Keeping the Cabin Cool

[msponer]

We really like greenhouse shade cloth. It's super durable, cheap, wind passes straight through it, and it doesn't capture air and then radiate heat downward like a solid material. So even though it doesn't block the sun completely (the 90% grade is more deep shade than total shade), the net effect is cooler. You can also use a double layer to get very close to total shade.

That it is moslty transparent to wind makes it a lot easier to use. You don't need to tie it down in a couple dozen places, it doesn't flop around and make noise or stress things, one can leave it up in all but extreme winds, and you can have side curtains without worrying about them catching the wind. It's also quick to cut and fit if you use the special plastic connectors: there's no need to hem or add gromets.

[TacomaSailor]

Crazy Cat said: "Okay not to dispute Bill the science guy and all you other geeks on here... but I live in Miami. My boat was blue I painted it white and it was cooler inside, sailed to Mexico it was hot put up a 20 dollar tarp for a sun shade and it kept sun off the top decks and it was even cooler. Get off the computer and go sailing!

Maybe he should read before he writes?

My first post said:

"What makes the biggest difference is the full boat awning that is installed and used every time you anchor. Especially important was the ability to tilt the awning to keep the rising and lowering sun from heating the cabin sides. "

AND showed a picture of the awning on my boat AND contained a link to a blog I wrote about the need for awnings.

Other posters said:
"The way to keep a boat comfortable is to keep the sun off the boat. Way more important is having awnings to block the sun entirely."

"As lots of other people have said, if you've got awnings then it doesn't make much difference because they block the sun"

[Sulaire]

+1 for greenhouse netting.

Works great and allows air flow as described. A full sun canopy for €30 !!

C.

[TacomaSailor]

We still use Sunbrella for the overhead awning but put up easily moved and shaped panels of greenhouse 90% mesh along the sunny side of the boat and around the cockpit as the sun gets lower in the sky.

We just use some heavy clothes pins to hang the material where we want it and then hang small weights off the bottom if the breeze is enough to make them flap.

It does work very well and lets the breeze thru.

[nimblemotors]

I put a black mesh over my outdoor work area during sacramento summer heat.
It is very effective at keeping it cool, and importantly does not get blown away if the wind picks up.

Who uses air conditioning on their boat? If I am spending a summer at anchor in Baja, the admiral is going to demand it, at least for sleeping quarters.
Are there low power options?

JackB

[s/v Jedi]

Originally Posted by nimblemotors

I put a black mesh over my outdoor work area during sacramento summer heat.
It is very effective at keeping it cool, and importantly does not get blown away if the wind picks up.

Who uses air conditioning on their boat? If I am spending a summer at anchor in Baja, the admiral is going to demand it, at least for sleeping quarters.
Are there low power options?

JackB

Run genset and run battery charger, watermaker and A/C at sundown (while cooking, time this) to take the heat of the day out of the boat. Then, when the sun is down and the heat is out of the boat, batteries topped off, water tanks at comfortable levels, shut it all down and use a fan for some air movement. We use a decent but small 110V fan instead of the garbage they sell for boats.

[TacomaSailor]

AirConditioning in the Baja Summer

BIG Caution - you will be the most popular boat in the anchorage or marina. EVERYTHING that requires gathering on a boat will occur on your boat. And, my experience is that boats that have AC also have ice makers so you will have constant visitors - bringing good scotch or gin&tonic water and offering it in trade for ice and cool conversation.

Six of us (boats I mean - about 10 people) hung out together for several years in the sea. Tackless II (a CSY 44 - Gwen and Don) had visitors at every hour of the day and night because they had a great AC system and a big ice maker and really big freezer (can you say I SCREAM?). They did enjoy the company and were prepared for it because they operated Tackless II as a dive charter boat in the Virgn Islands for seven years.

They ONLY used their AC in the late afternoon with the intent of getting the sleeping area down to 77 F or so by midnight. But - their main cabin was usually 10 degrees below outside ambient from cocktail hour to cruisers midnight (10 PM?)

BUT - the key observation about their AC system and life aboard. Whenever we gathered on Tackless II - we (sometimes a dozen of of us) would sit in their center cockpit under their hard dodger/canopy and surrounded by their 90% sun screen. We spent time below in the cool AC environment only about 10% of the time - usually when we were have "formal" dinners.

Once a week we had cooking competitions to see who could make the most outstanding "theme dish." We usually wore nice clothes and made a "civilized" meal of it - thus requiring the AC environment so we did not sweat on our silk shirts.

They had a very well insulated generator because I never heard it run despite spending hundreds of nights anchored within 50 yards of them.

[zeehag]

i will be learning about baja and golfo de california in summer this summer, as that is where i will be summering htis year-fr repairs and fun.
i have a feline of cold north gene pooling(maine coon mix)
i bought a 5000 btu air conditioner window unit in summer, 2011 because my gato didnt tolerate 110 f weather . mine fit into the huge formosa window in my dinette and with a fan to move the air to forward areas of boat, perfection, on lowest settings with tarps covering coach house and some deck spacing.
plastic tarps help keep the sun from baking the topsides and help improve circulation when placed for ventilation. when i had 3 layers of tarp in place, my interior was measurably 15 degrees cooler than out side on dock 5 in marina mazatlan, summer 2011. temps in july were 110+F......

oh yes, as i had my a/c on very lowest settings i kept it on all day and all night. my electric bill was negligible. my gato was happy camper.

[downunder]

[QUOTE=zeehag;

oh yes, as i had my a/c on very lowest settings i kept it on all day and all night. my electric bill was negligible. my gato was happy camper.[/QUOTE]

Expensive cat to run. demanding A/C.