Sailboat Ventilation

Sailboat Ventilation is the key to controlling mildew.

Keeping mold and mildew to a minimum in a closed up sailboat can be a big problem. Here is south Florida mold and alga can grow overnight and in a closed up boat it can get out of control in just a day or two.

Just by opening the boat up and letting air blow through can do a lot to keep mold down.  When I open the boat up I put an air scoop over the bow cabin hatch to help tunnel air through the boat, and it also will keep the cabin dry if a sudden sun shower accrues. We often get those down here in the afternoon. The scoop is just a canvas tarp that mounts to the rear of the hatch and with lines on the front side corners which are attached to the safety lines around the boat. It is not fancy but it works well and is quick to set up. It is surprising how much air can move through the boat with it. But if you are not able to do that every few days it does not help much.

A dehumidifier will also help if the boat is closed up. Our cheap dehumidifier will take about one to two Gallons of water a day out of the air inside the boat when it is closed up. This option requires a AC power source and being dock side for the power. A product like Damp Out will also help. You just have to empty the water from the collectors on both the dehumidifier or Damp Out regularly. 

I hooked up a vent fan, the type used for venting gas vapor when fueling, to our solar panel output so it runs automatically when the sun shines. These are relatively hi volume fans the can pull air through the boat. It also helps keep the boat interior cooler by venting the hot air when the cabin heats up from the sun. You need a voltage limiting circuit so you do not burn up the fan as a safety precaution.

If you do get mold growing on surfaces, you can clean them with house-hold ammonia and water. The Ammonia will kill the mold and mildew and it also stops many of the spores from being able to grow. Bleach and water also works well and the bleach will bleach out most of the stains. 

DO NOT USE AMMONIA AND BLEACH TOGETHER! It forms a poison gas. The gas would most likely kill the mold and any bugs in the boat and it could kill you. 

I will wash an area down with Ammonia and let it dry. Then I will wipe it down with bleach water and let it dry. Have good ventilation when doing both. The bleach residue left helps prevent new mold growth.

The easiest solution is to use your boat more often and that’s more fun. 8-)