some boats have dry interiors without the use of air conditioners/dehumidifiers and many others not so much. its not the brand of boat that is responsible for this, but its how someone has created ventilation to allow the moisture to escape.
if you have spent the money to buy a true dehumidifier or air conditioner, then you have bypassed any need for ventilation to allow the moisture to escape.
for the people that dont want to, or cant afford to spend that much money, ventilation is the absolute cheapest option to help dry the boat.
insuring there are no leaks to allow water in is the first thing that needs to be done, no matter if you use a dehumidifier/air conditioner, or just ventilation alone, the hull/caulking needs to prevent any water seepage into the interior of the boat to maintain a dry enviroment.
I was reading here and elsewhere, that some people seem to think there may be something wrong with their boat because its always damp inside, or that there is some magical formula to making it dry inside.
excess dampness inside is not an uncommon problem, but it should be because the fix is pretty easy compared to some of the other things we do to our boats.
and its not a secret... ANY boat can be dry if it has enough ventilation to allow the moisture to get out.
but even though the outside air will always be drier than the air inside the boat, in the natural environment, no amount of ventilation will ever be able to dry the space any drier than what the outside air is....
anyone who has the problem, and yet does not fully understand the problem, is going to be forever aggravated by it... and so are those that do understand the problem but do nothing about it.... talking, worrying, wondering and complaining about it wont ever dry the boat out.
basically, their are only 2 reasons for a "wet" boat....
#1 is... the owner knows of and understands the problems (or not) but doesnt care. he/she feels the time/cost to repair it is not worth the investment.
#2 is.. the owner doesnt understand the reasons that the boat is always damp inside (yet would fix it if they knew what to do about it)
and there is a third reason which shouldnt even qualify, but it is the single biggest reason most boats have a moisture problem...
the owner has undoubtedly heard over and over many times that ventilation will help eliminate their problem. but they reject it as an option because it takes some effort on their part, and it may even be hard for them to believe something as simple and cheap as ventilation could cure such a destructive problem. so they buy a small device from a salesman that claims to "dehumidify", without understanding the basics of how a true dehumidifier actually works.
EDIT... see the links to the cheap "dehumidifiers" that I am referring to... a real dehumidifier, one that actually removes the moisture from the air and space is much different than what is shown in the links.
the ones shown here are being sold way too often to solve a damp problem in a boat, because they wont do it. these are just a few of what you may find available that is being sold as dehumidifiers
if you have a proper dehumidifier then you have paid dearly for it and dont have a Dampness problem... but just because it says on the package that it is a dehumidifier, doesnt mean it actually is..
link 1
link 2
link 3
link 4
as for damp boats and spaces, here are some absolute truths that may help some to understand the issue.
then you can go forth with very little cost, time or effort, relatively speaking, and fix the problem forever.
#1... even on a wet rainy day, when the heater is going in the closed up space of the boat, the air outside will always be drier than the air inside the boat. you NEED ventilation so the air can exchange.
#2... people install a cheap $50 "dehumidifier" or heater to dry the space out, but these items only help to evaporate the moisture into the air.
#3... there is only so much moisture the air can hold at any given temperture, and if there is no ventilation so that warm wet air can not get out, it will contact the cooler surfaces of the boat and condensate into moisture... and the cycle begins again.
#4... people assume that heat is the answer to a dry boat. but it is NOT.... all you need is ventilation... and if there is air movement in the dampest areas, such as a small fan, it will multiply the effects of the ventilation....
#5... a fan, or other means of forced air movement is better for evaporating moisture from the boat surfaces than heat is. ALWAYS.
#6... warm air will hold a lot more moisture than cold air, so applying heat to the area will allow the air to carry more moisture out quicker, when there is adequate ventilation.
#7... because of fact #6, it is much easier and cheaper to have a dry boat in a cool northern environment than it is in the tropics.
#8... heat applied to a damp area without ventilation will cause mildew many times quicker than no heat at all in the same area.
