Desiccant in sailboat over winter

[Windtherapy]

Just curious if others put desiccant of some type in their sailboats over the winter (for those who are unfortunate to to have winters)? I just took the tarp off my boat and opened it up due to just finally getting 60+ degree weather. Noticed a tad of humidity on mainly the laminate counter tops etc. which I am sure is normal however, just wondering if next year I should put something in there like a bunch of the DampRid containers.

 

[Don S/V ILLusion]

If you have anything more than a minor moisture problem, any amount of a desiccant will quickly become saturated rendering it ineffective. Frequent replacement is the only option unless you allow for adequate ventilation in which case you obviate the humidity problem.

 

[John T1594]

Yes, I usually put two or three of the large damp-rid buckets in the boat (H340) over the winter to keep things dry. I have no deck leaks and my bilge is always dry when I open the boat in the spring. I should mention that I also have a solar Nicro exhaust vent for the main cabin.

 

[jdhohmann]

We always have spot mold throughout boat in the spring. This year we put a fan on all winter as well as 3 bags of charcoal to see if this eliminates the problem...

 

[Rich Stidger]

I place 7 pails of calcium chloride around the cabins to absorb water and keep the humidity low. Never had a problem with mold on the cushions in 8 years of this storage method.The pails of calcium chloride are set up as follows: Buy plastic pails and colanders at the dollar store. Put a colander in the top of each pail and place several scoops of calcium chloride in the colander. The calcium chloride will absorb the moisture and then it will drip into the bucket. My 7 buckets collect 2 full buckets of water over the winter and spring. Most of the water appears in the spring.The calcium chloride can be purchased at any garden supply store and it is the same stuff in the "damp-rid" pre-loaded buckets that you can buy at the boat stores for 10x more $$.

Be sure to wet-vac all the water that is standing in the bilge. A large volume of water will over-whelm the buckets of calcium chloride.

 

[Windtherapy]

Thanks for all the awesome replies. I will definitely do something next year even though it was hardly any moisture this year after sitting covered for months. I am thinking about taking the roof off my pole barn an go from a 4/12 pitch to a 8/12 pitch roof and adding a large garage door and keep my boat inside my heated pole barn. Not only is it dry but I can putz on it all winter then. 6 months of winter gets boring.

 

[Jalepeno]

I use three DRIZAIR and anti-spill tray desiccants (using calcium chloride) over our wet winters. One in the engine compartment, one on the galley counter and one in the head. I've also the Caframo Stor-Dry fan units but found, as expected, they do not remove moisture on their own. I now also use an Eva-Dry EDV-2200 solid state dehumidifier with plastic hose from its tank to the galley sink and a Caframo electric heater set to the lowest setting. Most boats are in the water year round and I often go sailing in the winter. Here on the Canadian west coast the main problem is not mold but just dampness. The relative humidity is 100% whenever it rains and it may rain for days or sometimes for weeks before a dry spell. We do not normally get snow in the winter or even freezing temperatures except at night for a few weeks. I've found it is best to keep the boat as air tight as possible or it will inhale moist air at night with the water condensing on ports and underside of the decks and then it will exhale the dryer air when it warms up during the day. This cycle repeats itself every day and you can have the condensate drip inside. The situation may be very different in other geographic areas. Also we do not have moisture problems during the summer.

DRIZAIR

Eva-dry Edv-2200 Dehumidifier

 

[JamesG161]

The calcium chloride will absorb the moisture

Tip! That CaCl2 is "rechargeable". Simply heat dry it or put it in your summer time attic.

If you have anything more than a minor moisture problem, any amount of a desiccant will quickly become saturated rendering it ineffective.

The amount of drying agent is determined by the amount of water in the cabin air during the winter.

Here is the bad news....
The dryer the air inside your cabin, the more the moisture wants to enter the cabin.

You might use an electric dehumidifier ( with controls ) with condensate discharge outside the cabin or sealed container like picture above.
Jim...

 

[Maine Sail]

I simply create a chimney effect by opening both sink drains, leaving the sea strainer open, and cracking my hatches & ports plus running a Nicro. The bilge is always bone dry and this is a must. Zero humidity issues. As for ventilating and using desiccant (most boats leak like a sieve), I've never understood how dehumidifying the World worked. We don't and won't use any desiccant as there is no way we are ever going to dehumidify Casco Bay.

Over the winter, when boats are covered, I am on multiple boats per week, seven this past week alone, many who use Damp-Rid, kitty litter etc. and by far and away our boat is the cleanest smelling and driest boat I set foot on... Ventilation & air turnover/movement is the key...

 

[Rick Webb]

Check the pool stores for the Calcium Chloride, that's the cheapest place I have found. You can place the colander in the sink and let it drain out the boat but I have heard that stains metal sinks so watch out for that.

Jim, our environments are similar and I actually used to keep my boat in Long Beach. I found a 100 watt light bulb took care of the moisture in the boat.

You do not need to heat the boat just have it at least as warm inside as the outside. Of course now it is vey hard to find 100watt bulbs. (I have a stockpile)

There is a gadget called a Golden Rod that does the same thing.

 

[Windtherapy]

Ya I was thinking of using the rod style. I use it in my gun save year round and works well.

All these replies are great. Thank you. I really never thought about cracking my port holes. No wasps/bee's In the winter and that would probably help.

 

[JamesG161]

Ventilation & air turnover/movement is the key...

That maintains almost constant humidity!
The problem occurs when there is a rapid decrease in temperature, which goes be low the "Dew Point". The southern climes are much more likely to have dew inside as spring approaches.
Jim...

 

[Maine Sail]

That maintains almost constant humidity!
The problem occurs when there is a rapid decrease in temperature, which goes be low the "Dew Point". The southern climes are much more likely to have dew inside as spring approaches.
Jim...

72% RH today 24F last night and 63F right now. We have dew, or frost as we call it when the temp drops below 32F, quite regularly.. The key is to allow the boat to warm up at a comparable rate, inside and out, and ventilation helps this. You'd be amazed at how much fresh air a 1" sink drain is pumping into the boat, you can literally feel the breeze...

 

[51RD55]

I simply create a chimney effect by opening both sink drains, leaving the sea strainer open, and cracking my hatches & ports plus running a Nicro. The bilge is always bone dry and this is a must. Zero humidity issues. As for ventilating and using desiccant (most boats leak like a sieve), I've never understood how dehumidifying the World worked. We don't and won't use any desiccant as there is no way we are ever going to dehumidify Casco Bay.

Over the winter, when boats are covered, I am on multiple boats per week, seven this past week alone, many who use Damp-Rid, kitty litter etc. and by far and away our boat is the cleanest smelling and driest boat I set foot on... Ventilation & air turnover/movement is the key...

Boats to be launched soon, but we will keep this in mind after haul out. Now that the hoses in the head are all gone and the rotten wood replaced, the boat smells quite lovely! We bought 2 Nicros at the boat show this year and will be putting them on soon. Any suggestions where they should be placed? Thanks.

 

[Rick Webb]

That maintains almost constant humidity!
The problem occurs when there is a rapid decrease in temperature, which goes be low the "Dew Point". The southern climes are much more likely to have dew inside as spring approaches.
Jim...

I'm with you, Jim.

Down here humidity below 80% is low, around 90% is almost expected.
There are all sorts of places on the boat for air to seep in. Cracking a hatch makes it more difficult to maintain a temperature above the outside so as not to have a bunch of condensation on everything. I have a Day Night vent but close everything up between that and the light bulb my boat is bone dry all the time.