For many cruisers hailing from mild or cooler climates, such as northern Europe or North America, it can be difficult to imagine living on board in hot and humid weather. Yet tropical or warmer climes, including the Mediterranean, Caribbean and Pacific, are the most popular cruising grounds for sailors taking an extended cruise.

There are two major factors to consider when preparing to sail to hotter climates: first and most obvious is how to keep cool on board, and second is how the environment such as UV degradation, mould and mildew will affect your boat and its fittings and fixtures.

If buying a yacht specifically it’s important to keep shade, ventilation, and the effects of the sun and humidity in mind when boat shopping. When buying our Southerly 38, for example, my partner Nick and I took note of the relatively large number of opening hatches and specified a light-coloured hull.

We also chose not to fit side and foredecks with teak, not just because we didn’t want the maintenance but because we were concerned that the teak would be hotter underfoot than glassfibre.

Sail the Med

Australian couple Heather and Richard have spent the last three years sailing the Mediterranean with their two children (and blogging about their adventures on ayachtmoretolife.com). They purchased their 1989 Moody 425 in Spain and were initially concerned that because the Moody had been designed for the UK climate, it would be a struggle to keep cool onboard. But to their relief they have been comfortable on board even through very hot Mediterranean summers.

“The worst we experienced was 42°C in Zakinthos town quay [in Greece],” Heather says. “We sailed with friends who have a Beneteau 393 which has large non-opening hatches. These provide a lot of light but also make the boat very hot. I think any hatch in the cabin roof should be openable.”

Seathan and Audrie decided to opt for a catamaran for their circumnavigation despite being avid monohull sailors. They have two children and have spent the past three years sailing from Turkey, where they bought their Antares 44 Rehua, through the Mediterranean, across the Atlantic to the Caribbean, and then into the Pacific. After a summer in New Zealand they returned to the Pacific and thence to Indonesia, Malaysia and are currently in Thailand.

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They have spent a huge amount of time in the tropics, in both hemispheres and are very happy with their choice of boat. Audrie says: “The Antares is designed with maximum airflow in mind. There are so many hatches, including aft ones, making for good ventilation. All have mosquito nets and sunshades.

“We have air conditioning too: one in the main saloon, and one in each hull. But we hardly ever use it. We find it doesn’t help with acclimatising and we’d rather use fans.”

Air-conditioning is a luxury most cruisers won’t have, either because, as Audrie pointed out, it’s counter-productive in terms of acclimatisation, or because it’s simply too expensive to fit and too power-hungry to run.

Sometimes, however, desperate times call for desperate measures and if you’re lucky enough to have air conditioning on board it’s likely there will be times you’re grateful for it.

Audrie recalls that when they were in the Solomon Islands “there was not much wind at night and the heat was stifling. It’s the only time we regularly used our air conditioning. We would put it on for a few hours in the evening before going to bed to cool the boat down.”

After that, they bought portable 12V fans. “They are brilliant,” Audrie says. “At night they sit on the bedside table and in the daytime they keep us cool in the saloon where we do school or watch a movie at night. We wish we’d bought them sooner.”

Nick and I have also installed one on each side of the bed in the main cabin, another in the forecabin, and a third in the galley. We also have two portable USB fans that we keep in the saloon. In short we’re big fans of, well, our fans. Another popular item to keep the interior cool is a wind scoop.

Nick and I struggled to come up with a convenient solution for rigging ours, but after much fussing and experimenting we now rig it above the hatch in the forecabin, and attach it to the spinnaker halyard, which we secure with a line to the forestay.

With the main hatch and companionway open, this creates wonderful ventilation through the boat, although it’s no good at night as we lock the larger hatches and companionway for security reasons. Unfortunately winds scoops are far less effective in marinas, as the boat is rarely facing into the wind.

On-deck protection

A shaded cockpit is imperative. Not only does it keep the cockpit area cool and protect anyone in the cockpit from the sun, but it also keeps the inside of the boat cooler. Our main cabin is aft, directly underneath our aft cockpit, and so the bimini helps to keep the cabin at a more comfortable temperature.

Heather and Richard have a centre cockpit, which is shaded by a bimini, but they went a step further to protect the aft cabin. Heather says: “I made a cover for the rear deck that stretches from the solar arch to the bimini.

