Ventilation - Tips & Tricks

Tim Good

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Ok so I have the usual vents in the washboards. However, the best ventilation comes from a draft. I.e. when you leave the front hatch open and allow a breeze to run through.

However, I can't leave my hatch slightly ajar for fear of rain coming in or security.

Anyone come up with an ingenious solution for getting a draft going without compromising on the above?
 
Are you sure your hatch doesn't have a vent setting? Most modern ones have two plates for the latches to grip. If you use the lower ones, the hatch is completely closed (normal setting) but if you open it slightly and guide the latches into the gap between the plates, they will grip the upper set and hold the hatch slightly ajar. The hatch can be locked in this position as normal. It may let a little rain in when the wind is blowing in the wrong direction but not seriously. You could perhaps stand a block of wood on deck next to the hatch (a couple of inches away from it) to block most of the wind-blown rain.

Not much help if you have the sort of custom fibreglass hatch used on old boats, of course.

Pete
 
I have built a large vented box which fits over the whole of the forehatch and allows it to be opened to about 30deg. It is secured from below by rope and a strongback, across the opening. It works very well.

The boat is also fitted with snug fitting cockpit cover and I am convinced keeping the cockpit dry helps the cabin and promotes good ventilation. I have a cover for winter and summer use - it also helps, a little perhaps, to deter lightfingered visitors and keeps the cockpit clean. I leave cockpit lockers cracked open a few degrees with a bit of rag.

In the cabin I open all lockers, remove most books, fabrics and some cushions. Cushions not removed I prop vertically in an open area. I shift and wash any wet ropes and canvas items in the cockpit lockers before replacing them freshwater dry. At some stage over the winter I sponge most of the hull with disintectant/anti mould stuff.

I have never been troubled much by residual condensation and only put a 40 watt bulb under the engine (on a timer) during the worst of winter cold snaps.
 
The hatch can be locked in this position as normal. It may let a little rain in when the wind is blowing in the wrong direction but not seriously.

Yeah it does but I tired that when it was tipping it down once when I was stuck in Falmouth for a few days and water did come in. I should probably check this again and ensure the seals are seated correctly. As you say a bit of rain coming in probably offsets the benefits of extra ventilation.
 
I have built a large vented box which fits over the whole of the forehatch and allows it to be opened to about 30deg. It is secured from below by rope and a strongback, across the opening. It works very well.

Ooh, good idea, I like it. I've got a load of surplus OSB board and could easily knock up something ugly but effective. Some kind of dorade-style idea to keep the rain out while letting lots of wind blow through.

I already have a winter washboard with a big hooded vent built into it, which is something else for the OP to try.

Pete
 
The bow and the stern.

On our current yacht we found mould occuring inthe foward cabin and in the quarter berth no matter how much ventilation we introduced via the hatch or the deck vents. I then introduced a standard PVC flexable vent into the chain locker and another into the very sten of the boat on the deck. They both have screw on covers if we are worried in bad weather at sea and want them water tight. That was about 10 years ago, since then no mould and we have never had to put on the covers desoite some bad seas. The yacht is a 34ft Van de Stadt Legend. Ventilation should be over the full length of the hull!
 
How about cutting a hole in the hatch and fitting a ventilator into it? Obviously it would have to be a type that can be completely closed at sea and won't break when trodden on.
 
I'm not sure if you are afloat or ashore. When laid up ashore I remove the plug from the through-hull for the log impeller and remove the tapered body from the heads outlet seacock. Holes in the bottom of the boat permit ventilation but don't let the rain in.
 
You don't say what sort of boat you have, but I would think a washboard grille and a forehatch is not enough. You should consider putting some extra vents in the deck somewhere forward. Ideally dorade vents, but a variety of vents available.

We have one in the forepeak with a small plastic 'funnel' on deck. It doesn't create a great flow, but it's continuous, never lets rain in, has an anti-insect mesh, and has a flap that is supposed to close if you get solid water over the deck.

We also have a 5" bronze dome vent in the saloon (you can also get 3" ones), above the cooker. This screws right up to provide a real draught, can be left slightly open still with significant draught but rain doesn't come in, or screwed completely shut if its rough and danger of green water over the boat.

We have another vent in the head compartment which is just a circular hole in the cabin roof with a BIG 'funnel' outside. This can be closed by pulling off the funnel and putting a cover on, but as it's under the sprayhood we can just turn the funnel opening forward to stop any rain or spray getting in.

Any of these, or other types, would improve your situation. You can't have too much ventilation. (We have these three, plus vents in the companionway doors, and our boat's just 23 feet.)
 
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