#9... good ventilation in a damp area, with some air movement is very unlikely to grow mildew.... EXCEPT for the areas of the space that doesnt get the air movement, such as under a pillow or between the folds of a sail, ect.... any air movement especially without heat becomes a very harsh environment for the mold and mildew, and so it doesnt readily grow there.
#10... contrary to what the salesman of the small $50-$100 electric dehumidifiers want you to think, they DO NOT dehumidify. by definition, dehumidify would mean "removing the moisture"... all these units do is suspend the moisture in the air. its up to YOU to make sure the air gets removed from the space so drier outside air can take its place and absorb more moisture. this is called ventilation.
#11... any boat that continually has an influx of moisture from a hull crack, leaky deck fitting/rail, faulty fresh water fitting, hose or tank, ect. has a problem that will multiply the effort needed to dry it out.
the term multiply here does not mean twice as much effort, but it means many more times the effort.
#12... as inferred by #11, you must keep the bilge dry or you will need an excessive amount of ventilation while attempting to dry the boat out.
some of these points may seem a bit redundant, but so is repeating over and over and over in many threads by many people on many forums and sites, that you need some form of active ventilation (cheap)... OR a mechanical device (costly) that seperates the moisture from the air, and discards the water outside of the space.
hot climates only intensify the problem and the desire to fix it.
so if the boat happens to be located in a humid atmosphere, such as the SE coast, gulf coast, ect. where the air is hot and humid, these absolute facts still hold true, but because hot air can hold an excessive amount of moisture, even with excellent ventilation throughout the boat the air can still hold more moisture in it than we want to put up with, so a true dehumidifier will be needed to condition the air to the levels we are comfortable with.
there is no magical device that has ever been created in this world that can dry out an enclosed space unless it has a way to move the moisture to the outside of it.
ventilation is natures best way of doing this for us... but as man is always wanting more and better, along came Willis Carrier and invented/designed a mechanical device called the dehumidifier and hence the air conditioner, of which both work very well, but are much more complicated and expensive than the small cheap devices shown in the links above
if you have spent the money to buy a true dehumidifier or air conditioner, then you have bypassed any need for ventilation to allow the moisture to escape.
for the people that dont want to, or cant afford to spend that much money, ventilation is the absolute cheapest option to help dry the boat.
insuring there are no leaks to allow water in is the first thing that needs to be done, no matter if you use a dehumidifier/air conditioner, or just ventilation alone, the hull/caulking needs to prevent any water seepage into the interior of the boat to maintain a dry enviroment.
I was reading here and elsewhere, that some people seem to think there may be something wrong with their boat because its always damp inside, or that there is some magical formula to making it dry inside.
excess dampness inside is not an uncommon problem, but it should be because the fix is pretty easy compared to some of the other things we do to our boats.
and its not a secret... ANY boat can be dry if it has enough ventilation to allow the moisture to get out.
but even though the outside air will always be drier than the air inside the boat, in the natural environment, no amount of ventilation will ever be able to dry the space any drier than what the outside air is....
anyone who has the problem, and yet does not fully understand the problem, is going to be forever aggravated by it... and so are those that do understand the problem but do nothing about it.... talking, worrying, wondering and complaining about it wont ever dry the boat out.
basically, their are only 2 reasons for a "wet" boat....
#1 is... the owner knows of and understands the problems (or not) but doesnt care. he/she feels the time/cost to repair it is not worth the investment.
#2 is.. the owner doesnt understand the reasons that the boat is always damp inside (yet would fix it if they knew what to do about it)
and there is a third reason which shouldnt even qualify, but it is the single biggest reason most boats have a moisture problem...
the owner has undoubtedly heard over and over many times that ventilation will help eliminate their problem. but they reject it as an option because it takes some effort on their part, and it may even be hard for them to believe something as simple and cheap as ventilation could cure such a destructive problem. so they buy a small device from a salesman that claims to "dehumidify", without understanding the basics of how a true dehumidifier actually works.
