Keep that inside air moving

I SUSPECT that a lot of boats down in the local marina will be bearing a heavy load of mold and mildew right now. We’ve had a lot of rain this past season and the inevitable drips from deck fittings have contributed to the kind of damp interiors that mold loves most dearly.

Because the outside air is so humid here in winter and spring, many boat owners think it only logical to seal the cabin tight so that no exterior air can get in. In addition, they will often leave a light bulb burning to take chill off the inside air.

But both these moves are wrong. Long ago, sailors and fishermen discovered that the two best defenses against mold, mildew, and dry rot are strong flows of fresh air and rock salt in the bilges.

Most amateur sailors would object to salt in the bilges, but the argument for good ventilation — no matter how damp the outside air may be — still holds strong.

The natural flow of air inside many sailboats is from aft forward, particularly if a main companionway dodger is fitted. So any intended ventilation should take advantage of this. If, for example you have Dorade boxes fore and aft, you might want to turn the forward cowls to face aft, so that they suck, rather than blow.  Similarly, the one nearer the stern should be turned to face the wind, so that they scoop wind into the cabin under pressure.

But not all boats are the same, of course, and I have had boats that demanded that the forward ventilators be turned toward the wind and the aft ones away from it.  Experiment with a smoldering joss stick inside the cabin to see what suits your boat best.  It doesn’t matter which way the air flows as long as there is a constant stream moving through.

Don’t ask me why mold doesn’t like moving air, even if it’s nicely damp and fairly warmish. I know it doesn’t make much sense, but it works. After all, sailing a boat doesn’t make much sense either. But it works, too, in its strange way.

Today’s Thought

The way of the Wind is a strange, wild way.

— Ingram Crockett, The Wind

Tailpiece

 “My uncle had an accident the other day and now he’s got a wooden leg.”

“That’s nothing. My sister got engaged the other day and now she’s got a cedar chest.”

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

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

Tailpiece

“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.)

Mildew in the forecast

WE’VE HAD THE MOST astonishingly good weather around here for the past couple of months, nothing but record-breaking stretches of cloudless skies and bright warm days. People can hardly believe this is the allegedly drizzly Pacific Northwest. It’s more like Southern California with the added bonus that it’s less crowded and less frenetic.

It can’t last forever, though. Sooner or later the rain will come, the grass will turn green again and the hibernating mildew (or, rather, the aestivating mildew) will get to work once more on our boats. They’re extraordinary little creatures, these mildew beasties. And they love dampness.

The tiny organisms we know as mildew or mold can eat almost anything anywhere, including your fiberglass boat. 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.

It also helps to 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.

So get ready. Mildew is in the forecast, and it’s very hungry. Act fast as soon as you spot any, on deck or down below, and be ruthless. Mildew takes no prisoners.

Today’s Thought

In wilderness I sense the miracle of life, and behind it our scientific accomplishments fade to trivia.
— Charles A. Lindbergh

Tailpiece  

Mary has a cool, cool gown,
It’s almost slit to bits.
Who gives a damn for Mary’s lamb
When we can see her calf?

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