Ideas for keeping a campervan damp-free through winter

Our venerable old T5 camper may only get driven once every couple of weeks through the winter. For the rest of the time he sits parked up on the usually cold, usually damp, very often actually in the cloud hillside what we live on. Being the age he is (twenty), he’s not as well sealed as he was, and this damp, cold and cloud seeps its way in and he can end up being pretty moist inside and we have mould spots appearing on the headlining.

So, I’m thinking of ways of looking after him through this winter. One idea is to keep him hooked-up and put a small oil radiator in him, set on low and on a timer, to get some warmth in there for an hour or so a day. I also wondered about a couple of 12V fans to keep the air moving around. Anything else I could/should be thinking of?

If you are thinking of some kind of timed device to run during the day, I think you would be better off seeing if a dehumidifier could do this.
I am not sure if you can get one that will work like this. I have an Electriq dehumidifier and I don’t think the timer function is sophisticated enough & you can’t leave it switched on with a ‘plug-controller’ to turn it on & off instead.

Small dehumidifier did wonders in my van last year!

I use these a couple of these silica bags in my MG TF  (which isn’t watertight!) they keep the worst of the damp off. And there’s been no mould on the underside of the soft-top since I started with them…

https://tinyurl.com/4vtysp5e

…you’d probs need half a dozen in a van though.

If you can get mains to it, a dehumidifier would be a good idea. You’ll have to empty it every few days.

Cat litter in a sock.

dehumidifier with app

This is the first one I have found, so probably better ones around. It looks to have an app & you can set schedules to turn it on & off under certain scenarios.

If you go down the dehumidifier route, just make sure you investigate what type would be best. I think if it is sitting ‘outside’ in a car, you would want a dessicant one, rather than a compressor as I don’t think they work as well when the temp drops.
You’ll also need to empty the tank on the dehumidifier every so often.

Having another quick look, it seems they do a dessicant one with the same app functionality.

dessicant dehumidifier with app

I have a yellow ebac dehumidifier, rotary controls, so it starts as soon as you put mains to it. You can run a tube out from the bottom so there is no tank to empty. If you ran that from a humidistat socket then it would be fit and forget.

Drive to south of France

Park up and open all the doors and windows

Put kettle on

Return home in spring

If that’s not practical, a dessicant dehumidifier is your friend. Probably a meaco junior, excellent bit of kit with good back up

I was going to suggest driving south and heading to Spain on a ferry, but given the recent climatic conditions that might not be much help.

Hunt down the leaks first. Maybe tarp or cover over it as well?

I have added an external plug next to ours. Once a fortnight it is plugged in to charge battery and run the de-humidifier in there for about 4 hours. We leave even duvet and pillows in the cupboard and they have not got damp.

I find after winter camping an hour of heating an dehumidifier is needed, with things like curtains loosely hanging etc is needed.

Ours is driven about twice a week, used every other weekend.

I have two of those 1kg silica bags, one lives in the car, one lives on a radiator in the house, I just swap them every month or so.

Could be worth some time going around checking/cleaning/treating seals though as well as cleaning out drain holes etc. If water is getting in then it’ll keep getting worse even with a dehumidifier going.

As above, i use a ‘dumb humidifier’ connected to a 7 day timer, i just run it every other day

I have found a simple and cheap solution. I have one of those bags that absorbs moisture which I leave on the dashboard. That costs about £7. The other part of it is to get those wind deflectors for the front windows if you don’t already have them. They are a great thing anyway as you can then camp with the windows open without worrying about the rain coming in. I then leave both my front windows open a little bit. You can’t tell that they are open from the outside but it makes all the the difference to moisture in the van.

Would it be possible/worth trying to erect some sort of shelter for the van?

It’s one thing to keep heating/dehumidifying/desiccating a vehicle, but cover (even a basic lean-to) will help reduce the routes by which moisture can make it’s way onto the vehicle in the first place. Do a little prevention as well as cure?

bowls of salt placed around

We just put the domestic dehumidifier in periodically to dry it out and leave a silicon bag in all the time. Seems to work.

One idea is to keep him hooked-up and put a small oil radiator in him, set on low and on a timer, to get some warmth in there for an hour or so a day.

I’m not sure heat would get rid of any damp without air flow.  As said, a [dessicant] dehumidifier on a timer would be best in that [low temperature] situation

bowls of salt placed around

Aka salad in Scotland

A 20 year old T5 is going to be leaky unless you fix all the leaks. Mouldy headlining? Well, the sunroof drainpipes block at the outlets then leak at the joints behind the headlining. The roof gutter bolts leak as standard at that age as the gaskets will be perished, so that will also make the headlining damp. Both those are easy and inexpensive fixes.

Sliding windows will leak at the tiny drain outlets, giving more moisture inside.

Have you got room for something like this…

https://www.machinemart.co.uk/p/clarke-cig81015-heavy-duty-instant-garage—da/?utm_source=google&utm_medium=ppc&utm_campaign=GS-140613570&gad_source=1&gclid=EAIaIQobChMIu7LUjcfeiQMVXqVQBh29ATA2EAQYASABEgLI4fD_BwE&gclsrc=aw.ds

I have two of those 1kg silica bags, one lives in the car, one lives on a radiator in the house, I just swap them every month or so.

