Over wintering caravan - suggestions please.

[Sam Vimes]

When we had the vans first service a couple of weeks back and they found damp in places - its only 12mths old- it got me thinking about what to do over winter.

It sits outside exposed to the elements and a full cover is impractical, although not sure this would make much difference in respect of damp. When we had a full cover on our Motorhome it got shredded in no time at all in the high winds.

What we've done so far is to open as many cupboards as possible and pull all the seat and back cushions away from the walls to allow for better air circulation.

We've put a couple of damp boxes inside but I'm not convinced these do much. Might also consider firing up the heater once a month for a reasonable time - not a bad place to have a coffee and some cake while its warming up

Any other suggestions would be gratefully received.

 

[Jcloughie]

I don’t believe that moisture absorbers can do anything at all. Just a waste of money. Would only work in an unventilated area. I also don’t think putting the heating on would do anything. In fact it may have a detrimental affect as when you warm it up it will attract moisture into the air in the van. Then you let it cool down again and it condenses.

Some argue for and against covers, But if it’s impractical then that’s not an option. The best thing for damp is to trace it and cure the cause. Much easier said than done.

Not a cheap option. But is is possible to set up a screen, or car port affair. It would offer shelter and protection.

John

 

[otherclive]

Agree with JC’s post. I’ve always done what you suggest such that the inside of the van is totally opened up, with upholstery spread everywhere, tended to look like an explosion in a furniture store. Make sure work surfaces and hard surfaces do not have something called Sheen or Pledge on them.. My wife tells me they are polishes. But they would attract mildew or mould.

 

[Sam Vimes]

Thanks for your replies.

The current damp will be fixed under warranty and we're just waiting for the dealer to get the parts. However, while further damp problems in the structure may not occur in the future the possibility of damp/mould being present internally could still be a problem and its this I want to minimise.

Good air circulation is one aspect that I can do something about easily and yes it currently looks like its been vandalised.

It sits in a car port and I've often wondered about enclosing that but it would have to be air tight in order to combat the high humidity we get in the winter months - its currently 95%. My large shed which is adjacent to the van gets damp so I can't store things like tools in there. Even paper gets a bit soggy after a while.

Vans by design leak air - more than I think they should. I'm sure they could be designed so that don't need so many vent points in them.

Maybe we should tow it somewhere warmer and drier in the winter but I'm not quite ready for trips abroad in it yet.

 

[Jcloughie]

Thanks for your replies.

The current damp will be fixed under warranty and we're just waiting for the dealer to get the parts. However, while further damp problems in the structure may not occur in the future the possibility of damp/mould being present internally could still be a problem and its this I want to minimise.

Good air circulation is one aspect that I can do something about easily and yes it currently looks like its been vandalised.

It sits in a car port and I've often wondered about enclosing that but it would have to be air tight in order to combat the high humidity we get in the winter months - its currently 95%. My large shed which is adjacent to the van gets damp so I can't store things like tools in there. Even paper gets a bit soggy after a while.

Vans by design leak air - more than I think they should. I'm sure they could be designed so that don't need so many vent points in them.

Maybe we should tow it somewhere warmer and drier in the winter but I'm not quite ready for trips abroad in it yet.

I think you have hit the nail on the head with the high winter humidity. Perhaps you could temporally block all ventilation and put a dehumidifier in on a timer. Drastic time need drastic measures!

John

 

[Bard Rooney]

We take all mattresses and cushions out, cupboards and drawers open, heat on at least once a week ( I agree that it’s lovely to take a cuppa and a book out when it’s on ) and we do put those moisture catchers in, you’d be surprised how much liquid they collect !! ( And yes our caravan is damp free ) . We don’t put a cover on ours though.

 

[DaveA1]

I don't think moister catchers (or whatever they are called) do any good, I can't help thinking because vans are well ventilated, all they do is draw damp in from the outside.
Sealing the van could course all sorts of problems. ie dry rot is through poor ventilation, it wont get that bad, of course, just an example. IT would certainly encourage black mould.
Ventilation, I'm sure is the best. There is not much water about on a cold sunny day, braising as far as Seggy is concerned. .
I have two opposing windows on the night latch, most of the time, rotating.

Serviced last weekend, dry as a bone.

 

[Beachball]

We take all mattresses and cushions out, cupboards and drawers open, heat on at least once a week ( I agree that it’s lovely to take a cuppa and a book out when it’s on ) and we do put those moisture catchers in, you’d be surprised how much liquid they collect !! ( And yes our caravan is damp free ) . We don’t put a cover on ours though.

We also use moisture catchers been using them for the past 31 years and our caravan is damp free so far

 

[DaveA1]

We also use moisture catchers been using them for the past 31 years and our caravan is damp free so far

Just means you have a good well serviced van.👍👍👍 19 years damp free never used a MC. Had a damp Baily but that was a spilt panel, 20 years ago, MC would not have prevented that. Condensation is not damp, as in the potential to distroy the fabric of the van, easily cleared.

 

[Beachball]

Our caravan is empty through the winter period and we put a breathable cover on and MC and we open all the cupboards , fridge door and wardrobe door and it your choice if you don"t want them in .