EDIT... see the links to the cheap "dehumidifiers" that I am referring to... a real dehumidifier, one that actually removes the moisture from the air and space is much different than what is shown in the links.
the ones shown here are being sold way too often to solve a damp problem in a boat, because they wont do it. these are just a few of what you may find available that is being sold as dehumidifiers
if you have a proper dehumidifier then you have paid dearly for it and dont have a Dampness problem... but just because it says on the package that it is a dehumidifier, doesnt mean it actually is..
link 1
link 2
link 3
link 4
as for damp boats and spaces, here are some absolute truths that may help some to understand the issue.
then you can go forth with very little cost, time or effort, relatively speaking, and fix the problem forever.
#1... even on a wet rainy day, when the heater is going in the closed up space of the boat, the air outside will always be drier than the air inside the boat. you NEED ventilation so the air can exchange.
#2... people install a cheap $50 "dehumidifier" or heater to dry the space out, but these items only help to evaporate the moisture into the air.
#3... there is only so much moisture the air can hold at any given temperture, and if there is no ventilation so that warm wet air can not get out, it will contact the cooler surfaces of the boat and condensate into moisture... and the cycle begins again.
#4... people assume that heat is the answer to a dry boat. but it is NOT.... all you need is ventilation... and if there is air movement in the dampest areas, such as a small fan, it will multiply the effects of the ventilation....
#5... a fan, or other means of forced air movement is better for evaporating moisture from the boat surfaces than heat is. ALWAYS.
#6... warm air will hold a lot more moisture than cold air, so applying heat to the area will allow the air to carry more moisture out quicker, when there is adequate ventilation.
#7... because of fact #6, it is much easier and cheaper to have a dry boat in a cool northern environment than it is in the tropics.
#8... heat applied to a damp area without ventilation will cause mildew many times quicker than no heat at all in the same area.
#9... good ventilation in a damp area, with some air movement is very unlikely to grow mildew.... EXCEPT for the areas of the space that doesnt get the air movement, such as under a pillow or between the folds of a sail, ect.... any air movement especially without heat becomes a very harsh environment for the mold and mildew, and so it doesnt readily grow there.
#10... contrary to what the salesman of the small $50-$100 electric dehumidifiers want you to think, they DO NOT dehumidify. by definition, dehumidify would mean "removing the moisture"... all these units do is suspend the moisture in the air. its up to YOU to make sure the air gets removed from the space so drier outside air can take its place and absorb more moisture. this is called ventilation.
#11... any boat that continually has an influx of moisture from a hull crack, leaky deck fitting/rail, faulty fresh water fitting, hose or tank, ect. has a problem that will multiply the effort needed to dry it out.
the term multiply here does not mean twice as much effort, but it means many more times the effort.
#12... as inferred by #11, you must keep the bilge dry or you will need an excessive amount of ventilation while attempting to dry the boat out.
some of these points may seem a bit redundant, but so is repeating over and over and over in many threads by many people on many forums and sites, that you need some form of active ventilation (cheap)... OR a mechanical device (costly) that seperates the moisture from the air, and discards the water outside of the space.
hot climates only intensify the problem and the desire to fix it.
so if the boat happens to be located in a humid atmosphere, such as the SE coast, gulf coast, ect. where the air is hot and humid, these absolute facts still hold true, but because hot air can hold an excessive amount of moisture, even with excellent ventilation throughout the boat the air can still hold more moisture in it than we want to put up with, so a true dehumidifier will be needed to condition the air to the levels we are comfortable with.
there is no magical device that has ever been created in this world that can dry out an enclosed space unless it has a way to move the moisture to the outside of it.
ventilation is natures best way of doing this for us... but as man is always wanting more and better, along came Willis Carrier and invented/designed a mechanical device called the dehumidifier and hence the air conditioner, of which both work very well, but are much more complicated and expensive than the small cheap devices shown in the links above
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