Damp / water damage / repair

wonderworm

Just read your post Peasant about damp underneath a camper van. Do you have any idea how difficult it is to fix the "turf" problem underneath a van or how much work is involved? Who would you get to do it?

peasant

Hi wonderworm

Welcome to the forum. As you can see, I've created a new thread for your question, as it might get lost in the other one. Hope that is ok.

So far, I'm just an "expert" at finding damp/rotten patches, not at fixing them.

The only way of fixing such damage properly, is to rip out whatever is affected and replace with new wood.

I'm not currently aware of anyone (be it carpenter or motorhome dealer) who specialises in that sort of repair.

With the number of motorhomes about now, I'm expecting this to become a fairly common problem and am hoping that someone out there knows someone who does a good job on that.

wonderworm

makes more sense to make it a new thread thx.

*Kol*

So how would I recognise a damp/rotten patch if there is no visible staining/damp patch? I'll be looking tomorrow!!

peasant wrote: »

Hi wonderworm

Welcome to the forum. As you can see, I've created a new thread for your question, as it might get lost in the other one. Hope that is ok.

So far, I'm just an "expert" at finding damp/rotten patches, not at fixing them.

The only way of fixing such damage properly, is to rip out whatever is affected and replace with new wood.

I'm not currently aware of anyone (be it carpenter or motorhome dealer) who specialises in that sort of repair.

With the number of motorhomes about now, I'm expecting this to become a fairly common problem and am hoping that someone out there knows someone who does a good job on that.

peasant

Other than with a professional instrument for measuring damp, you'll have to go by the rule of thumb.

In other words, stick your fingers in as many nooks and crannys as you can possibly find (especially around and near edges) and apply pressure to walls and floors

If it gives, it's dodgy

*Kol*

Thx. I have noticed that the outer skin of the motorhome "gives" around the curved areas on the outside. i.e. if you press on the outer skin there is a gap between it and whatever is inside? I sthis normal or is the outer skin supposed to be bonded whatever is inside?

Another thing i noticed this morning after a night of heavy rain is that water is pooling on the roof just behind the alcove. Is this something I should be worried about? I'll post a pic to show how much water there is.

peasant

Question one:
Depends on the construction underneath. If you're pressing where there is no wooden frame but only insulation, of course that would "give" a bit. I'm not quite sure where exactly you're talking about.

But the pressure test only really makes sense on the inside, because squeezing around on the sheet metal doesn't really tell you much as it is rather a loose fit (mostly glued on) and has to be as it contracts and expands with heat/cold

Question two:
Due to the design of the roofline, the spot below the hump of the alcove is an area where water will always collect (unless your parked facing up a steep hill). So that is normal.
What's critical is that none of that water dissapears through the seams at the edge or any rooflights that may be there. Have a look on the roof where the water sits and then check the appropriate seam aereas from the inside for signs of damp.


This whole damp/rot business is a bit tricky, because water moves in 'mysterious ways'.
For example, water could run inside the side wall from your little lake near the hump and run down the construction without doing much damage or leaving much of a trace. It could trickle straight down or take a sideways turn without you knowing. Only when it hits an obstacle where it can flow no more (window sill, service hatch, floor beam) will it sit there and soak into the structure and do damage over time.

*Kol*

This is what I'm talking about in the photos. I can't find anything inside which is good I guess. I will check to see if the water stays there as I dont plan to move the motorhome today. In front of the puddles there is give in the sheetmetal (could be to do with the slope and curve in that area?)..theres also give at the very back where the sheetmetal curves from the roof to the back of the motorhome (could be the same reason as above?). Either way what is underneath seem fairly solid on the roof and sides (like sheets of plywood?).

peasant

Yes, it's ok for the curvy bits to have bit of give. This allows for expansion or contraction in the heat/cold. You're looking at a good square footage of sheet metal there that has quite some movement in it.

Your puddles are nothing to worry about really (drainage would be difficult) as long as the seals on the seams left and right and on the fixings of the roofrail are still good and not letting in water.

Should you buy that camper, re-doing the seals as a precaution (when it's warm and dry outside) might be a good idea at some stage.


Other critical aereas to check (from the inside) are where stuff has been bolted onto the body (antennas, cameras, bike carriers, etc) as every hole is a possible leak if it's not properly sealed.

Also inside cupboards / wardrobes, particularly at the bottom and around window frames and chimneys, hatches, sockets.

Also creep under the yoke and try to inspect behind the plastic skirting

stapeler

Watch out for blistering or bubbling of inside surfaces which is a giveaway. Where timbers get wet they swell and cause some bulging. A damp detector can be picked up quiet cheeply on Ebay and gives a good indication. Lidl/Aldi recently had damp detectors for about a tenner that are adequate.
Damp will travel thoughout the vehicle so you wont necessarly see damp where you might expect to see it. Around windows, roof/bike racks etc can be a problem.
I like to park my motorhome on a slight incline when not in use which allows rainwater to run off and prevents puddles on top.

peasant

Ok, I've done a little homework and scrounged some pictures from a German motorhome forum (with permission, of course)

This poor chap discovered a damp patch near his shower basin one day and started to investigate. He found more and ended up ripping out the entire bathrom and toilet to find a rotten rear wall and floor on his vehicle.



The pictures show the rotten rear after removal of all the furniture, the rear after removal of most of the rotten plywood, uncovering rotten beams as well and the replacement of those beams with new ones as well as a new section of floor.

Here's the slideshow:
http://img99.imageshack.us/slideshow/player.php?id=img99/8329/1193774148thg.smil

This poor chap did this all by himself and without prior experience.
So, it can be done ...but easy it aint

The 'culprits' for this damage were several: a leaking hatch (the one on the pics) and several leaking boltholes from a roofladder and a bike rack.

The forum with whose kind permission I've nicked the pics is this:
http://www.wohnmobilforum.de/

and the actual thread about this repair is this:
http://www.wohnmobilforum.de/w-t12232,highlight,feuchtbiotop.html
(you'd need to log in to see the pics)

*Kol*

Now I'm feeling paranoid!! :eek: The gas locker door on the motorhome that I'm looking at is like a sponge. I'll have to have a good look in that area.