I just bought a 1993 Sprite Alpine 4, and guess what - it has damp in the rear lower corner.
Today I've stripped all the rotten wallboards and wooden battens from the back of the van and so far so good.
Still not sure if the damp is getting in. It could be:
1. from the window seal (looks unlikely),
2. the awning rail (partly removed and drying, battens on corner of van are sodden from half way down),
3. the lighting board (removed, damp inside, but generally solid), or
4. the grab handles - and thats my problem...
The wood inside the van that the handles connect to have clearly been damp in the past, but I can't for the life of me work out how to remove them from the van.
The handles appear to be in 2 sections, but a can't separate them without potentially cracking the plastic.
Any ideas on how these come off? It's driving me insane.
You may find plastic screws inside caravan, ie they bolt all the way through. If you start trying to lever off plastic of that age it will probably break so best bet is just to seal around outside of handles with PU sealant, that what I did with mine. With an old caravan its mainly about what works rather that what looks good.
You are quite right about grab handles, a common point of water ingress that often gets overlooked.