Locating source of damp

[Threehorsehead]

We have a 2002 Abbey Freestyle 500SE. My damp meter is showing damp in the near side rear corner of the wall, for about 100mm the bottom, and to a lesser extent the floor.

The wall is dry further up.

I’m trying to work out where the most likely point of entry is.

1) The 100mm seems to align well with the awning rail. From the outside the rail appears solid.

2) I also wondered about the rear light cluster but the rear wall is dry around the location of the light

3) or perhaps the vertical seam between the wall and rear panel but it’s dry further up as well.

If you had to pick, where would you choose?

Thanks and regards

Phil

 

[borderbilly]

When you say showing damp, what are the readings?

 

[birdman101]

Grab handles are a common leaking point. Or the awning rail running down the corner.It should not be the light cluster as that is mounted in an external moulding fitted onto the Aluminium back panel.

 

[audiorob]

Might be worth removing the herzim strip about half meter on that corner rail and checking that the screws are not loose or overly rusty. Worth replacing with stainless steel and sealing with mastic. Belt and braces to reseal that section of rail while you are at work in the vicinity. I use a plastic artists acrylic paint spatula to encourage the strip back in - slot in one edge and run the spatula down the opposite edge - saves herzim thumb that was subject if a recent thread!

 

[Threehorsehead]

Readings along the bottom are between 25-50%

 

[ProfJohnL]

Frankly non of our guesses are going to give any confidence of the source of your leak. You have to bite the bullet and whoever does the work needs to use a structured approach to expose the affected area and trace the evidence back to it's source.

 

[IanB1485]

The most probable cause is that the rear wall has had water running down the outside, and this has wet the rear wooden member and the water has 'wicked' through it to the rear floor framing piece and the inner plywood wallboard and upwards by capillary action . I have dealt with several caravans with this issue . The way I have tackled is from underneath , removing the rear corner steady , often having to grind off the rear nut. then using a multitool, cut out the soft areas until good wood is reached, then fit new frame members attaching them to the good wood with Soudal P45 polyurethane adhesive and also fit 23mm thick x 100mm wide marine grade plywood along the rear.This is approximately what the original rear piece of the floor is made of.
I also pretreat all replacement pieces with Thompsons water seal. you can replace the wallboard with 3.6mm plywood and vinyl wallpaper of your choice , I use spray contact adhesive to attach the wallpaper which I get from Park and leisure Ltd. . Once all repairs are done , I coat the underside of the floor with car body underseal. and separate the rear panel lip from the floor to prevent water wicking from the rear wall to floor framing .