How do you stop condensation on bare fiberglass?
1988 2520 condensation problem
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In short, you have to reduce/remove the moisture in the air and/or control the temperature of the 'condensing' surface; the fiberglass surface. Be thinking 'Glass of Ice Tea'; You pick up a glass of ice tea, your hand gets wet. It gets wet because the moisture in the air surrounding the glass has condensed, rained, sweated, reached dew-point, (all the same 'term') on the surface (actually, on the air-film) of the cold glass. It also is how all mechanical air-conditioners remove moisture from the air. The moisture in the air condenses on the cold coil, and the condensate water drips out of the unit... The Water-Air-Relationships are a 'perfect' science and are explained on the Psychrometric Chart (PCh) developed by Willis H Carrier (yes, that Mr Carrier). One basic item we need to understand is relative-humidity. Relative Humidity = The number of 'grains' of moisture in the air RELATIVE to the temperature of the air. You will change the relative humidity of any volume of air by raising or lowering the temperature of that air. (When you raise the temperature, you LOWER the relative humidity. When you lower the temperature, you RAISE the relative humidity). Using the PCh you can determine exactly what relative-humidity air will condense on a given temperature surface.
To manage moisture issues, you must be able to measure them. If you don't have access to a Sling-Psychrometer, buy a battery-operated one for $10.00 at a home center. Depending on where (the climate) your boat is will determine what steps are needed to control the moisture in the air, and/or the temperature of your fiberglass surface..... In summary, you have to warm/heat the surface and dehumidify the air that comes into contact with the surface.
By the way, this all also relates to mold and mildew issues on boats (or anywhere else mold takes place).
Think "The Fire Triangle". For fire to exist, three ingredients must be present; heat, oxygen, fuel. Get rid of ONE of the ingredients, then there is no fire..... With mold/mildew it is not a 'triangle' it is a pentagon. Five ingredients must be present for mold/mildew to exist. Oxygen, Mold Spores, Mold Food (which is anything organic), Temperatures above 40 degrees F and below 120 degrees F, And Moisture/water. Get rid of ONE ingredient and mold cannot exist. The only one of these ingredient that you have any prayer of eliminating is water/moisture!. And that is difficult on a boat.... Anytime there is water present and/or a Relative-Humidity of 70% or higher, it is not that you 'might have mold/mildew, you WILL have mold mildew, because all of the other 4 ingredients are already there..... You have to control the source of the moisture/water..... If any one is still reading all this, I will be shocked! ☺
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I keep side windows opened a little and I installed vents that fit into berth windows from Beckson. They keep rain out and allows air flow. In the cockpit, I used an old deck pie plate to install solar fan. When working it pulls air from.bilge, cabin and sides.. works better than I thought it would. My boat sits on a covered lift in Florida and don't know how or when you are having condensation issues.
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Hi Brent, you Floridians are very fortunate, because, well because it's warmer there! ☺ It's harder to find a cool/cold surface for condensation to form on in much of mid to south Florida!
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We love it. Where are you located? A regular fan on timer will work, too. Our boat still collects water in wheelhouse bilge and solar fans helps to dry it out if sunny. Opening hatches or doors helps too
Hi Brent, I'm on Pungo Creek in mid-eastern North Carolina, some call the 'Inner Banks'. We deal with four distinct seasons here; hot humid summers, short cold winters, and nice springs and falls. The best and worse of all worlds! ☺
When dealing with condensation and/or mold issues, fans and ventilation can help in some climates, site specific. When ventilation starts bringing in more of some of the 5 ingredients needed for mold growth, then it's often better to seal up and use mechanical or desiccant dehumidification, cleaning, dewatering, etc; it all depends on the conditions in a given location.... Warm air has the 'capacity' to hold multitudes more grains of moisture than cool/cold air. The Psychrometrics Chart shows all these air/water/relationships. It's why a hair dryer dries your hair better on the hot setting, than on the 'cool' setting. Hang a wet towel outside on a 90 degree day, and you see how much faster it dries compared to a 30-40 degree day. Wither ventilation helps or hurts is 'site' specific; in some mixed/moderate locations ventilation causes more harm than good..... In general, keeping all surfaces clean and dry, and the air below 70% (I use 60% as my baseline) relative humidity is the first line of defense...
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Thanks
I live on Prince of Wales Island in SE Alaska
Hi mb4570, Welcome to Classic Parker!.... My guess is you all have some severe/cold weather there on occasion? !! .... I've have on a dozen+ occasions been a 'few' miles south of there, from the Vancouver area to Whistler/Blackcomb.... you are in a beautiful area! Sea to Sky! One of the most beautiful roads I have been on!
