A different perspective on FullTiming in Winter --Long!
Pete Dumbleton
Pete
************
LiveAboard Magazine & Marine Chandlery
Living With Winter
The following is a compilation of various letters from boaters and how
they have
dealt with the problems of winter condensation and heat.
I have been interested in the current letters concerning keeping warm
in the winter.
Having spent 11 years aboard various boats I did find that warmth is
of primary
importance in the cold winter months in any part of the country.
I found that small wood heaters are available for boats and produce a
wonderful dry
heat. In fact the one I had required a kettle of water on top to add
humidity. I can still
remember the winter storm in 1982 when the snow was piling up and I
was walking
around inside in a pair of shorts and "T"shirt. You get some strange
looks from
people passing by during such times. The particular stove we had would
accept a
lump of coal for keeping the fire going all night.
Still available in many areas are the CAT heaters that use propane and
are very
effective in small spaces. We heated our Columbia 34 quite nicely with
our
thremostatically controlled CAT heater.
One last thing to remember for those electric heater folks. Keep the
air moving. If
possible leave windows or hatches open a little for good air movement.
This will aid
in keeping mildew and condesation to a minimum. Here's wishing you all
warm
evenings and toasty mornings durning the next couple of months. Gentle
breezes...
Ric Whitson
--------------------------------------------------------------------------------
One of our readers wrote with some questions. He was wondering where
in the boat
the dehumidifiers were placed and where he could purchase the 3/4"
closed cell
foam used to insulate the boat.
The closed cell foam is available through Tacoma Foam Rubber in
Tacoma,
Washington. They get their rubber in approximately 4 foot by 8 foot by
3 foot
bisquits. They then cut it into any size or shape desired. I have had
matresses and
cushions custom cut and laminated by them and they matched the
template perfectly
on odd shaped pieces. The closed cell foam as I recall was a layer of
1/2" with a
1/4" layer laminated to it.
One side had white vinyl on it and we used it for the finished side
and used contact
cement to glue the rubber faced side directly to the fiberglass hull.
We cut out the
exact size (or as close as possible) to fit in closets and cabinets.
We then used duct
tape on the edges to seal out moisture. Anyplace the warm air can
contact the cold
hull there will be frost and/or dew. We also covered the through hull
bolts from our
sail rigging. It had been in the sailboat for about 9 years when the
boat burned out
from under us and was working beautifully.
The only thing I had to do in those 9 years is replace a piece of duct
tape
occasionally. As per the dehumidifiers, it doesn't really matter too
much where you
put them as they have fans that circulate the air and relative
humidity disburses
throughout the boat and eventually evens out as does temperatures if
the air is kept
moving. I have 2 on my current vessel and turn the one closest to the
source of
humidity on. If I am cooking a big pot of pasta I turn the one in the
galley on. I usually
turn the one on in the stateroom as it is closest to the shower.
We have not had any snow in Petersburg, Alaska yet this year (yes you
read it
correctly and it is true) but the temperature is hovering in the 20's
and teens with the
clear skies. 2 nights ago I cooked up some linguine and noticed the
galley window
starting to fog up. I turned the dehumidifier on until I sat down to
eat and the windows
were then clear. I haven't turned either on since. My boat is now 72
degrees with
about 30% humidity. If there are any other questions, feel free to
contact me and you
may give out my address to other boaters. My present boat was
purchased in Fort
Myers Fla. and brought to Alaska via Panama. I do not consider myself
an authority
on tropical sailing. I do however know how to survive in Alaska and
cruising in the
Temperate rain forest. I would be happy to help anyone planning a trip
to Alaska.
Sincerely,
Dean Andreasen
Battling Condensation
Some time ago I posted a long 'discussion' on condensation aboard and
various
ways to deal with it. Since then I've gotten some mail that points out
an interesting
fact. You can have relatively dry air and still have a water
condensation problem
(and a dehumidifier, heater and ventilation might not help).
The cause is, again, cold surfaces, such as fiberglass hulls and
windows. Example,
we live aboard a 40 foot sailboat, have a dehumidifier, heat the air,
and have
reasonable ventilation. BUT, the warm air holds more moisture than
cold. The
dehumidifier can remove significant amounts of moisture from the air,
but to live in
the air we breath, you still need about 50/60% relative humidity or
you get bloody
noses from the dry air and the wood on you boat (joinery) will start
to separate. What
happens is that the warm air comes into contact with the cold surface
and the
moisture condenses out (the temp is below the dew-point for the air
and the
moisture content). I've noticed pools of water forming in the bottoms
of cabinets on
the shelving where it's run down and accumulated. The problem is
severe where air
is trapped (poor ventilation) and where cushions and the like (books
as well) come
into contact with the hull (bye bye books).
