Winter issue!

[Phantom]

When our motorhome was not used during the last two winters there were no issues. But full-timing in it this winter in the UK has caused/shown a few problems which I have remedied all but one which I hadn't figured out until quite by accident today. Under a bench seat the end of a small timber seemed to be constantly wet where it met the floor!
Today I decided to fit a shelf in a high wall cupboard just behind the cab, and out of curiosity removed the top back panel just to see what wiring was behind it. It showed where the front fibreglass canopy meets the insulated main body, but the thin black foam stuck to canopy side was wet and mouldy. The area is about a foot square and was poorly insulated causing condensation which wicked down another foam strip and dripped down unseen behind the panel behind the cab onto the floor where it passed under the panel and was then wicked up by the bare timber strip.
So I cut out the offending foam panel, cleaned and dried the area well by using a small fan heater and then applied a sheet of adhesive backed 10mm closed cell foam. The opposite cupboard as expected was just about as bad so I did the same there too.
It just seems strange that some manufacturers have used inadequately thin water absorbant open cell foam as insulation in a few places, causing condensation which it absorbs making it even less efficient. I've learnt a lot more about motorhomes this winter!

 

[Martin P]

When I fitted a new boiler to our MH last year I had to remove the plastic overcab linings to run new cabling and found the same lack of insulation to the fibreglass moulding. Remedied now and the van stays noticably warmer

 

[Phantom]

The cab roof is insulated fine as is the main body, just that relatively small side patch inbetween which is a weak point. You may assume that it's all good, but you'll never quite know until you check for yourself!