2004 Symbol - Damp in over-cab locker

Hi, I'm new to the forum and new to campervanning (though have had a caravan before). I have a 2004 Symbol, bought just three months ago, and have a damp problem in the over-cab locker - it manifests itself as damp/wet patches along the join line where the main roof lining meets the front roof lining (inside the locker). It usually dries out after about a day.

However, this doesn't appear when the van is just parked-up, un-used (no matter how wet the weather is), it only appears during, or after, being driven or stayed in.  So I have the old dilemma, is this a leak or condensation?

I've checked the most likely suspect, the Heki, and it looks like it has been recently re-sealed - indeed, I have added more Sikaflex along the front edge. I've also popped out the interior cab light and looked behind it - all clean and dry.

I'd like to remove the front roof lining (and maybe even the locker door bulkhead to lower the front of the main roof lining), so that I can have a good look. My question is; is this possible?  If so, how do I go about it?

If anyone out there has done this; is it easy, risky, foolhardy, or even pointless?

Any advice greatly welcomed.

(Or, can anyone recommend a knowledgeable repairer in the Cambridgeshire area).

Thanks
Alan

Our 2009 Symbol had a similar issue, and very occasionally we get it in the Kemerton over-cab space.  Both vans are different in construction from each other and differ from your Symbol, so my comments need to be read in that context but the cause in our cases was definitely condensation.  

I put it down to two factors: firstly, the front-facing roof section above the windscreen experiences a lower temperature than any other section of bodywork due to windchill when underway; secondly, we stuff bedding into the space above the cab, so air doesn't circulate much and creates pockets of trapped moisture within the space.  Both factors combine to provide the conditions for condensation. Fortunately in the Kemerton it's a rare occurrence and only ever when the outside temperature is near or below 0C.

My advice would be to monitor the situation once the warmer spring weather arrives.  If your interior cab light is dry, as you state, then that strikes me as a good sign.  If you had a leak I think I'd expect that to show obvious signs of ingress, as it's possible the lowest part of the overcab area.

Tim

Prior to my later model Boxer I had a 2006 Tribby  on the same van as yours which suffered the same damp patches in the over the cab locker. It was condensation due to the poor insulation on the van in this area.
Being a cheap skate I used stick on carpet tiles from the pound shop over the bare metal found which was causing the condensation, never had any more problems.

I did take the wooden front off but cannot remember much about how sorry

David

Thanks both for your help. Condensation was my gut feeling but as a newbie, wanted some advice from those more experienced than me.

Just wondering now whether its a DIY job or one for an expert?

Alan