Antidote
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I leave the side windows open about 2" and close the screens. I also hang a Damp Rid bag in the berth and change it out when it fills up.
sailmaster
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I saw a pair of Nicro/Fico (sp) Solar vents in a photo on this website on the large aft hatch
Those things work. Installed a pile of them in my past life on heads. We also used to drill vent holes in keel stepped masts to dry out bilge stank
need an inflo and an out flow. Nice thing with the NicroFicos is there is a flat plate that fills the hole when you are fishing
Those things work. Installed a pile of them in my past life on heads. We also used to drill vent holes in keel stepped masts to dry out bilge stank
need an inflo and an out flow. Nice thing with the NicroFicos is there is a flat plate that fills the hole when you are fishing
Hi Antidote, as you've witnessed, Damp Rid bags and/or containers collect moisture from the air, as desiccants (unlike dehumidifying by cooling/condensing). But their intended use is for small, enclosed, nearly air-tight closets/storage areas. And these areas are already inside a home where hopefully there is little moisture in the first place, and reducing and/or blocking the moisture source is easier.... Not the same as on a boat that is not heated and cooled like the home is. An area on an unconditioned boat, with the volume of space of the cuddy cabin and/or pilothouse would require a massive number of Damp Rid containers to make any meaningful reduction of the relative humidity of that space; especially so with the windows cracked. This can be proved by monitoring and measuring the relative humidity; I recommend getting one of the small electronic models (like AccuRite; $9.99) from a home-center. You could do your own experimentation that will show that Damp-Rid, (or any other type of desiccant), although collecting some moisture, are not 'powerful' enough to lower the relative humidity of that space, especially so with windows open/cracked. This is so because of 'vapor-pressure'. Vapor/moisture travels from an area of high-concentration (higher-humidity) to an area of low-concentration (lower-humidity). (Think of this as a 'sponging effect'; a dry sponge drawing in water). If we dry a volume of air, without reducing/preventing the source of the moisture, then we are making no progress in lowering the relative humidity. The more you dry it, the more of a 'sponge' it becomes. Trying to reduce relative humidity with windows open can't work unless the air outside is a lower relative humidity than the area you are trying to dry; I too lived in SC for a number of years, and best I remember, the outside air was often very humid! ☺
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Antidote
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Hey Andy I understand everything you said above and I don't disagree with you; but, considering I don't have a mold problem my system works. It may be becauseI keep the birth door and windows closed and the birth does stay dry. In the cabin I crack the windows because my fridge is always powered so it cycles on/off. Maybe that is enough of a heat source to keep the moisture down in the cabin. It may also have something to do with the boat being slipped in a locked harbour. The water temp in the harbour doesn't change dramatically so the hull doesn't heat and cool as much as it would on a trailer. I only change the Damp Rids about every 4-6 weeks and I buy the scented ones so the birth smells nice also.
sydngoose
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Been using Damp rid hanging "fresh scent" bags in my pilot house boats for 8 years: no problems with mold yet. I do like the dehumidifier idea, but also a fan of Accams razor and KISS: Keep It Simple Stupid.
Just bought another 3 pack of damp rids yesterday. Good for another 3 months...
Just bought another 3 pack of damp rids yesterday. Good for another 3 months...
what is best material for insulating 1988 2520 pilot house ?
Hi mb4570, I just now saw your post here. It's a great question, and I hope I can shed some light on a solution, or why there is no great solution. I'm sorry this is so long, but I didn't have time to write a short explanation. (I did not invent that saying!).
To start, the biggest issue with trying to insulate something like a pilothouse is that there's not much room/space to do it in/on. And no great way to apply insulations to fiberglass, And even when doing so, it's hard to apply a protective barrier/layer over the insulation to protect it from damage. (With that said, foams, because of their high R-Value to thickness ratio, will likely be the best (only?) option).
Here's some basics to get started:
To retard air-related heat-flow, there is only one insulation on earth, and that insulation is 'Air' itself. All insulation products become 'insulation' by trapping gud-zillions (a slight-exaggeration) of tiny, microscopic, air pockets. (That is how fiberglass, rockwool, vermiculite, perlite, air-crete, and all four commonly used 'foams' etc, become an insulation; they trap gud-zillions (a slight exaggeration, again!) of air-pockets. (By the way, what I'm describing here has nothing to do with 'insulation' on electric-wires, nor 'insulation' like asbestos that used to be used on ships, and in industry, nor the tiles on the the Space Shuttle that insulate/prevent the shuttle from melting on reentry; that's a different science. I can explain them, but they're not useful to this conversation).
