August 6, 2013

Mildew in the overhead

A FRIEND OF MINE who keeps his boat in a sub-tropical climate recently removed the overhead in his thirty-footer. It was a disgusting mess, he said, full of old dead cockroaches and mildew.  Cockroaches, okay, but who would have thought mildew would thrive up there in the dark?

Well, I’ve said it many times before, but mildew can eat almost anything anywhere. These voracious fungi will actually slowly consume the gel coat on the deck of a boat under the right conditions, leaving it pitted and weakened. Down below, in dark, damp, stagnant air, they will reproduce at an astonishing rate, wreaking havoc on furnishings, sails, plastic fittings, and bulkheads alike. Mildew can even etch the glass in binoculars.

About the only thing mildew can’t digest is metal. On anything else, it excretes enzymes that convert complex molecules into soluble compounds capable of passing through its cell walls.

Mildew prefers sub-tropical conditions, but is highly adaptable to colder climates and actually creates its own warmth as it grows, leaving behind that typical musty smell.

Direct sunshine, dry air, and chlorine bleach are the best defenses against mildew. Most commercial mildew removers contain sodium hypochlorite (household bleach). But the best long-term protection is good air circulation throughout the boat to keep ambient humidity low. That means plenty of Dorade boxes, louvered drop boards, and solar-powered vents to keep air passing through and out of the boat.

One last tip: Open all locker doors and bilge hatches before you leave the boat for any amount of time, and prop up bunk mattresses so air can circulate underneath.

Today’s Thought
Nothing which we can imagine about Nature is incredible.
— Pliny the Elder, Natural History

“And is your punctuation good?” the editor asked a would-be cub reporter.
“Yes, sir, it is,” he said. “I’ve never been late for work in my life.”

(Drop by every Monday, Wednesday, Friday for a new Mainly about Boats column.)

1 comment:

Bill said...

I tell novices, or at least people more novice than me, that if you think you have a mildew problem, you don't.

You have a moisture problem.

Dry out the boat and the mildew will go away.