When a fungal infestation--or anything else that similarly assaults our health--plagues any part of a living area, the knee-jerk reaction is to reach for the bleach. While bleach, a biocide, is quite capable of killing living organisms like mildew, it does not, the EPA reminds us, remove the organisms. Applying a solution of bleach and water to mildew will kill the mildew so it is no longer visible, but dead spores are just as threatening to the lungs, especially to those with weak respiratory systems. To remove mildew, simply scrub it with a stiff brush and a detergent and water solution and rinse with clean water. The Philadelphia Chapter of the Antique and Classic Boat Society recommends adding some baking soda to the mixture if you have especially tough mildew to remove. Use towels, fans and blow dryers to thoroughly dry the affected area.
When choosing a detergent, avoid using strong laundry detergents that contain phosphates, a delicacy for mildew. There are plenty of phosphate-free, natural laundry detergents on the market that will do the job admirably.
Remove absolutely everything that is infested and can be moved and place it in the sun for as long as you can. If the boat in question has a cabin, open all the curtains and windows and let in the light. If your boat has access to 110-volt AC power, set up a dehumidifier to soak up the moisture.
If the problem is so great that you need to refinish the interior, remember that high-gloss paint--preferably with anti-mildew agents--discourages mildew growth much better than flat or satin finishes, which invite it.
When you close up the boat for the winter, or even leave it idle for a week, take the time to clean every single place where mildew might grow. Remove pretty much everything that is not nailed down, that is currently wet or was wet at one point, and hang silica gel packets suspended in doubled nylon stockings in lockers, closets or anywhere else that gets especially moist or dark. As Acbsphl.org puts it, “When leaving your boat for more than a day or two, it should look as though it has been looted by professional thieves.” Encourage air circulation by opening everything you possibly can.