 

[Mel]

I was under the impression that “Damp” as in “the Dreaded Damp“ was about water ingress through the skin of the caravan, either through improper or damaged seals or where there were splits, cracks or breaks in outer walls.
Surface condensation and moisture due to weather conditions, whilst definitely “damp” to the touch and having the possibility to cause some mold growth; did not have the same structural rotting effect as water ingress.
Perhaps I have misunderstood?
If I haven’t misunderstood then to avoid condensation you need ventilation on a dry day, Open windows, cupboards open, gaps behind cushions. Put the heating on if you want, to move the air about, but with ventilation, otherwise you just add warm air, which contains more moisture than cold. The water ingress needs the source of the ingress resealing or repairing and is a different matter.
Hope the parts arrive soon. Ours took ages.

mel

 

[Buckman]

Moisture traps or absorbers are a total waste of time and money as all you are doing is trying dry out the atmosphere. You might as well set them up around the caravan for all the good that they will do. One of the biggest con jobs going around! LOL!

 

[DaveA1]

I was under the impression that “Damp” as in “the Dreaded Damp“ was about water ingress through the skin of the caravan, either through improper or damaged seals or where there were splits, cracks or breaks in outer walls.
Surface condensation and moisture due to weather conditions, whilst definitely “damp” to the touch and having the possibility to cause some mold growth; did not have the same structural rotting effect as water ingress.
Perhaps I have misunderstood?
If I haven’t misunderstood then to avoid condensation you need ventilation on a dry day, Open windows, cupboards open, gaps behind cushions. Put the heating on if you want, to move the air about, but with ventilation, otherwise you just add warm air, which contains more moisture than cold. The water ingress needs the source of the ingress resealing or repairing and is a different matter.
Hope the parts arrive soon. Ours took ages.

mel

Agree with you on all counts Mel. That's what I said in Post #9 You have a better grasp of detail, than me.
Ventilation Ventilation Ventilation.

 

[Beachball]

Moisture traps or absorbers are a total waste of time and money as all you are doing is trying dry out the atmosphere. You might as well set them up around the caravan for all the good that they will do. One of the biggest con jobs going around! LOL!

Well that your choice but I owned a 13 year old caravan that is damp free and I will continue to use them

 

[Challenger]

Agree with JC’s post. I’ve always done what you suggest such that the inside of the van is totally opened up, with upholstery spread everywhere, tended to look like an explosion in a furniture store. Make sure work surfaces and hard surfaces do not have something called Sheen or Pledge on them.. My wife tells me they are polishes. But they would attract mildew or mould.

Is there evidence for this claim ? I can find none on line .

 

[DaveA1]

Well that your choice but I owned a 13 year old caravan that is damp free and I will continue to use them

Thats great, My Corniche was in its 16th year, completely damp free. never used an MC The only reason I sold was that some window seemed it implode and some seemed on the point of exploding.

 

[Hutch]

Is there evidence for this claim ? I can find none on line .

My wife used to wipe down the "wooden" surfaces with Mr Sheen, and we noticed during the winter months between taking the van out, maybe every 6 weeks, we would have a light, smear of greenish mould in areas, stopped wipeing down in the winter and the green marks did not appear.

 

[Raywood]

I assume you have reported the problem to the dealer and they have put in a guarantee claim. Probably what you have to do now is wait and see what the maker says.
If there are problems then be aware of your legal rights for a repair which are mainly against the dealer. The regulations are covered in this months magazine which may be worth getting for these.
If you used a credit card for any part of the purchase, usually the deposit, or HP for the purchase then you also have rights against the finance companies involved.
If there is a problem let us know and you will get further help on here.
Not sure there is anything useful you can do if you cannot get it under shelter unless you run to the expense of a cover. As the others say the crystals ae never going to work.

 

[ProfJohnL]

Thanks for your replies.

The current damp will be fixed under warranty and we're just waiting for the dealer to get the parts. However, while further damp problems in the structure may not occur in the future the possibility of damp/mould being present internally could still be a problem and its this I want to minimise.

Good air circulation is one aspect that I can do something about easily and yes it currently looks like its been vandalised.

It sits in a car port and I've often wondered about enclosing that but it would have to be air tight in order to combat the high humidity we get in the winter months - its currently 95%. My large shed which is adjacent to the van gets damp so I can't store things like tools in there. Even paper gets a bit soggy after a while.

Vans by design leak air - more than I think they should. I'm sure they could be designed so that don't need so many vent points in them.

Maybe we should tow it somewhere warmer and drier in the winter but I'm not quite ready for trips abroad in it yet.

Hello Sam,

If you do have a water ingress problem, that must be resolved as soon as possible to cure a cause rather than just managing the symptoms.

Elsewhere in the forum, I have at some considerable length explained why dehumidifiers for caravans in end of season or longer term storage are doing nothing practical, whilst wasting your money, by putting refills in them or running up bills for electric ones. Obviously , its up to individuals to decide if they want to use them, but there is no scientific or financial case for their use in caravan storage

You question the amount of ventilation fitted to caravans, There are regulations in place that determine the area of unimpeded ventilation that must be present in a caravan, and the formula takes into account the number of people that the caravan is designed for, and the inclusion of certain appliances that will use habitation pace air to function. Also there are legal requirements for gas drop out holes at certain places.