An obvious solution is to insulate the hull, adding (for instance)
closed cell foam
insulation (like the 1/4" thick blue-board sold in Home-Depo) to the
hull, but you've
got to glue it down firmly to prevent airflow behind. To add a nice
touch, cut the foam
boards to fit first, then apply a nice fabric to the outside surface
before using a good
contact cement to adhere the board to the hull surface. The problem
here is that you
can't do this everywhere, so you've got to do what you can and run
fans during the
day to dry up the accumulation of water before it gets to be a
problem. Putting the
insulation between the hull and any cushions you *can't* move would be
a minimum.
Drilling holes to add ventilation to cabinets against the hull that
you don't want to
insulate might be another minimum stance to take. This is a passive
ventilation and
may not gain you much, but if you can add a 'goldenrod' heater to the
bottom of the
locker, the heat will rise and create a warm ventilation to help drive
off moisture.
In a real cold snap, you will still have problems because of the cold
hull and window
surfaces. You just have to live with it, dealing with it as much as
possible and drying
out as often as the weather permits.
I'm not a rep for West Marine, but they sell an "Air Dryer" that runs
off of 110. They
call it a dehumidifier but it's really just a low watt heater (less
than an amp) with the
added feature of a fan to circulate the warmed air and can warm the
air in closed
lockers, like under our aft cabin bunk for instance. They also sell
the golden rod
things, but buying a lot of them can get costly at about $25 each
(10-100 cu.ft.
recommendation).
I do not recommend the chemical dehumidifiers. Done it, been there,
thrown away.
Still living aboard,
Darwin Boblet & Family
Dragon Lady
Originally posted December 15th, 1996
I read the article about damp boats and mildew with great interest. We
live aboard a
50 foot aluminum trawler in a temperate rain forest in Southeast
Alaska. We receive
in excess of 110 inches of rain per year and temperatures down to as
low as minus
20 degrees. We have lived aboard for about 15 years now and we have no
problem
with humidity inside the vessel. We do have to scrub some green off
the deck in the
spring from the constant snow and rain, but no problem inside. This is
our second
vessel we have lived aboard in Alaska.
The first was a 50 foot ketch of fiberglass construction. It was
necessary to add 3/4
inch of closed cell foam to the inside of the hull inside all lockers.
The foam has a
vinyl coating for easy cleaning of spills. We simply cut and glued it
to the hull with
contact cement. We had a Webasto hot water furnace and a dehumidifier.
The
water lines on the webasto ran entirely around the vessel through all
lockers. We put
an extra coil in the towel locker so when we got out of the shower,
our towels were
heated to 140 degrees. The boat kept itself at 72 degrees all winter.
That boat
burned out from under us in the summer of 91.
We bought our current vessel in Florida and brought it to alaska via
Panama in the
spring of 1992. We did have to install a heating system to go with its
3 air
conditioning units. We installed a Dickenson Antarctic free standing
furnace. It was
a special order as we wanted 3 coils built inside it for hot water. We
then installed a
Webasto hot water furnace and piggy backed it into the Dickenson. If
the Dickenson
cannot keep up with the demand on cold winter nights, the Webasto
kicks in and
runs for 5-10 minutes and brings the water up to 140 degrees. It then
shuts down. 4
Red Dot units work on thermostats as needed.
We also added 2 dehumidifiers, although we only run 1 at a time. Our
rule of thumb
is if we get out of a hot shower and there isn't any fog on the
mirror, we turn the
dehumidifier off for two days. We then run it about 5-6 hours a day.
We have never
had any problems with mildew in the boat. On the contrary, we often
wake up with
dry or bloody noses as the boat gets too dry.
I can empathize with boaters with green shoes but feel there is no
excuse for them
on a boat large enough for a dehumidifier. We have one bought from
Sears before
they did away with their catalogue and one bought from J.C.Penny
since. They are
not expensive but necessary for comfortable living on a boat.
