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March 16, 2006 - Ventilation
by Al & Beth Liggett

Keeping a good air flow through the boat is absolutely essential in the tropics for several reasons. Personal comfort is the main one, but keeping mold and mildew from developing is high on the list too. Also, boats that are closed up smell – be it from fuels, engines, toilets, drains, shoes, cooking, whatever.

Every boat has its own requirements for ventilation, some more practical than others. The installation of hatches, opening ports, and dorades is usually fixed with the building of the boat. If these seem to provide inadequate ventilation, it would be advisable, but not always easy or practical, to add more.

Sunflower has two large hatches on the foredeck. One is over the workshop in the forepeak; the other is over the passageway right beside our double bed. We have six opening ports – three on either side of the low cabin top. These feed air and light into the galley and the chart table area. There are three dorades located on boxes – two on the forward end of the main salon port and starboard, and one centered on the forward part of the cabin top. We installed another one on the deck over the bed a long time ago, but found it to be a real nuisance when stowing the dinghy there. So we took it out and filled in the deck hole. All of these – hatches, ports and dorades - when open, provide us with our basic air flow needs. We use screens on all when we are in buggy conditions. Screens do restrict a certain amount of air, however.

To augment these openings, as well as to get some air when the breezes stop or the rain descends, we also have a bunch of 12-volt fans. Last time I counted there were nine fans on board! Well, we only actively use five of them. Three of these are Hella fans. We have two Hella 2-speed fans up forward: one over the work bench, and another at the foot of our bed. They take very little power and are pretty quiet. The third is in the galley. It is 1-speed, can swivel toward the main salon, or fold up toward the ceiling, which is good. But it is a noisy beast! Hella fans are hard to take apart to clean, and don't have a reputation for longevity. However, Al knows how to fix them by replacing the brushes in the motor. He is always on the lookout for tiny electrical brushes.

Making biscotti before Christmas. It was raining, so the opening ports are closed. You can see my galley fan in the right side by the curved bulkhead.

The fan over the chart table is a computer fan. It draws less than an amp, is a little noisy, but really pumps out a good bit of air.

The first fan we bought for the boat – in the Philippines in 1977 – is still going strong! It is just a 12V car fan, easy to clean, draws 1.3 amps. We have it mounted on a round wooden base with a cord long enough to reach half the boat from one of our 12V outlets. This portable fan normally lives under the table, keeping us cool in the main salon. But it is really useful for times when Al is working on the engine, or is back under the cockpit struggling with something, or if we just need more air than our other fans can deliver, or air into places they can't reach. For that reason it is also good for drying out paint or varnish projects quickly, or for disbursing fumes from the same.

Many people use a fabric wind scoop over a hatch to gather the wind more forcefully below. We used to have one for the hatch over our bed. But we found that with our large expanse of foredeck we really needed to have an awning to help keep the deck cool. Our deck awning stretches from the staysail stay back to the mast. We found that the peak in the front actually acts as an effective air scoop, sending air down the hatch beside the bed. Because this awning is a PVC material, we can leave that hatch open in all but the heaviest of rains.

The dodger has a zipper on the middle window, which we roll up to bring the air from across the deck into the cockpit. Depending on our anchorage, we often need to stretch a piece of awning across the back of our main awning to deflect the sun from shining too brightly into the cockpit and down the hatch. This aft awning also acts as a wind scoop of sorts. There is a definite backdraft flowing off the inside and into the cockpit.

So why not just have an air conditioner? Well, many boats do. They require a good deal of power however. If you need to use it at an anchorage, you will have to have a generator to supply the power. Therefore, most boats with air-con usually only use them while in a marina berth where they can plug directly in to electricity. Some boats seem to cruise from plug-in to plug-in for their air conditioners.

Some of the marinas in Malaysia and Thailand are well protected, but very HOT. We've done our share of sweltering in them! And seen the liveaboards there turn to cooling their boats with air conditioners. I used to say (striking a pose with hands firmly on hips) "the day I need an air conditioner on my boat is the day I will forget about cruising." Well - words I have long since eaten!

We were in Rebak Marina when we changed the engine in 2003. A friend loaned us their spare air-con. What a blessing to do all that interior work with some relative comfort. The following year we again had mega paint and varnish projects below, plus the Mother of all Haul Outs to deal with. We bought our own air conditioner. It REALLY made a difference to our comfort and sanity. But it was hard to stow below while sailing, and with plans to sail out to Chagos in 2005, we sold it. And have not missed it.

Well, now I think I'll turn off this noisy fan and retire to the breezy cockpit with a lemonade, my latest book, and the binoculars so I can see what's going on around us in the anchorage.