Hi Bob,
Firstly welcome to a great forum - I trust you time here will be one of sharing good experiences with other like minded people.
Not all the advice given can be favourable to your thoughts, most of us offer advice that will benefit you in the long term.
I hope I'm not jumping into Possum's barrow but he often suggests to look in the Caravan Council's website. You can find it by "Searching" the forum chapters or just checking posts either in the General or Techies chapters.
Bear in mind that water leaks in timber framed vans can be "not so good", but several major manufacturers are still using timber (eg meranti, from the rain forests of Indonesia) for their on & off road vans.
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Warren
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If you don't get it done today, there's always tomorrow!