2000 Bavaria 34 - Winter Ventilation/Condensation

[LinTeal]

If I do nothing is my interior/ upholstery etc likely to suffer over the winter.Ideally I would like to leave some windows,hatches ajar for ventilation but cannot see how to achieve this without rain  getting in.The boat is afloat in the Solent.
I may use tube heaters although would prefer not to.Any thoughts please ?

[geoff]

On my 40 cc I use permanently mounted computer fan on a perspex false window ,which slots into the cockpit interior window . It is supplied with 12v from my solar panels , so it is always on if there is daylight . The power take off is before the voltage regulator so I found a half amp chip VR which prevents the fan going mental. If we are on the boat I just turn it off [its a bit noisy] Geoff

[fjoe]

I am blocking the ventilation holes to avoid additional humidity from fresh air.
All upholstery stays on board. Boat on land but outside,
We set up 2 air dryers with sal. D and due to the corona situation we left our boat from end of September until  1st of July. I think the dryers were used up in January.
When we came back everything was well.
Frank

[IslandAlchemy]

Can't you leave some hatches on vent?  That's what I do and no rain gets in.

[LinTeal]

Thanks .for comments.
Island Alchemy,when you say "on vent" do you mean hatches partially opened but still locked,This had occurred to me but I thought in adverse weather rain would get in ?

[Clivert]

Our 2001 34 stays afloat all winter" on our Port Solent berth.
 Sometimes we put a dehumidifier for a week or two but don't have a problem except when the original Rutgerson hatches leaked, but they have now been by Lewmars and all is well.

[LinTeal]

Thanks Clivert,also Port Solent H pontoon  !

[IslandAlchemy]

Thanks .for comments.
Island Alchemy,when you say "on vent" do you mean hatches partially opened but still locked,This had occurred to me but I thought in adverse weather rain would get in ?

Yes that's it. Open them to the slot in the latch and you can lock them there.  No rain will get it.

[Yngmar]

We've just returned to the boat after a hot summer followed by a very wet and cold autumn/winter. We were happy to find everything was dry and mould free. The boat has a single dorade vent on the bow and two vents at the transom. That is enough for ventilation when not occupied. The dorade is opened and pointed away from the usual autumn storms (ours has a seal to close it in rough weather) and all vents covered with mosquito netting to keep insects out (rodents won't fit the vent grille outside). The boat must be leak free, as water sitting in a puddle somewhere (bilge, locker or some inaccessible space) will cause much higher moisture levels.

If there's people on board which breathe out liters of moisture, it's a wholly different story and you need a dehumidifier (or heater with lots of ventilation, but that's a bit wasteful).

We also flushed the engine with fresh water and filled the tanks with a double dose of chlorinated water (which needs replacing now - only evil bottled water until then).

[Odysseus]

I put these Crystal's in a container each winter, never had any mould what so ever, I buy them off EBay.

Odysseus
Bav38

[LinTeal]

Many thanks to you all,v helpful.

I will have hatches on vent,leave some crystal dehumidifier pots around,upend upholstery and leave cupboards open.Touch wood ,bilges etc bone dry.

Hopefully that will do the trick  !

I had better get on with it .

[Yngmar]

Personally wouldn't leave the hatches on vent, as at least our Gebo hatches do let water in on the vent setting when it's a proper storm with rain flying sideways. Or hail bouncing off the deck as we had this morning! 

The dorade boxes are designed to separate water from air and work well. There's flush ones that won't catch sheets too: https://www.tcschandlery.co.uk/vetus-ufo-stainless-deck-ventilator/p15469