Often it's not the statutory ventilation that's the problem, For years many caravan manufacturers have failed to fully install fridges in accordance with appliance manufacturers instructions to seal the front edge of the appliance, and there is often a lot of draught's caused by this failure.

 

[Parksy]

Our damp free caravan is 14 years old.
Like Hutch, we used pledge on the surfaces one year and green algae appeared so we never used it again and the surfaces have no trace of algae.
I move the seat upholstery to allow air circulation and over the winter I leave a couple of windows plus the end washroom window on night latch to allow a degree of air circulation.
I don't bother with so called dehumidifier crystals, there's no point with the windows on night latch.

 

[Beachball]

Thats great, My Corniche was in its 16th year, completely damp free. never used an MC The only reason I sold was that some window seemed it implode and some seemed on the point of exploding.

Well so far all windows are ok

 

[Beehpee]

Hi all, I’ve never used moisture catching devices but rightly or wrongly if people choose to use them so be it, for myself I did yesterday what I have always done, I check for any visible mould on walls and all surfaces, I leave all cupboards open including fridge and freezer and even the oven, I check all the bed cupboards and turn over all seats and mattresses, or to put it simply if something moves I turn it, if something opens I open it, if it’s there I check it, yesterday was a full check of everything I could and it took me a good couple of hours, depending on the weather it could be a couple of weeks or a month when I go again, I also blow down shower pipe with all taps open, first few couple of time it’s a struggle to blow it through but it’s surprising how much you can blow out, battery is kept charged with a solar panel, I might be a bit over the top with my checks but with the cost of the caravan and the stuff in there, I’ve got about £25k invested in there so it’s time we’ll spent in my opinion.

BP

 

[Sam Vimes]

Let me just reset my original post.

There were two issues which while might appear different are related.

1. Damp, possibly caused by water ingress was found during the service and will be rectified under warranty.
2. How to mitigate further damp problems due to storage over winter in a high humidity environment.

Just to address the second issue...

In high humidity conditions and a low dew point, condensation will occur on some surfaces and while most of us probably relate this to a potential build up of mildew/mould, it also has the potential to cause structural problems.

How many of us have seen pools of water at the bottom of windows that have high levels of condensation on them? In the past I've had old houses with the single glazed Crittall Windows which have iron frames. These frames have rusted over the years due to the condensation running down the windows. While our caravans are not as bad perhaps, the possibility still may exist that surfaces and fabrics sitting in 'damp' conditions will suffer structural damage.

In respect of running the heater - Warm air does not necessarily contain more moisture than cold. Relative Humidity is what matters rather than temperature. Some of the hottest places on earth are also the dryest in terms of humidity. What putting on the heating will achieve is to warm up surfaces and prevent condensation from forming. Of course this may require running the heater permanently during times of high humidity which could be cost prohibitive.

Dehumidifiers and absorbers - while it may be considered by some as a total waste of money they do work by reducing the water vapour content locally, in this case within the caravan. Of course the same decision about cost to benefit ratio still must be considered.

Ventilation - the problem with ventilation in a caravan is that its uncontrolled. Basically all that's going on is that outside air is let into the caravan through the various holes. This is the same air that might have a high humidity content which will just add to the internal 'damp' situation. There seems to me little opportunity for adequate air flow around the caravan - prehaps a roof light open would help. However, what ever air movement there might be it may help prevent mould build up but I believe will do little to reduce condensation.

There may well be regulations regarding ventilation points but I wonder if the regulations have kept up with the advances in appliances. Or is it a case that 'we've always drilled holes there in the floor'. I can see that appliances burning gas would need some controlled ventilation but balance flue devices have been around for years. Ok, a gas hob is different. But why is it necessary to drill holes in the floor everywhere there seems to be a control valve and even in places where there aren't?

I'm going to start monitoring my caravan. I have a device that records, temperature, relative humidity and dew point and I'll put that in today and leave it for a while. Then I'll try and see what happens when I put the heater on for a while and then also try some 'damp' boxes.

 

[Jcloughie]

Dont forget the interstitial condensation!!,

A good evaluation, not sure I would agree 100% with it all. For example. It is true that warm air does not necessarily hold more moisture than cold. But it does have the capabilities of holding more. Yes warming surfaces will help in preventing the attraction of condensation. But. It might then be concentrated on any colder areas. And. Unless the heating was maintained, constantly warming then allowing the surfaces to cool could exacerbate the problem.

It‘s a minefield. But best of luck.

John

 

[Sam Vimes]

I think that with sitting outside for some time the temperatures throughout the vans fabric would probably normalise and interstital condensation would not occur.

Of course heating the inside would then create a temperature difference between inside and out but then this is what happens in normal use anyway. Its not as if vans have cavity walls

Yup a minefield and we have to hope we don't put a foot in the wrong place.