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As I look over boats to consider buying, I see a number of boats from my wish list, that appear to be good possibilities, and in my price range. A number of them live up north and have hulls that are painted a beautiful dark navy, and some painted black.
While I love the look of a dark navy or black hull, I am more likely to spend my time in more tropical climates like the Caribbean or the Gulf. I'm worried about comfort in hot sunny weather. I've seen a number of people comment on here, saying that dark painted hulls heat up considerably more than white, making the interior uncomfortable. The cruising life could be ruined for my wife, if I can't make her comfortable.
Some boats have been recently painted, to prepare for selling them. I'd hate to destroy a perfectly good paint job, just to change color. If I could tolerate the dark color, until the boat needed refinishing, is it more difficult and expensive to go from dark to light, or is it a simple task of painting white over dark?
I want to factor the cost of repainting, if it's necessary, into my after-purchase upgrade and maintenance costs.
Questions:
1. How serious of a problem is a dark hull in warm climates?
2. What would be the expense of changing color on a 34 to 36 foot boat?
3. Is it a more involved job, and more expensive, to go from dark to White?
Questions:
1. How serious of a problem is a dark hull in warm climates?
Huge. I owned a green hull boat on Lake Huron MI, and even in the milder climate up there it got so hot that I painted it white. Our previous boat had black paint tying the cabin house windows together for a racy look. The boat was so hot in that area that it would burn your hand, and we kept a cover over it all the time in moderate to tropic climates. Our current boat now in wintertime FL (sun and 80F) has a black stripe on it. The hull is foam cored, but that black stripe inside the boat is so hot you can't put your hand on it. We have several friends with dark hulls in the tropics. Because their reefer/freezers are located on the hull side of their boats, they need to hang tarps on the side of their boats in this location just to give the reefer/freezer a chance.
2. What would be the expense of changing color on a 34 to 36 foot boat?
No idea. Pretty cheap if you do it yourself, very expensive if done by a professional in the US. A pretty good deal if done by a professional in some Latin American countries.
3. Is it a more involved job, and more expensive, to go from dark to White?
Doesn't matter much. Might take another finish coat to confidently make the transition. Prep and priming will be the same.
As above, the dark colored hulls do heat the boat's interior in the tropics, but touching the dark surface can also be a problem. I operated a dark blue steel sailing vessel in the Caribbean and it was extremely hot to the touch.
I have also read than unless a fiberglass boat comes off the production line as darkly painted it should not be painted dark. Apparently, again, this is something I read some years back and am not certain about, but there is a different finishing process in the layup for any hull that isn't to be painted white. Perhaps it has to do with the increased heat absorption?
The yard at the marina where I keep my boat has a really good reputation for paint work. A 36 ft boat done in awlgrip would run about $7000 just for topsides.
I would avoid getting a dark boat that has never been painted. Once painted, it will need to be re-done after a number of years. If you find a boat that has already been painted, and needs to be re-done, you may get a good price. Having a boat painted professionally is expensive. However, it is not exactly free to do it yourself. You will still be looking at maybe $1000 in supplies to do it yourself (and it is a lot of work).
I'm sure that a dark hull is warmer. How much warmer, I'm not sure. The top decks are going to be white, so we're solely talking about a few feet of topsides that are not well aligned with the sun and likely only one side is facing the sun. I've sailed aboard painted hulls in the Caribbean. They were medium blues, not the dark blues. Presumably, they should have been somewhat hotter, but I can't say I noticed. The Caribbean is hot. Indeed, that's part of the reason I go there.
I would not make this decision on heat. I simply would not buy a painted boat, unless I wanted a painted boat. Once painted, always painted. If it brings you joy, go for it. If not, it will bring pain. I do know an old marina neighbor how repainted his flag blue boat to white. No big deal. Same cost.
My wife has a unique position on this. She worries that fancy painted hulls will draw more attention in out of the way places, where one wouldn't want to appear to flaunt wealth. Not sure that's true, but it's something to think about. I think showing up in any private yacht of any color is going to flaunt wealth in some places.
I'm sure that a dark hull is warmer. How much warmer, I'm not sure. The top decks are going to be white, so we're solely talking about a few feet of topsides that are not well aligned with the sun and likely only one side is facing the sun. .
Some boats seem to look better with dark blue (and to some extent... other dark colors). It's a personal thing really. I do believe that they would act like heat sinks more than white hulls... just as teak decks are hotter than white gel/non skid.
Insulation and flow thru ventilation works to reduce interior heat.
The last time we had this argument here someone posted some actual figures as to the heat difference between a dark and a white hull. It really surprised me as to the quite significant effect.
Having had a summer in Grenada and time in Thailand and Malaysia where theres no Trade Winds I can tell you that it gets hot. Really hot.
Even with my 13 opening hatches and white hull and being at anchor, I remember that summer in Grenada well... I had to sleep with a wet towel on me for weeks at an end.
As the OP is heading to the tropics "I am more likely to spend my time in more tropical climates like the Caribbean or the Gulf" If its a choice you can make then you would be a dill to get a dark hull.