“We have gone through a few iterations of this but finally have a version that is robust and so far hasn’t got damaged in the wind. Unfortunately we can’t leave it up while sailing.”

Audrie created an extra sunshade for foredeck use while at anchor. She also brings up an important point for cruisers considering a catamaran: “It is critically important to have a shaded helm position. Many catamarans have a helm seat aft in the glaring sunshine. I don’t know how you would cope with that!”

In some climates sun glare is more of an issue than the heat. Heather and Richard recently shipped their boat from the Mediterranean to Australia and Heather notes: “The sun is much stronger in Australia compared to the Med due to the lack of ozone in the southern hemisphere.

“We could not survive without the shade structures in Australia but we tend not to need the fans as much here. The direct sunlight is unbearable but the air temperature can be lower than in Greece,” she says.

There is also a compromise to be made in terms of sun protection under way versus how easily visible the sails and wind indicators are. The wind instruments in the cockpit are far easier to glance at, and as a result we become reliant on these to a certain extent.

Last season our anemometer broke (a bird flew off with the wind vane clutched in its talons!) so we were without any digital wind readings for a couple of weeks until we got hold of the replacement part. This was a great opportunity to become more accustomed to reading the conditions without the aid of technology, but meant we were more often craning our heads around the bimini to evaluate the wind direction and assess the sail trim.

In cooler climates, we can always fold up the bimini or fold down the sprayhood for better visibility. We also have a window in the bimini to look at the mainsail.

Protecting fittings

Another key issue is UV degradation of your boat’s fittings, fixtures and equipment. Not only is this a nuisance in terms of maintenance, but it could be a serious safety concern. For example, a UV-damaged sail could blow out in inclement conditions.

Heather says: “Varnish and woodwork are the most vulnerable to UV damage. We opted not to go for teak decks partly because of this. Canvas covers help protect our hatches, but the canvas also degrades in the sun. We have gone through two safety horseshoes due to UV completely destroying the outer fabric. Plastic fittings also tend to degrade and become very brittle in the sun.”

Audrie adds: “The decks, sails, ropes, trampolines, bimini, lifeline netting, all the vinyl coverings, the gelcoat, the hatch seals, sunshades, fenders, anchor chain, running rigging, the dinghy… everything suffers!”

There are, however, many ways to prolong the life of your fittings and equipment. If you don’t have in-mast or in-boom furling, stowing your mainsail in its sail bag when you aren’t under way will prolong its life.

Dinghy chaps are an excellent way of protecting your dinghy from UV damage (learning to sew and having a sewing machine onboard can be a worthy investment of your time and money). Using high quality, UV-resistant canvas such as Sunbrella will prolong the life of your bimini, dodger and sprayhood, as well as your sail bags and various covers.

Cleaning and polishing also help to preserve your items. “We regularly rinse our running rigging lines and soak them in fabric softener, and also end-for-end them,” says Audrie.

Humidity issues

Mould and mildew is a problem in hot or humid climates, and of particular concern for cruisers such as Nick and myself who regularly leave our boat for prolonged periods to go home and visit family. Luckily for us, our boat doesn’t seem to ‘sweat’ much and we’ve only had issues with mildew in the bedding and clothes on our return. A thorough clean usually resolves this.

Prevention is preferable. The prevailing advice is to clean all surfaces on the inside of the boat with a solution made up of one part water and one part vinegar before shutting your boat down, which helps to prevent mould and mildew. We also put out moisture absorbing crystals throughout the boat to help absorb any moisture in the air.

These measures aren’t always effective against the unexpected, however. Heather and Richard store their boat every winter in the Mediterranean to go back to Australia.

Heather recalls: “We had a leak over last winter which meant that water collected below the engine and made the inside of the boat quite humid. We came back to a lot of mould on the woodwork and rust on the engine, [though] the mould wiped off easily and the rust was treatable.

“Being onboard often and staying on top of maintenance to ensure the boat doesn’t have any leaks is important to avoid mould.”

About the author

Terysa Vanderloo and her partner, Nick, are in their third year of sailing around the world on their Southerly 38 Ruby Rose and they produce regular videos on their trips.