Condensation in cupboards

[pophops]

 

The moisture may be finding its way into the trunking, but it's not coming from the trunking. How could that be?

 

Edit: Just checked - there is no moisture inside the trunking.

I did say it was a long shot. Just trying to be of help. Glad you've solved the problem.

[blackrose]

I did say it was a long shot. Just trying to be of help. Glad you've solved the problem.

 

Thanks - it made me go and have a look inside the trunking anyway.

[sueb]

We found the cupboard that held the wine bottles got wet, with condensation running down the bottles. Ventilation is ok if the temperature is the same inside as it is outside. Not liveable.

[blackrose]

I think I might cut a 2" hole at the bottom of each door and put these small vent covers over them.

Edited January 23, 2017 by blackrose

[BWM]

 

Yes, that's it. With the doors off it's drying out already. I've just been down on the floor looking at it and I can feel really good low level airflow along the corridor, so I need to ventilate the doors.

Easiest solution may be to plane 1/4" or so off of the bottom of the doors.

[Lily Rose]

When we were on the boat for a few days at the beginning of December I found condensation low down at the back of a cupboard but also, more surprisingly, there was (much) condensation first thing one morning along the bottom of the panelling opposite the bed. This was out in the open and not far from the back door ventilators.

 

It seemed pretty clear that the straight horizontal line that marked the point where wet wood gave way to dry wood corresponded to the waterline. I've never seen this before, and didn't see it last week when the water must have been just as cold as it was in early December. It was so obvious that I'm sure I wouldn't have missed it last winter at times when the water was iced over.

 

I put a tube heater on the floor next to the panelling and the condensation disappeared pretty quickly (it probably moved inside the cupboard!).

 

I assume it's due to some combination of the air inside the boat being colder at night (with the fire damped down), and therefore less able to hold moisture, very cold water outside the hull, and lower ventilation at night as outer doors are not being opened and the fire is not pulling in as much air from the boat.

[Joe Bourke]

You can get small circular stainless cupboard/cabinet vents, quite cheaply on eBay.

[I Spartacus]

It might be worth just putting in a small fan at one end and a vent at the other and drawing some air through the void area at rear of cupboard . It all goes on the dew point and lack of ventilation, just keep a little space clear at the back of the cupboard.

You must remember that warm air holds more moisture in it than cold air so when it cools it condenses out at the coldest point as in this case was at low level and below the water line in the cupboard. Glad you spotted it early and can now get it sorted.

[Jess--]

 

The moisture may be finding its way into the trunking, but it's not coming from the trunking. How could that be?

 

Edit: Just checked - there is no moisture inside the trunking.

looking at your 2nd picture it looks like the trunking itself has condensation that has formed on the outside of it.

 

could it be that the trunking is getting a cold draught through its inside from the bow thruster at the front and somewhere at the rear, if that was the case it would make the trunking a lot colder than anything else in the cupboard and could cause the condensation problem you are seeing (which from the photo's appears to stay close to the trunking)

 

I would try sticking something in one end of the trunking to try and block any airflow and see if it made any difference

[blackrose]

Easiest solution may be to plane 1/4" or so off of the bottom of the doors.

 

If you look at the picture in post 20 you'll see I'd need to plane off a bit more than that!

You can get small circular stainless cupboard/cabinet vents, quite cheaply on eBay.

 

Thanks, I'll have a look.

It might be worth just putting in a small fan at one end and a vent at the other and drawing some air through the void area at rear of cupboard . It all goes on the dew point and lack of ventilation, just keep a little space clear at the back of the cupboard.

You must remember that warm air holds more moisture in it than cold air so when it cools it condenses out at the coldest point as in this case was at low level and below the water line in the cupboard. Glad you spotted it early and can now get it sorted.

 

It's almost all dried out now so it doesn't need a fan, I'll just leave the bottom of the cupboards empty and vent the doors.

looking at your 2nd picture it looks like the trunking itself has condensation that has formed on the outside of it.

 

could it be that the trunking is getting a cold draught through its inside from the bow thruster at the front and somewhere at the rear, if that was the case it would make the trunking a lot colder than anything else in the cupboard and could cause the condensation problem you are seeing (which from the photo's appears to stay close to the trunking)

 

I would try sticking something in one end of the trunking to try and block any airflow and see if it made any difference

 

That's good lateral thinking but it's not what's happening. There's no airflow through the trunking. The only reason the trunking has condensation all over it is because it's in the vicinity where the condensation is forming.

[cuthound]

If it is caused by condensation forming on, and dripping off the trunking, then insulating the trunking may be an easy a d effective option.