Also, for those that like the aesthetics of a coloured hull please remember that the only people who can see your pretty hull are not you. When you're on your boat you can't see it. When you're on shore you can only see a bobbing blob; and when you're in your dinghy leaving your boat you're looking forward; and when you are coming to your boat you're more worried about scratching the paint than the colour of it.
I think a black roof on a car would be more significant that dark sides on a boat. Just intuition.
As for aesthetics, I think you underestimate their significance to some. Looks at all the inefficient brighwork and spit and polish around most marinas. Boat maintenance will eventually get the best of any boater. The bills come in, parts on back order, etc, etc. It's trying. If you see your boat on the ride back from shore and she does that little something for you, it can make all the difference. For some boaters. Other just ride 'em hard and put them away wet. No right or wrong, but one approach will never understand what makes the other tick.
“White or the wrong color” according to the wizard of Bristol.
1. Heat
2. Fades quickly in the tropics and doesn’t restore to original color with common cleaning agents.
3. Any scratches or imperfections very obvious.
4. Repair requires large area or entire hull to color match as fade with aging will be different in new v old areas. This is true with white as well but much less obvious.
5. Dark v light areas will thermal expand/contract as different rates stressing underlying structures. More of an issue will metals but true to lesser extent in grp.
6. Additional expense. Even professionally done jobs may last no more than 5 years.
I just shot the black stripe on our boat outside. It is pretty cloudy today and there is no direct sun on it. The air temp is 86F.
The white hull is 96F.
The black stripe is 138F.
Inside the boat, that black stripe is outside a 1/2" foam core (and corresponding fiberglass skins), a 1/4" air gap, and 1/4" foam backed vinyl trim on 1/8" plywood.
I can't speak to the temperature difference between dark and light, but it would stand to reason that dark would absorb more energy.
I can say that dark boats can look great, but they also show every ding and scratch, and they tend to fade faster so dark gelcoat requires more maintenance to keep it looking good.
If you find a boat that you really like that is a dark colour gelcoat, don't let that put you off. You can have a vinyl wrap put on the boat for quite a bit less than a paint job. You can pick whatever colour (or pattern) you like and when the vinyl gets old and weathered it can be peeled off to reveal the nicely preserved gelcoat underneath.
The only real way to test this is with two identical boats, one painted and one not. Thermometer sitting in the salon, hatches open.
The air gap behind all the cabinetry on most boats is going to do alot of insulating, during sunlight hours, given the normal air exchange that takes place.
The only real way to test this is with two identical boats, one painted and one not. Thermometer sitting in the salon, hatches open.
The air gap behind all the cabinetry on most boats is going to do alot of insulating, during sunlight hours, given the normal air exchange that takes place.
I related my experience with the same boat colored green, then painted white. I don't have thermometer readings, but I do have several years living on it with both colors.
An air gap has no insulating properties at all. Once the heat is inside the boat, it is inside the boat. No boat is built so that the air in a gap between a cabinet and hull will get hot but stay only there and not radiate inward and throughout. No houses are designed this way. I don't know of anything designed with a free air gap as an insulating layer. Vacuum yes, insulation foam/fiberglass yes - but that works by preventing thermal movement of air across it, not free gaps.
The only way to stop the interior from heating is to prevent that heat from getting inside.
Above, I showed results of measurements of adjacent black and white surfaces on the same boat in the exact same place taken today through several layers of insulation, including through the hull's foam core and laminate, an air gap, a layer of plywood, and a dense interior foam covering.
One could hope that a constant exchange of air through hatches, etc will pull the hotter air out, but one would be massively disappointed in themselves when they reached sub-tropical temperatures, and would probably paint the boat when they got to the tropics.
It isn't a controversial point at all - it is proven, if not simply logical.
Had this very discussion with the fiberglass/paint tech at my yard. He said the dark hulls sometimes are too hot to even touch. White hulls not a problem.
IF and that's a big IF, you're going to stay in New England then yes, get the pretty dark hulled boat. South of there, NO.
A side thought around this subject: Pretty much everyone in the tropics eventually figures out some form of shade to put over their deck when at anchor. Those who have done this will attest to a 10F or more decrease in cabin temperature just from the sun no longer hitting a white deck.
Since we are on the subject of colors and heat, if you want the coolest sunbrella color for a bimini or shades, after several trials and errors we have determined that "cadet gray" is the color that is coolest. At first we thought darker was better, then we went light/white, then some tans, then cadet gray.
The dark ones are shadier, but very hot. Surprisingly, light/white was both light and hot - perhaps it was because it reflected IR light from the water well instead of absorbing it like a darker color would. We found that any color with red in it will get really hot, and that is why the tans didn't work well. Red is a great absorber of IR light.
Cadet gray has that sweet spot of no red in the color to absorb a lot of direct IR, dark enough to absorb reflected IR, and dark enough to ease the eye with shade.