As I write this I am looking out of a starboard window at a light
drizzle. There is an
iceberg about 30 feet across against the next dock over from me and
some smaller
ones drifting down the channel. There is a male Stellar Sea Lion
(about 2,000
pounder) playing with a Dolly Varden about 100 feet away from us. He
has been
feeding here for about an hour. I am sitting at my computer in 72
degrees and about
20 percent humidity.
Life is good.
Eremite.
Originally posted November 7, 1996
We received a very informative article on winter condensation from
Darwin Boblet.
He covers the topic quite thoroughly and it should be of help to those
of us who
suffer from this problem.
Well, it's Late September and it's getting cool again at night. The
Fog has returned
and so has the humidity, so Let the Games Begin. Time to do something
about that
dreaded winter liveaboard problem, Humidity, Moisture, Condensation.
For that
reason I reopen this worn out, but never old topic.
First the Physics lesson:
Warmer air rises.
Warm air holds more moisture than cold.
Cold surfaces have cold air around them at the surface.
Warm wet air that comes into contact with the cold surface, cools and
must give up
some of it's moisture.
The result is condensation, wet surfaces, mold, mildew, etc.
Now here are some things I've tried, and my comments (look out!)
Dehumidifier:
The unit I'm using is designed for the boating environment with a nice
stainless steel
case and a drain hole instead of a catch pan. It cost about $300. In
the winter, you
can usually find more economical house hold versions that work just as
well,
perhaps better, that are cheaper, in places like Sears. These units
are usually
larger, and have an integrated catch pan to hold the water.
They work much like an air conditioner. There is a fan to move the
air, and a coil
which is cooled by pumping coolant through it. There is also a
radiator to dump the
heat removed from the cooled coil. Well designed, it will draw air
across the cooling
coils, then push the air past the warm radiator coils which re-warms
the air and
cools the radiator. The output air is a bit cooler (IMO) than the
input air ... but not by
much. The moisture condenses on the cooled coil and drips off ...
unless the coil is
realllllly cold, in which case it might freeze. For this reason, many
units will have a
timer that pumps room temp air over the inactive coil for a few
minutes before the
pump comes on and cools. The warm air will aid in melting any ice that
may have
formed. You might ask, isn't the ice cold, why won't it work as well
as the coil? The
answer is yes, but, the ice blocks the air flow between the coils
(look out, some units
have the coils too close together and you may have to modify them by
separating
the coils slightly like I did).
In practice, the do remove massive amounts of moisture, but every time
you wash
dishes, cook, breath, you put more in the air. THIS moisture they can
seem to deal
with all right. What becomes a problem is when you open your boat to
leave, enter,
ventilate, or use the shower, and wash dishes. They can't de- humidify
the hole of the
outside world and running hot water puts an amazing amount of moisture
in the air.
they can also be too efficient. They seem to work best when you are
sleeping or
away from your boat during the day. But they can remove enough
humidity to cause
wood boats to have the joinery separate (arghhhh!!!) or to cause
physical problem
like nose bleeds (it's true!). Keep the humidity about 60% and you
should have no
problem.
Heater and Furnaces
Remember the physics lesson. Warm air will hold more moisture. Keep it
warm and
it will not be as much of a problem as cooler air. Heaters and
furnaces can help
here.
Dry heat Vs Wet heat:
All heaters use fuel. Some burn alcohol, propane, diesel, or
electricity. If the heater
is vented, the heated air from the combustion, along with toxic gasses
like CO2 and
C0, will carry away the moisture that is in the fuel as well. The
heater or furnace gets
hot and heats the air around it. In a good system, perhaps there is
even a fan go
blow the heated air around and make it a bit more efficient. Most
heaters and
furnaces that burn liquid fuel have to contend with large amounts of
moisture in the
fuel itself. If you have a separate kerosene heater of the type sold
in many hardware
stores, designed for house hold use as a space heater, you will
generate so much
moisture you won't be able to keep up with it. The same is true for
putting a clay pot
on your stove and heating it. The clay stove heats the clay pot,
letting the pot radiate
lots of nice heat. But the stove burning it's fuel generates a lot of
moisture.
The best heat is dry heat, so go with a well vented system. Note
however, that if you
are dumping air up the stack as heated exhaust, you've got to replace
it with air
coming in the boat from somewhere, and that somewhere is outside moist
air. Kind
of a ketch 22 here, huh?
Electric heat provides a source of dry heat while at the dock.
