Aha, found it!

I suspected that water had been finding its way in around/through the plastic moulding that holds the rear lights and number plate.  There were a few obvious cracks and the plastic looked aged and brittle.  On removal it became clear that I was right to suspect it.

Removing the moulding meant taking off two sections of awning rail as well as the moulding itself as it wraps around the caravan edges slightly.  Fortunately the awning rail  is made up of several sections so I only had to remove a five foot section on each side.  This meant I could also further inspect how well the rail itself was sealed.  Pulling out the infill strip from the aluminium rail showed all the screw heads were well rusted, some gone completely.  None of them came out without any work!  Cutting a slot in the head with a cutting disc in a cheap Dremel knock off worked for a few, allowing me to use a flat bladed screwdriver.  This only worked on screws that still had a head, others had to wait until the rail was off, then I could use mole grips on what was left and unscrew them that way.

Removing the moulding was the same story of very rusty screws that I dealt with in the same way plus some staples, again very rusty.  Once it was off I could see where a lot of water had been getting in.  Under the top inside edge of the moulding was a wooden baton that was intended to give some support to the moulding.  This had been screwed to the caravan skin only, there was nothing inside for the screws to bite in to!!!  It was the same with the screws holding the moulding on, only screwed in to the skin.  How it was meant to stay firmly fixed I don't know.  The skin is under 1mm thick, no way screws will hold firm in that.  Once water had got in it had rusted the screws allowing more water in.

The batten was sodden and rotten at one end and it just pulled off easily offering no resistance at all.

Mmm, how was I going to deal with this?  I now had an awful lot of holes to deal with.

Simon.

Still chasing the damp...

So, it seemed that I had water coming in from the left, the right and along the back wall.  This had caused some timbers to rot, some had even turned to mush it was that bad.  In the corners the floor was also very wet and soft in places.  I now have a section of awning rail off on each side at the back as I suspect that at least some of the water is coming in there so I now have to cover it up with a tarp.

In order to trace the sources I have had to remove a fair bit of wall board and some good timber.  I wanted to chase it back to good dry wood before putting in any new.  In the left corner this meant removing the bottom frame timber for the toilet hatch as well as a timber in the base of the wall.  Around two feet of vertical framework has come out from both the side and rear walls.  It's a similar story on the right hand side too.  Fortunately all the wall board I have removed is unseen so I can just replace it with plain ply, much cheaper!

After removing the rotten timber I started digging around on the floor with a wood chisel to see what state it was in, quite bad was the answer!  In this picture there is already a new part of framework for the toilet hatch as I wanted to make sure it was sealed while I worked elsewhere.

So I decided that I needed to cut out a corner of the top piece of the floor sandwich so I could replace it with some new 6mm marine ply.  Only the ply was rotten with the timbers underneath being wet but firm.  After cutting back it looked like this.

I left it like that to dry for a few days then cut a patch from some marine ply and glued and screwed it in place using the PU glue I had bought for the aborted floor delamination repair.

It was the same story with the right hand corner.  Cut it back to good firm ply then glue and screw a patch.

I then set about making some replacement framework and finding out where the water was entering along the back wall.  More next time.

Simon.

Previous owners....

Previous owners, do not under any circumstances over estimate their abilities!  Check everything.

While I was digesting what I had found inside the caravan I decided that in time I would reseal anything that was mounted on the outside and looked easy to do.  I started by looking at the fridge vents.

Notice anything wrong with the bottom vent here?

I didn't until I started looking at the top vent, wondering how difficult it would be to remove as there is the gas burner flue integrated in to it.

It turns out you can just lift out the small part on the end and remove the metal ducting, then unscrew the vent just like the lower one. Easy.  Notice the difference in the grills yet?  The lower vent (top pic) is upside down!  This means that any water hitting the vent is directed inside the caravan as when fitted this way the slats slope down into the caravan.  An easy mistake to make, possibly?

I removed both vents so I could clean them up and reseal them.  On removal I discovered that there was next to no mastic at all, only remnants of what had once been there.  I'm guessing someone has had both vents off to look at the back of the fridge at some point and had no mastic so just put them on and hoped for the best.  Either that or they didn't care!

Fortunately it appeared that not too much water had found its way in and although the inner walls were a little damp they weren't rotten.  I refitted the vents using mastic tape and they now both look like this, also the bottom vent is now the right way up.

I'm glad I decided to check them when I did or it might have led to more rot inside.  Hopefully everything will now dry out behind the fridge and no more water will get in.

Simon.

Just how far does the rot go?

Removing the kitchen and toilet showed I had a pretty serious damp problem.  This had caused the plywood wall boards along the back edge to rot and turn into pulp in several places.  Just how bad could this be?  In order to find out I had to remove wall board to expose the caravans skeleton.  A scary proposition I thought.  I wasn't familiar with how a caravan was constructed at this time, but I know a lot more now!

Removing the wall board was a feat in itself.  Like the floor the wall is a sandwich of three layers, all bonded together.  Where the board was totally rotten I could quite easily remove most of it with a wall paper scraper  leaving a dirty brown mess behind.  I guess that is all that is left of the inner face of the ply.  Removing the still good parts of board was a little harder, but it does come off a lot cleaner if you do it right.  As it is bonded you can't just rip it off, not without damaging the polystyrene.  My searching on the 'net had found someone recommending the use of an 'oscillating multi tool' for the job.  Despite being reasonably clued up on DIY I'd never come across one of these so I did some more research.  It did indeed look like the tool for the job. The idea is to cut the wall board inner ply into sections and remove each section in turn using a wall paper scraper.

