How do you keep your boat cooler without AC?

[Tetepare]

Originally Posted by Olly75

Wet the decks down, evaporatitve cooling is a powerful thing.

Absolutely! This will make a marked difference. I do it just around dusk when the sun won't be burning up the deck anymore. Think of the radiant energy stored in a cored deck. Water on deck will cool it to begin with and the evaporative cooling affect is doubly effective.

[dennismenace111]

Dont cook down below... use a gas grill or stove on the aft rail.... heat from the galley stove takes a long time to dissapate...

[UNCIVILIZED]

Dual awnings rock! One for forward of the mast, all the way to the headstay. And then a standard one, from the mast to the backstay/runners. With removable, & or, mesh, side curtains if you can manage it. Keeps the boat out of the direct sun, which is big.

Aside from that, good natural ventillation. AKA use the breeze to your advantage for it's cooling effects, as well as to keep away the bugs. Since bug screens are a hugh hit against good ventillation.

Large dorade box structures are nice. One's which support 2+ vents per side. As seen on most of the Dashew's boats, & a few other production designs. And given the size (& thus drainage) of such structures, it's super rare to have to seal things off vs. water trying to enter the boat. A grand thing.

Next would be white decks, & light colored hulls. When in doubt use Ann & Jim Cate's trick of measuring the temps of various colors when they're out in direct noonday sun, prior to paiinting your boat with them. As just a tiny bit darker in some colors makes a gigantic difference.

And when all else fails. A BIG pitcher of ice cold (or even room temp.) Sangria goes a long way to making things bearable. Besides it's yummy! And it'll make you popular to boot

PS: One other biggie is to choose your linens wisely. As some styles, & materials are much, much cooler tactilely than others. Even others of the same weight. Though my cloth vocabulary's too lean to explain as to the why. Someone else can chime in on this perhaps?
And it's worth checking to see if Under Armor makes sheets. I'll surely buy'em if I head someplace where it gets stupid hot.

[Mystktravler]

Proceed immediately to N40 latitude and stay there...

[EmeraldCoastSailor]

I realize it is only applicable when on shore power in the slip but I bought a generic de-humidifier at Home Depot last year and run it while I am away and the boat is locked up with hatches closed. It seems to have made a nice difference in comfort level when I return to the boat.

In TX I used a solution from this company to keep the heat off:
Shadetree Boat Awning Systems | Shadetree Boat Awning Systems
It is a bit a of pain to put up and take down but once I got the process down it wasn't too bad. I didn't take it apart for day sails as it laid well enough with poles in place on the side deck while sailing. I still have it but haven't used it in FL yet.

[jrbogie]

Originally Posted by StuM

That doesn't work in half the world

not true. it does work in half the world. oh wait. never mind.

[MerlinBrasil]

Misters can be very effective and easy to DIY.

[S/V Alchemy]

Originally Posted by captainwireman

Blistering sunlight and high humidity make for an uncomfortable situation. Fans make a huge difference. Any other thoughts on this subject?

Windscoops, custom-sewn screens and a riding sail to keep you pointed into the wind at anchor. If it's brutally hot, awnings over the boom to yield shade and learn to duck. And swim. And enough batteries to make ice.

[barnakiel]

We use no fans but I think they are probably great. Plain PC stuff should work well.

All our boat is covered with sunbrella tents and all hatches are wide open. Never any issues with excessive heat (unless deep in the tropics and a calm day). Boat is grp with cored cabin and deck. White gelco deck, no teak.

Cheers,
b.

[Scott Berg]

Latitude

[powsmias]

Originally Posted by Copacabana

Yes.
1) Paint all horizontal (and vertical) surfaces white (even an off-white deck heats up horribly under the sun).
2) Use awnings during the day to keep the sun off the whole deck.
3) Improve ventilation aboard (more opening hatches, wind scoops etc.)
4) Have a way to keep everything open when it rains without water getting in.
5) Fans can help to move air, but they are a last resort.

New to this and pretty good theory.. anchor from stern and let dodger and bimini act as wind scoop and get breeze in cockpit as well.. thoughts?

[accomplice]

Originally Posted by Tetepare

Absolutely! This will make a marked difference. I do it just around dusk when the sun won't be burning up the deck anymore. Think of the radiant energy stored in a cored deck. Water on deck will cool it to begin with and the evaporative cooling affect is doubly effective.

Yes!

When it gets hot below we washdown the (teak) decks with seawater -- not only makes them much more comfortable to walk on, but also cools the interior noticably. When the decks dry in a half hour or so, rinse and repeat.

[JPA Cate]

Powsmias,

If your dodger has an opening "window" (ours simply unzips, and we roll it up and secure), anchoring by the bow does a better job of cooling the whole boat. With the forehatch open, and particularly with a scoop on it, the cool air moves from forward and exits from openings aft. Fans are placed so as to help cool the people when they sweat.

For those interested, there have been past threads about which fans & why. A CF Google Custom Search (under the Search menu) should get you there.

Ann

[buzzstar]

Originally Posted by Olly75

Wet the decks down, evaporatitve cooling is a powerful thing.

Good idea, do you have or have you used a system to accomplish this, particularly under sail and while in the hotter, even more humid locations than your home area. Southern California (my home area) can become very hot, but typically has relatively dry air (no pun) so evaporation works well (some outdoor restaurants even provide a fine mist to cool the area, including the patrons). Rain does not count, and sometimes contributes to the discomfort in the form of humidity. Acclimatization, as mentioned by Ann T. Cate, does help, but during the interim, only a bit.

[Kudawudashuda]

Shade cloth rolled down from your awnings is fantastic- albeit somewhat ugly. Breezes can blow through without significantly impairing visibility; easily rolled up out of the way; can be used under way; and very cheap.
Also a few cheap spray bottles at hand make a huge difference.
And sleeping on a damp towel will have you waking in the middle of the hottest night shivering.