that's your floor with part pulling away from polystyrene insulation.
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix caravans/motorhomes.