Electric heat is dry but
has other problems. The main one is power consumption. I don't know
about you,
but I've got 50 amp supply power at the dock (at one time we had only
30 amps).
This power is variable depending on how many people at the marina are
drawing
power to heat their boats and the like. In the winter the voltage can
drop down below
105 volts, and the result is hot wires, blown breakers and the like.
Also, my boat
wasn't designed with lots of electric space heaters in mind, so
turning on a heater at
the end of the line can cause problems when someone has taken a shower
and the
electric water heater is on, while my wife try's to cook using the
microwave oven ....
then we still need to heat the aft cabin.... arghhhh!. The solution
for us was to
measure the power consumption of everything (interesting here that we
discovered
one of our heaters, the type that looks like an old radiator was wired
so that the Low
power setting was actually Medium power and vice-versa). We like this
heater the
best for keeping warm, but not for instant heat. Once you know the
power
consumption of all these things, you can make intelligent choices,
like, turning off the
water heater while you cook, or not heating the aft cabin while using
the little
ceramic heater and heating your water for the next guy taking his
shower. We also
installed an amp and volt meter to measure dockside power at all
times. It's nice to
know when the voltage drops, or we are pulling too much current.
Another type of heaters are forced air units for those that have the
money to spend.
These guys aren't cheap but can supply lots and lots of clean forced
dry air to your
entire boat. They run off of your boats 12v system and your diesel
fuel. Usually they
are located in a bilge area and use dedicated ducting to blow warm air
from one
side or your boat to the other while venting their exhaust outside.
One unit I've seen
also has a dedicated air intake line, so it adds no outside air to
your boat. We plan
to add one eventually. Now just where DID we put that lottery ticket?
So let's assume you've got the heat problem solved. Still have
problems ??
Lockers:
Many, perhaps most, lockers have a real problem. The problem is that
one side is
against the hull, and the hull is cold. Yikes, here we go again.
Someone once told
me that in the navy, every sailor is entitled to a 'hot' locker. The
hot locker is usually
dry and is not much more than a small space with a light bulb for
heat. I've tried it. My
problem is that we've got too many clothes, and the lockers are too
small. The
clothing blocks the air flow in the locker and the clothing against
the hull traps
moisture. The result is damp surfaces, and possibly damage to our
clothing.
I've tried the light bulb approach with limited success. Here's what I
did that seemed
to finally work. I used two pieces of 4" PVC pipe. One at each of two
opposite
corners of the locker, I positioned the pipe so it would go from about
10 inches shy
of the bottom to about 6 inches shy of the top. Then in one pipe only,
I put a small, 25
watt light bulb at the bottom of the pipe. Remember that hot air is
less dense than
cool air and will rise. The result is that the warm air from the bulb
flows up the pipe,
out the top, across the locker and down the other pipe (as it cools)
back to the
bottom where it is warmed again. The whole locker gets warm, and tends
to stay
dry.
Moisture Under the bunk:
yuck. It's amazing at how fast your mattress can mildew. Moisture
seems to flow
from your body at night and collect in pools under your bunk, against
the wood your
mattress rests on.
Here are some things I have tried:
heat the locker below. I've tried this with a small heater purchased
from West
Marine. No luck. I'm sure it helped keep the air warmer in the locker
under the bunk,
but didn't help much for the mattress. I think a light bulb would work
better.
drill holes in the board under the bunk. Hmmm, better, but not good
enough. This
DID seem to help in the spring and fall, but not the winter.
add some thin wood strips laced under the bunk to aid ventilation.
better, but my
design lacked enough air space. Later that winter I found the wood had
turned
moldy.
Another option might be to make a wood grating, much like the ones
found in
cockpit lockers. This might be more 'salty' but I don't have the time,
wood, or tools
for this, and I'm concerned that it would block access to the locker
under, which in
the case of the aft cabin, is also my access to the emergency tiller
control.
So there you have my two cents on the subject. I'm always looking for
good ideas,
especially cheap ones...
Darwin Boblet Dragon Lady.
*******************************
Bob Giddings
Dumbleton) wrote:
>Extracted from a web site -- some good stuf here:
>
>Pete
>
>************
>LiveAboard Magazine & Marine Chandlery
>Living With Winter
>
>
>The following is a compilation of various letters from boaters and how
>they have
>
>dealt with the problems of winter condensation and heat.
>
>
snip
Thanks, Pete. That was interesting. Is there a boat in your future?
Or does a Casita float?
Bob