Is that introducing quite a lot of moisture into your house?

Cheers all.

Drive to south of France

Park up and open all the doors and windows

Put kettle on

Return home in spring

I wish, that’s the retirement dream

Hunt down the leaks first. Maybe tarp or cover over it as well?

It’s one thing to keep heating/dehumidifying/desiccating a vehicle, but cover (even a basic lean-to) will help reduce the routes by which moisture can make it’s way onto the vehicle in the first place. Do a little prevention as well as cure?

I get what you mean, but it’s not leaking as such, it’s just tired door/window seals and the issue is not moisture from above, it’s moisture from all around.  A typical winter day ChezIHN –

The other part of it is to get those wind deflectors for the front windows if you don’t already have them. They are a great thing anyway as you can then camp with the windows open without worrying about the rain coming in. I then leave both my front windows open a little bit.

Yep, got window vents, and a boot hatch lock opener thing, and they’re great when camping, but I’m not sure about leaving the windows open a crack through the winter, won’t that just make the mist ingress worst?

I never thought about a dehumidifier though, seems pretty obvious now…

A lot of talk above of timers/smart control/humidistat plug to control a humidifier. Seems a faff compared to just buying a dehumidifier with built-in humidistat control eg. this one. I have a previous version of that in my cellar set to a level that will keep the mould off things and it just comes on and off as needed. I’m lucky that I have a drain for it to drain into so it’s totally fit and forget. Linked model is dessicant type, which I think is probably best for living in a cold vehicle.

We did ours with hookup, oil rad and timer, plus a couple of those standalone crystal dehumidifier plastic box things, (and put in fridge vent restricters and drained the plumbing etc completely)

FYI, apparently you’re meant to silicon spray all window door etc etc black rubber seals etc before shutting up as it stops them sticking when left shut for a long time.

other part of it is to get those wind deflectors for the front windows if you don’t already have them. They are a great thing anyway

Git a link?

I tried to buy some a few times but got utterly overwhelmed by choice!

Cat litter in a sock.

Well that will definitely help if anyone wees in your shoes

Git a link?

I tried to buy some a few times but got utterly overwhelmed by choice!

I don’t know if mine are exactly these ones, but they’re basically these ones

https://www.veedubtransporters.co.uk/shop/vw-t5-t5-1-dub-style-black-wind-deflectors-in-channel/

And if you haven’t already, get one of these, really help for ventilation when you’re sleeping in it (or leaving it in the campsite)

https://www.ebay.co.uk/itm/315720223015?var=0&mkevt=1&mkcid=1&mkrid=710-53481-19255-0&campid=5338268676&toolid=10044&_trkparms=ispr=1&amdata=enc:1soCBKYmRSKmomGEr_QNQrg3&ff=11&customid=Cj0KCQiA_9u5BhCUARIsABbMSPt4Vy-nNE4IAT6SuYkyFVlHWBW-_FVexNkVb1Bc7KHoGO-tOcZtJWYaAk8FEALw_wcB

This stuff is pretty good at stopping old window seals from leaking.

https://www.amazon.co.uk/Captain-Tolleys-Creeping-Crack-sealer/dp/B003T6EJ9A

Kampa Damp Buster

I have a cheap dehumidifier but remember all these things rely on getting water out of the air, so they work less well when it’s cold. UK winter conditions are pretty challenging for a lot of them tbh. Condensing dehumidifiers (like mine) also need a bit of temperature to operate. I really like the bag type, they’re more faff but they’re really undemanding, just get twice as many as you need and have one set in the vehicle and one in the house “passively” drying on a radiator and swap over when you remember.

Don’t rule out manual extraction- you can get a lot of water off windows with a window vac frinstance (and they’re handy to have for other stuff, I’m glad I have mine), in a lot of weather windows are the perfect condensing surface. A lot of vehicles will also have a “damp spot” ie a favourite place for water to gather, and it can actually be pretty useful if you can get water out of it. Some cars like to fill their spare tyre well frinstance.

Keeping water out is definitely better and it doesn’t have to be all or nothing, every drop you keep out helps. I really like gummi pflege for seals, it’s not as powerful a “seal fixer” as some so won’t help with really bad ones but it’s easy to use and very gentle, does no harm. Also helps stop seals freezing which can be a problem when a damp or leaky vehicle gets cold.

Or stick it in an air chamber which has a small fan blowing air through the car / van 24/7.

https://www.carcovershop.co.uk/airchamber-protection.php

Some cars like to fill their spare tyre well frinstance

I had a Mercedes car like this. Turned out it was a design/construction flaw. They eventually recalled the vehicles affected for a fix.

Well in the construction world I would recommend ventilation and insulation to aid in control of damp issues, plus search for the leak, so that’s basically what you need to do there.

Can you get some of those plastic guards that allow the windows to be open to give some ventilation inside?