Argos had the Stanley Fatmax tool for sale at a reduced price and I had some Nectar points to use so off I went.  What an amazing piece of kit!  It comes with various blades all packed in a very tough carry case and has been invaluable in the whole strip down and rebuild process.  If you don't have one then get one now!

Here you can see what I mean about cutting the board in to sections before removal.  The multitool comes with a semicircle blade that you can use to just cut through the inner board.  You then insert the scraper keeping it a flat as possible and wiggle and push it between the board and the polystyrene taking each square of in turn.  Time consuming but it leaves most of the polystyrene intact.

I also removed some board on both side walls chasing the damp to see where it was coming from.  So far I suspected the awning rails both side, possibly one handle and with a very strong suspicion that something was wrong behind the plastic moulding that carries the lights and number plate on the rear of the 'van.

In the left corner (as you face the back from inside) near the toilet hatch there was rotten timber.  The horizontal frame piece under the toilet door, the horizontal piece in contact with the floor, the floor itself, the piece at 45 degrees and the vertical pieces were all rotten.

On the right hand side it was a similar story.  Damp had moved along from the back and started soaking along the bottom timbers.  The 45 degree piece was just mush, as was a lot of the vertical piece.

At this point I was starting to think this may all be getting a bit much for me to cope with.  Time to go home, pour myself a Whisky and look at the pictures I'd taken, then I needed to try and come up with some sort of plan.

Simon.

Oh dear, I have a lot of damp!

Over the Christmas holidays I planned to take advantage of time off work to fix the caravan floor.  There are two areas that are suffering delamination.  One by the kitchen the other near the fridge.  A caravans floor is made up of a sandwich of polystyrene between two sheets of plywood.  All of this is bonded together to make a very strong but light structure.  Over time frequently used areas of the floor can suffer when the bond breaks down and the plywood is free to move up and down when you walk on it.  This then starts to damage the polystyrene and it spirals downhill.

So I moved the caravan from storage to the inlaws drive to start repairs.  This however got interrupted by me finding a damp carpet next to the kitchen the following morning.  This had happened only once before, both times after exceptionally heavy rain.  The first time I put it down to me not shutting the caravan door properly.  It would turn out I was very wrong!

I put the floor repairs on hold to investigate where the water might have been coming in.  Inside both kitchen cupboards the floor was wet.  Mmm, maybe the source is somewhere in there.  A little look in the right hand one showed this.

In the cupboard to the left I found this.

I had a big problem!  There and then I decided I would need to remove the kitchen to expose the full extent of the damp.  How far would it go?  Getting the kitchen out was not as easy as it sounds, due to rusty or hidden screws but it did come out in the end.  Pulling off some wall paper a little digging showed me that the damp was quite extensive and looking like it was the full width of the back wall.  It wasn't clear at this point where the water had been coming in but one of the handles looked to be a possible source, as well as the awning rail.

Out next was the toilet and toilet wall.  Yep you guessed it, lots of damp there too!

A little worried by what I found I decided it was time to go home and consult the Internet for advice.  That is where I found the 'Fixed it' club on UK Campsite, a fantastic source of advice and inspiration.  It seemed all was not lost, it was repairable.

Simon

Leaky Carver Cascade 2

Next thing on the list was the Carver Cascade.  After testing the water heater, both on gas and electric I found the bottom of the polystyrene to be a little damp.  Obviously water was getting out from somewhere and after removing all the polystyrene insulation and the element cover I found the source.

Behind that white oval shaped cover is the main powered heating element, the gas burner is at the other end.  The element is held in by two nuts/bolts with an o-ring sealing the joint.  I suspected that the joint just needed nipping up and that would be that.  I was wrong.  If you have ever stripped a thread or broken a bolt then you will know the feeling I got when I tried to nip up the nuts.  One of them just turned and turned, oh dear...

So I drained the system down and removed the cylinder from the heater.  It seems that the bolt head that has been immersed in water for who knows how long has been slowly dissolving over the years.  One head was missing completely and the other was well on its way.

Looking on Ebay I came to realise this must be a fairly common thing as seal kits were readily available.  The kit I ordered came with two replacement nuts and bolts, o-ring seals for the cylinder, bolts and element. 

Easy to fit and I now have a leak free water heater.

Simon

A new roof light.

I mentioned in my previous post that our Musketeer needed a new roof light.  UV appeared to have aged the plastic and the translucent part had cracked.  An attempt to repair it with some sort of mastic or sealant had been made, but it wasn't working and a some water was coming in when it rained.  After getting the old one off this is what I saw.

The lugs where the screws that hold the cover on to the handles had broken away and some sort of sealant had been put in to try and fix it.  I doubt it ever sealed it, but it did look to have been there for some time.  A replacement unit was only £40 so why didn't the previous owner just replace it?  Someone had already replaced the toilet one in the not too distant past.
  With the old roof light out I started to clean up the hole that was left and inspect the timbers.  Thankfully it had not been leaking there and everything was in good order.

I fixed in the new roof light using fresh mastic tape.  All in all a very easy and satisfying job to do.

That roof could do with a clean!

Simon.