I have a 30& damp reading in shower walls.
Is this an easy DIY fix or a job for the workshop?
My caravan service guy is going to overseal the outside I don't trust myself not make a hash of that job, not the best mastic guy.
Also if it is a diy job, would you replace the ply with wetwall or ply?
Thinking wetwall might be a tad too thick.
firstly is your service guy doing it as a temp fix? because oversealing is just that, temporary. yes its a diy job if you have the space, you need to stop the water getting in first of all, so removal of the trims, total clean and then replace with fresh silkoflex, then there is the issue of is the wood batens ok? or is it rotten and needs replacing/reframing.
If its in the shower, and it doesnt smell or has mould, i would personally leave it. Its the shower at the end of the day. Theres water in there anyway. Weighing the upheaval and cost against what the van must be worth - 2k? I'd just continue to enjoy it, myself.
You need to find out where the moisture is coming from. Is it ingress from outside or is it a leaking shower tray and surrounding fixtures like tap connections.
I have recently bought an Elldis 2 berth that looked ok inside the shower but smelt a bit musty. On closer inspection I found that the white sealant hadn't really been applied very well and water was seeping past and soaking the floor under the tray.
I've ended up ripping the whole lot out and found other leaks like lose hose connections under the mixer taps and no sealant where the mixer tap panel meets the wall. Every time someone took a shower or washed in the basin it also was washing the floor of the van.
This is a bit over-kill for most but I've bought two 8x4 sheets of 2.5mm white plastic and created a complete wet-room. Took a while but no more leaks.
If its from the outside then the trims need to come off to be re-sealed. Also check the seals around any windows. If there's one in the shower room its quite small and only takes 15 mins to re-seal. £5 tube from Halfrods. Good luck with it.