Since we are on the subject of colors and heat, if you want the coolest sunbrella color for a bimini or shades, after several trials and errors we have determined that "cadet gray" is the color that is coolest. At first we thought darker was better, then we went light/white, then some tans, then cadet gray.
The dark ones are shadier, but very hot. Surprisingly, light/white was both light and hot - perhaps it was because it reflected IR light from the water well instead of absorbing it like a darker color would. We found that any color with red in it will get really hot, and that is why the tans didn't work well. Red is a great absorber of IR light.
Cadet gray has that sweet spot of no red in the color to absorb a lot of direct IR, dark enough to absorb reflected IR, and dark enough to ease the eye with shade.
Cored decks do help in the tropics. We have light tan non skid. Cored solid Bimini and hard dodger. All ports have shades. Hard dodger gets same treatment as sport fish use with white one way fabric as soon as the hook is down. White hull. AC is very rarely run for cooling and rarely for humidity. Mostly to put adequate load on genset when it’s gets its monthly exercise.
If you hate the white Clorox bottle look people have had good luck with very pale pastel colors. Seems yellow and very pale blue are ok as well as very pale grey particularly if metallic flack automobile paint is used but it’s expensive to keep up.
Of interest to keep yourself cool wear black if you’re going to be in the shade and white if you’re going to be in direct sunlight.
We’ve long since given up on sun tan lotion. Just sweats off or is washed off by spray when sailing. Wear shorts as legs see much less sun in the cockpit and +50 shirts with a bush hat. Have two sets of clothes. All synthetics including fast dry underwear for the tropics. Buy stuff on sale out of season. If you go the Caribbean good clothes are hard to find. Re up when you fly home for Xmas.
We don't go south and have had dark colored hulls on our last 2. And plenty of varnished teak. I know, not smart.
Even forgetting about the heat, this is the most costly way to own a boat in either maintenance time or dollars or both. Even up here, if you put your boat away in a shed (which you do when you are stupid enough to buy dark colored hulls and tons of teak which you need to work on all winter), dark hulls might make it 10 years before they requires repainting. A nice awl grip job is boat beautiful and unforgiving. Any imperfection in hull fairing looks like a fun house mirror, and any dock collisions even worse. Varnish barely makes a season even in my neighborhood and requires at least 2 top coats as well as build up coats anyplace it fails.
If I was headed south, there would be no doubt in my mind that I'd buy a white gel coated boat, no paint, with no teak at all above deck. If I was sensible, even living here, I'd do the same.
I've painted one of my trailerables. It was painted prior to me painting it, so it was "due."
Looked great. Was pretty hot below (sorry just anecdotal evidence).
I vowed since then to not own a painted fiberglass boat.
It was pretty stunning on the water when it was done (you know and new sails helped )
Yes it was painted white before, and I spent a season with it white before I painted it.
White gelcoat not only reflects heat better than dark colors, it also lasts a very long time. Our sailboat in the thumbnail is now 30 years old, with the glossy, original gelcoat still looking good (photo taken about 6 months ago.)
The best Sunbrella color for longevity is Pacific Blue. That said, we are happy with Toast Sunbrella. The Bimini and dodger canvas are one year old in the photo, whereas the sail cover is 23 years old. It is reasonably cool under the Toast Sunbrella, whereas the dark brown dodger on the power boat (Behind the sailboat) is noticeably hotter.
As I look over boats to consider buying, I see a number of boats from my wish list, that appear to be good possibilities, and in my price range. A number of them live up north and have hulls that are painted a beautiful dark navy, and some painted black.
While I love the look of a dark navy or black hull, I am more likely to spend my time in more tropical climates like the Caribbean or the Gulf. I'm worried about comfort in hot sunny weather. I've seen a number of people comment on here, saying that dark painted hulls heat up considerably more than white, making the interior uncomfortable. The cruising life could be ruined for my wife, if I can't make her comfortable.
Some boats have been recently painted, to prepare for selling them. I'd hate to destroy a perfectly good paint job, just to change color. If I could tolerate the dark color, until the boat needed refinishing, is it more difficult and expensive to go from dark to light, or is it a simple task of painting white over dark?
I want to factor the cost of repainting, if it's necessary, into my after-purchase upgrade and maintenance costs.
Questions:
1. How serious of a problem is a dark hull in warm climates?
2. What would be the expense of changing color on a 34 to 36 foot boat?
3. Is it a more involved job, and more expensive, to go from dark to White?
My hull is black. As I upgrade/replace canvas and interior cloth, they become black too. Is the boat hotter than my last white boat? A little on the side facing the sun. Judicious application of insulation on large areas that directly connect to the salon area have helped dramatically. Good ventilation is key. If I sat at a dock a good permanent HVAC system in the 15k-18k btu would be needed to stay alive on board. However, in cold climate traveling the hull and canvas becomes a collector of heat where there is not much to find. I've found myself cuddled up against the sun facing topsides many a morning. A little extra to deal with but man does she look good when clean. ?
A dark hull is not only hotter but can be dangerous in some light conditions.
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