One of the other scourges of
winter sailing, we’ve discovered, is condensation. When warm moist air inside the boat touches
the “walls” (hull) or the windows, the result is a continual cold-sweat inside
the boat. A little bit of this is
manageable – you just wipe it up with a sponge from time to time. A lot of it, however, leads to mildew, ruined
cushions, mouldy food stores, a damp feeling everywhere, and nights punctuated
with Chinese water-drop torture.
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| Dehumidifier (only marginally helpful.) |
I had taken all the sensible
precautions I had learned: turn on the
heat and open some windows, increase ventilation, turn cushions on-end when not
in use to increase air flow, always open a porthole above the stove when cooking,
eliminate cotton, put food in plastic containers, etc. I even bought a small dehumidifier (the
chemical absorbent kind) and we recently just installed some great “akwamats”
under our bed cushions. These thick mats
of latex-coated coconut fiber help increase air circulation and insulate
cushions from the bulkhead walls. (They
stink a little bit, though…hoping that will go away with time.)
But one month in the boat yard
this winter without much ventilation highlighted several weaknesses of my
strategy that beg to be remedied.
Patrick, ever the pragmatist, suggests we simply stop navigating when it’s
cold, but I am convinced that even wintering-over in warm places will still
lead to humidity problems at some point and measures must be taken.
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| Akwamats |
This epiphany came to me last
week when I discovered that condensation had ruined my breakfast tea, properly
stored in a plastic container. Even some
of the herbal teas in individual plastic-like sachets had to be thrown
out. Okay, admittedly, the lid to the
plastic container may not have been fully sealed, but still… this meant war.
As I began looking around the
boat, I quickly identified several problem areas. First, the former owners of the boat ripped
out all the wall linings and simply painted the surfaces a matte white. When I first visited the boat, I loved the
effect – clean and neat. Nothing is
worse than dingy sagging mildewed wall lining.
But this facelift also means that there is no longer any insulation
between the cold bulkhead and the warm air, so we now have lots of surface area
for condensation to form. This is
particularly troublesome inside the food and clothes lockers.
The other big culprit is the
metal rims around the portholes and hatches.
This is where the majority of condensation forms. In the mornings, after a night of breathing
in a closed environment, the drips are everywhere, but mostly concentrated on
these cold metal surfaces. One morning
last week, the hygrometer read 81% while the temperature was only 8° C / 46°
F. With a dew point of 5°C, we were very close to creating our own rain
clouds. In such conditions, wiping drips
off the window frames with a sponge works for about 1 minute before the beads
re-form. Of course, the answer here is
ventilation, but who wants to crawl out of a warm sleeping bag and open the
windows in a howling sub-zero wind even before having that first cup of mouldy
tea ?
After reading several blogs from
live-aboards in cold climates, I have a few new tricks I’m going to try.
My favourite idea and probably
the one least likely to work is Anti-Condensation Paint. This paint, readily available and reasonably
priced, was developed for bathrooms and kitchens, and a few blogging yachties
have said it works well for them on their boats. The paint contains micro-beads of glass, a
great insulator. And it’s available in
matte white, so we can test it in a few places before committing to a full
interior paint job.
| French version, anti-condensation paint with glass micro-beads. |
The next idea is insulating the hatches. You can make or buy insulated covers that you
put on the outside of your hatches. Apparently,
the camping car industry is way ahead of us on this. Some of the fancier ones are actually a bit
oversized, allowing you to leave the hatches open a crack to improve
circulation.
The third trick is a simple one,
but one that will force us to abandon our ecological moral
compasses. We must accept to turn the
heat on full blast and open all the windows.
The idea pains me, and yet, it’s the best way to get rid of
condensation.
I figure that by the time I
implement these tricks, the weather will be warmer and this won’t be an issue. To add insult to injury, I just read that the
anti-condensation paint can’t be applied in temperatures less than 12° C / 54°
F ! I guess the bright side to all this
is that I can strike “painting” right off my list for the next couple of weeks. Lesson learned: you must winterize your boat
BEFORE winter !
For more articles on winter sailing, visit The Monkey's Fist !
For more articles on winter sailing, visit The Monkey's Fist !