When talking insulation we have to understand a couple basic terms; U-Value, R-Value, Conduction, Convection and Radiation (The three ways heat is transferred from any 'point-A to point-B'). What came first, 'The Chicken or the Egg?' (I don't know). What came first, U-Value or R-Value. (I know that one!). U-Value came first; it's the number of Btu's (the unit we measure heat with), that can pass through a square foot of 'given' material, by conduction or radiation, dependent on the Delta-T (Temperature difference) on either side of the material. The problem with U-Value, is that they're hard to understand, and that they are Darn-Right-Un-American! With U-Values, the smaller the number/amount the better it is! And it's almost always going to be expressed in a decimal. (.037, .045, .687), a lot of people don't understand 'decimals', and they sure don't understand something being smaller as being better! ☺ So that is where R-Value was invented. It was invented so the average person can understand heat-flow; or better stated, the prevention/retarding of heat-flow. Once we measure and/or determine U-Value, we invert/use the 'reciprocal' number. (1 divided-by). For example, if the U-Value is .044, one divided by .044 = 22.72 The R-Value is 22.72. AND the bigger the number the better the insulation factor. (see, we can understand that).
So, how much insulation do we need to make a 'measurable' difference? The answer is at least an R-4, but better yet, about R-7 to R-9. That is where the initial, largest percentage, best bang-for-the-buck benefit occurs. Beyond this, the law-of-diminishing-return kicks in; Yes, in our homes typically R-38+ ceilings, R-22+ walls, and R-19 floors will suffice (these numbers are totally climate-dependent! And you'd have to read my book on that; it's not a subject for a boating forum!) But in our boats, to add some level of comfort, and/or to help slow down condensation, even R-4 to R-5 can help. (depends on the temperature and relative humidity of where the boat is).
How can we achieve this? Only with foams. Polyisocyanurate, (foil-faced for reflective properties and to hold in the gasses as it cures), Extruded Polystyrene, (the blue, green and pink boards), Expanded bead polystyrene (the white 'coffee-cup crap), and Urethanes, the 'yellow-ish' foams. (must be sprayed on with special training, and special equipment; and is very hard to get a smooth, even, consistent finish.
To use most foams, you would have to remove the Parker-Carpet, and glue the sheet-foams to the fiberglass, and hope the glue is strong enough to hold it in place without first melting the foam! That's the easy part. The hard part is that these foams are fragile, and easily damaged. They need a protective covering. How do you install any known type of protective covering? Vinyl? Okoum? Thin plywood? A heavy coat of paint? Like I mentioned, that's the hard part...
How about 'bubble-pack'. The 'bubble-pack' industry is one of the most sued industries in the country. Sued for miss-representing their R-Values, U-Values, K-Values, and heat-reflective values, and "Radiant" values. They were even sued by NASA for lying about NASA!! Bubble-pack has a place here on earth, but not for insulating a boat, or house....
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Thanks for the reply, this the first Parker boat I've every been around so don't know much about it but I like the style, this 1988 2520 Sou'Wester is no frill's just bare fiberglass in the house so I don't need to remove anything to insulate, just trying to avoid trial & error as much as possible. I live on Prince of Wales Island in SE Alaska so not a lot of expertise around regarding Parker boats 
I want to keep this boat as nice as possible its very clean and well kept, the previous owners kept this boat in doors and only used it 3 weeks a summer when they came up to fish so its still a very nice boat. Again thanks for the reply and I'm very amazed at the CP forum it is a wealth of information backed by experienced boaters that share their knowledge freely and definitely love their Parker Boats ! Thanks
I want to keep this boat as nice as possible its very clean and well kept, the previous owners kept this boat in doors and only used it 3 weeks a summer when they came up to fish so its still a very nice boat. Again thanks for the reply and I'm very amazed at the CP forum it is a wealth of information backed by experienced boaters that share their knowledge freely and definitely love their Parker Boats ! Thanks You are welcome; I hope I was at least a little help....Thanks for the reply, this the first Parker boat I've every been around so don't know much about it but I like the style, this 1988 2520 Sou'Wester is no frill's just bare fiberglass in the house so I don't need to remove anything to insulate, just trying to avoid trial & error as much as possible. I live on Prince of Wales Island in SE Alaska so not a lot of expertise around regarding Parker boats
Wow! I hear Prince Wales Island is a beautiful place; and likely a perfect place to have a Parker pilothouse boat! The 1988 Sou'Wester is one of the early versions, and it's been a long time since I've seen one. I'm sure there is a lot of information on them here on CP....
GotChrist?
Well-known member
I run a dehumidifier, but the boat is stored in my backyard. If wet slipped and had shore power available, it could still run, just would be a PITA to run with it bouncing around. Forget the small lunchbox sized ones. They don't pull enough. I have a full sized one. It's heavy, but cabin remains moisture and mildew free. Plumb the drain hose so it can flow freely out of the boat. You don't want to crawl into the boat once or twice a day to empty it.
