Saturday, February 27, 2016

Air vent under bunk routing Feb 27 2016

 Today's progress was putting in supports to hold up the bunk. A while back, I was having an e-mail conversation with Dave Z, about a clever idea I saw in one of the Junk Rig Association magazines, where someone in a northern boat was finding his feet cold while visiting mid winter. His solution was to make a tube of cloth with a small fan at one end, blowing  heat from up by the roof down to the floor. Dave said he was thinking about an air passage from under the dinette, around the bunk, and up beside the wood stove. Here is my interpretation of that, in progress.

Here are the air holes, from either side, penetrating the port side saloon to bunk bulkhead. I am doing a balancing act in their location, wanting a location out of the way of storage, without weakening the bulkhead too much. There is about 10 square inches of  air hole, as well as a limber hole.
A second layer of plywood will be screwed to the outside, so it is removable for annual painting and  cleaning. This will give a 3 inch wide channel, about 8 inches high across the foot of the bunk. It's amazing how much time is consumed trying to figure out these little details. Hopefully everything will work and I will get toasty warm toes when running the wood stove


  1. Hi Dennis,

    I like the general idea of circulating air and the interesting example that you provided (clever idea --> "Some Like It Hot" article). That said, I like your/Dave's ideas better of integrating air flow channels and ducts into the boat while you're building it.

    Can you please explain more about your idea? First, an overview of what you're trying to do, in which room, and how you see it all working together. That would be a big help.

    As an aside, though two northern boys like yourselves wouldn't care much about this, I'm also trying to figure out how to do the reverse during the summer -- take hot cabin air, cool it, and put it where it needs to go. Ideally, the same channels and ducts would work for heating and cooling ... and do so without creating an organic mold farm!

    Hmmm ... but what about mushrooms?


    (And while I'm at it ... when are we going to see the next boat project update? ;-)

  2. The intent is to have the intake up near the ceiling of the pilothouse,(the hottest air source when the stove is lit) and have it run down along the stove pipe, around the exterior of the cabin through the passages shown, then exit at foot level in the dinette area.. I intend to have a 12v computer fan driving the flow. Dave was suggesting that the updraft of the pipe along the stove might pull enough to cause the cold floor air to be cycled up to the ceiling, until the warm cabin air was brought down to floor level. The path is the same, just opposite direction, and no power required. I need to build it and try it out to see which way works best, or might be that I run the fan to start, then shut it off and allow convection to reverse the flow to help keep things stable.I have no idea how well it would work for cooling though, or condensation problems. A wood fire is usually really good for drying things out, so I am not too worried about that problem.