[blackrose]

If it is caused by condensation forming on, and dripping off the trunking, then insulating the trunking may be an easy a d effective option.

 

No it's caused by condensation forming on the coldest areas which is the bottom of the wall - because that's the area where heat transfer to the water outside is the greatest (unless it's very cold and windy outside). This is true on any boat. Add lack of ventilation to that and condensation will form.

 

The trunking being the cause is I'm afraid a red herring and it doesn't make any sense. It might make sense if as Jess said there was cold airflow through it, but that's not happening.

A lesson for us all. There should be no unventilated spaces anywhere inside a boat. Most boats will have a few unventilated cupboards, blocked-in voids, etc., and they should all be provided with vent holes.

 

I guess I should check inside the boxed in water pipes on the other side of the boat too? Does anyone actually vent that small space?

Edited January 24, 2017 by blackrose

[David Mack]

I guess I should check inside the boxed in water pipes on the other side of the boat too? Does anyone actually vent that small space?

 

I have vented a similar box over pipes in our kitchen at home. It is against a cold outside wall (solid stone, uninsulated), and a few years back I had a burst in a pipe which ran behind the cupboard which was there at the time.

[Murflynn]

 

 

I guess I should check inside the boxed in water pipes on the other side of the boat too? Does anyone actually vent that small space?

it depends on whether you think condensation inside the box is a problem. it usually is - mildew, rot, etc.

[Naughty Cal]

I think I might cut a 2" hole at the bottom of each door and put these small vent covers over them.

We could do with a couple of these (in stainless not brass!) for one of our cupboards on the boat.

 

It doesn't feel damp and is usually dry when we pull all of the contents out but it occasionally gets a bit of a fusty smell if not emptied for a while so I guess the air flow isn't very good or is none existent in there.

[OldPeculier]

Not a solution to this problem but for anyone planning a fit out, I would highly recommend running hot water heating pipes through cupboards. I did this (for ease rather from a design point of view) and all these cupboards stay damp free while the one on the other side of the boat suffers from condensation if I dont leave the door slightly open.

[blackrose]

it depends on whether you think condensation inside the box is a problem. it usually is - mildew, rot, etc.

 

I've never noticed any condensation inside the boxed in pipes although I can't say I've taken every section apart. Do you vent it on your boat or do you have exposed pipes?

We could do with a couple of these (in stainless not brass!) for one of our cupboards on the boat.

 

It doesn't feel damp and is usually dry when we pull all of the contents out but it occasionally gets a bit of a fusty smell if not emptied for a while so I guess the air flow isn't very good or is none existent in there.

 

I've just ordered some of these following Joe's recommendation posted earlier- 1 for the bottom of each door. They're a lot cheaper than brass vent covers.

 

I'll give them a light gold spray before fitting them.

 

http://www.ebay.co.uk/itm/301827690145?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Edited January 25, 2017 by blackrose

[Naughty Cal]

 

 

I've just ordered some of these following Joe's recommendation posted earlier- 1 for the bottom of each door. They're a lot cheaper than brass vent covers.

 

I'll give them a light gold spray before fitting them.

 

http://www.ebay.co.uk/itm/301827690145?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

They wouldn't really be in keeping with the fit out of our boat.

 

Let us know how you get on with them though.

[Murflynn]

 

I've never noticed any condensation inside the boxed in pipes although I can't say I've taken every section apart. Do you vent it on your boat or do you have exposed pipes?

 

 

I've long since moved on to a small fair weather yogurt pot, Mike, but I did not enclose things unnecessarily. All pipes were behind the plywood linings.

[Joe Bourke]

Circular horse brasses can make nice quirky vents with a little imagination. Lots of brass items are practically given away nowadays and could be put to good use on your olde worlde boats.

[blackrose]

I've long since moved on to a small fair weather yogurt pot, Mike, but I did not enclose things unnecessarily. All pipes were behind the plywood linings.

Which is in itself an enclosed space, no?

 

Besides, pipes installed behind linings sound difficult to access.

Edited January 27, 2017 by blackrose

[OldGoat]

Back in the days (when hair-shirt-boating) was the norm, folks ventilated everything. It was the sensible thing to do.

So muggins put lovely brass louvered vents on absolutely everything, cupboards, doors, storage boxes, some access to bilges, front of boat, rear of boat.

The brassfounders (well Midland whatsits at Braunston bottom lock) did well...

The same with windows, drop back vents everywhere.

I still get some condensation - but norra lot.

 

If you shut yourself in a series of tightly closed boxes, your bodily exhausted have got to go somewhere - and that's what happened here....