[Cob] RE: Solar radiant floor

[Peter Ellis]

   >From: "Amanda Peck" <ap615 at hotmail.com>
   >To: coblist at deatech.com
   >Subject: RE: [Cob] RE: Solar radiant floor
   >Date: Mon, 24 Jan 2005 08:58:41 -0600
   >
   >
   >Never tried this, so I'm guessing.
   >
   >any or all of several possibilities.
   >
   >a) Sand has some nice properties.  If it's small and pretty uniform
   >it will protect the radiant tubing from cuts and deformation. Can be
   >leveled for the floor above it.  May have some desirable heat
   >transfer/storage properties as well.  Drains, doesn't wick.
   >
   >b) Soil, by contrast, may wick water up from the ground.  If it's
   >clay, or good organic dirt, you've probably got better uses for it
   >than letting it sit under the house.  If it's silt, not much
   >structure--goes from hard beyond belief to something with the
   >texture of slip without any problems.
   >
   >c) Not at all sure if you want your floor at ground level, and the
   >plumbing BELOW it.  I do like houses on not more than a slight rise
   >from the ground, but I live in an area that gets saturated soil
   >easily, parts only dried from pre-Christmas rains and floods this
   >weekend.  There may still be some water perking through the soil
   >down at the barn--or will be as soon as it thaws.  There's been a
   >thread here about moldy linseed oil floors.  Humidity from above or
   >water from below?  I don't know, but I wouldn't want to chance it.
   >.................

   I've done a bit of reading on the subjects of AGS and PAHS - Don's a
   regular contributor on the organic architecture list.  The basic
   principles in both of these approaches are very similar, and one of
   the fundamentals is you need to provide a water barrier above the
   earth you're going to be using for heat storage.  If it isn't
   protected from water flowing through it, it won't work to store heat,
   the water will carry the heat away.

   So it should not be a matter of drainage of the earth you're using as
   your heat storage.

   And the "plumbing" I was referring to would be the tubing run through
   the earth that is your heat storage area - they're just air conduits,
   for heat exchange.  Conventional plumbing should be run conventionally
   (grin).

   Peter