High damp reading

On the annual damp reading checks carried out in July this year, we had a 40% reading under the lounge seating area - off side on a A-S Bourton.(2019 ) 

Investigation was carried out over the last couple of months in the area of the water fill point and pipework at the forward end of the storage area under the lounge seat, this showed no signs of leakage from the pipework.
I placed a small chemical dehumidifier by the pipe work, which showed some presence of water by absorption over a period of several weeks.

I am beginning to assume that this may be caused by bad ventilation, or lack of.

The forward vent is between the leisure battery  and the built in box for the water dump valve , water pressure switch and EC700 units to the rear of the storage area and not too far away from the two vents beneath the wardrobe.

Because the promised internal front screens didn’t appear until year 3 of our ownership we had modified and fitted two curtains to keep the warmth in the habitation area. 
The cab area turned out to be a real heat sink .

There are several questions that I need answered ,
1) The leisure  battery is fitted across the storage area , which  means the air ducting cannot pass by the battery and therefore no warmth or ventilation in the forward area of the storage area is available. Has this battery ever been moved to sit fore/ aft position?

2) There are no other vents in that storage area save for one in the floor that passes to outside the vehicle.
Are there other vents on the storage side panels that might not have been fitted ?

This also means any warm air is to the rear of the habitation area if you chose to sit in the rotated front seats.

The vehicle is due back into the dealership to examine the problem next week,  A-S showed little interest as such  but has left it to the dealership to examine the problem.

I don’t recall we had this problem with the Broadway which we had for over three years, before changing to the Bourton with the same layout being End Kitchen.15:15:21

I had a similar issue turned out to be outside skin fittings  barbecue point etc ..

Hi
    It may not be your year, but did not some models have leaks around the window surrounds?
      Alan

I had a similar issue earlier this year and I had also initially thought it was coming from the pipework.

But, as Alan (gemdeco) mentioned, it turned out to be seeping in through the front corner of the nearside window, as the seal had become squashed over time. The water then made its way down the wall behind the seat back, into the internal cupboard behind the gas cylinders, along the floor into the forward part of the loung.

On emptying the cupboard and removing the back panel, it become evident that this had been a long term issue, worsened by the recent heavy rain and being parked on a slope.

Solution : 
To clear any collected rubbish in the corner of the window.
To clean and treat the rubber seal.
To crack the window open for a while, so the rubber could regain original shape.
Dealer also fitted a small inconspicous 'channel' above the window, to divert water from the roof.

Result:
After drying out inside, this seems to have done the trick

Hope this helps your investigation 
....  lesson for me, check and maintain all the window seals !!!

I had a similar experience with medium damp readings under the offside lounge seating.

Using three different moisture meters, designed to detect and measure moisture at different depths, I found no evidence of any water/moisture ingress around the window, or any of the cut-outs through the foam cored side panel.

I spent a week or so monitoring the underside of the locker after heavy rain. I eventually found that water runs down the joint at the forward end of the side panel and exits on the inside, where it runs onto, along and across the plywood base of the locker.

The water then enters the end grain of the plywood at the forward end and along the outer edge, due to these areas not being adequately sealed. In addition, it enters the joints in the plywood, where gaps are visible.

I subsequently used a fan heater (with care, due to the adjacent gas tank!!) to dry out the plywood as thoroughly as possible. I then sealed all the edges and joints, where I could access them. To date, after six months, the moisture readings remain very low.

One might ask, why am I concerned about water running down from the joint causing water ingress, when this area will be very wet when driving in wet conditions? My answer is that of course water ingress will occur under both conditions, but rain water is running down even when the van isn't in use. Sealing the areas will obviously help in both conditions.

Of course, without dismantling, you cannot gain access to all the areas where water ingress into the plywood may occur, but my solution seems to have significantly reduced the water ingress. (If only Auto-Sleepers sealed the underside with a GRP skin, as some other manufacturers do, we would not be faced with this problem. Even better, stop using plywood in the construction!)

Although I carried out exhaustive tests, I never did find where the water enters the joint at the forward end of the panel. Perhaps another owner has the answer. 

As a precautionary measure, I also sealed the end grain and joints in the plywood under the nearside lounge seating.

I had a similar experience and the water was found to be coming in behind the gas filler point, I also had water leaking in behind the electric inlet socket, if you have a damp meter it would pay to check all the items fixed though the wall.

I also found water leaking in behind both frige vents, the barbecue gas point and the TV point on the other side of the van.

Good luck

Sparks wrote:I had a similar experience and the water was found to be coming in behind the gas filler point, I also had water leaking in behind the electric inlet socket, if you have a damp meter it would pay to check all the items fixed though the wall.

I also found water leaking in behind both frige vents, the barbecue gas point and the TV point on the other side of the van.

Good luck

Thank you Sparks.

Having read about various areas of water ingress reported by other owners, I have thoroughly checked every opening and fitting. Thankfully, to date, I have found no ingress.

I recall that Auto-Sleepers' changed the method of sealing the fittings, as a result of the leaks you describe. This new method so far appears to have been successful, at least on our Bourton.