Cob: second structure spacing

[Darel Henman]

It's a simple triangle problem.

Most likely winter's when you want the solar energy coming in.

The lowest altitute of the sun is at December 21st.   This is the degree
of one of the angles in the triangle, 90 degrees is the other.  The
other is easy to figure, since all must total 180.  The only other
figure you need is the height of the front structure.  This will be one
side of the triangle (not the hypotenuse).  Then just calculate for the
base triangle side.

Take the altitude of the sun for the period you are concerned about. 
Say from 10:00 A.M. till 2:00 P.M on December 21st.  10:00 A.M and 2:00
P.M would be about the same. Use this to get the most light in the
winter.


The key formula is this:
------------------------
Distance from front structure to back structure is=
height_of_building_in_front / tan(sun's_altitude_angle)

Where tan is short for tangent.  Tangent values are on most calculators
as  "tan".

You don't need a stick to do this the altitude values are avalable or
are easily calculated.   I'Ve seen some on the interent which give the
sun's altitude by month day and hour of day. 

Darel

David Knowlton wrote:
> 
> aha! a question for archimedes. that would depend on the angle of the sun at
> your latitude. you can determine this by gauging the shadow from a stick for
> a whole year, or you could consult astronomy on the net and figure out your
> interesting mathematical problem!
> 
> ps. i think strawbale and cob is the best idea i have heard. get all the
> benefits of thick walls and beauty of cob with less effort!
> 
> david in tampa
> 
> >From: "Jill hotmail" <writejill at hotmail.com>
> >Reply-To: "Jill hotmail" <writejill at hotmail.com>
> >To: "cob list" <coblist at deatech.com>
> >Subject: Cob: second structure spacing
> >Date: Thu, 20 Feb 2003 11:54:07 -0800
> >
> >Thanks for the straw bale tips, though I am not sure I understand it yet.
> >Do you use cob columns in place of the timber framing? and Cob around the
> >straw bales - or do you just plaster?
> >
> >Okay, new question. If I build a small structure. Cold wall to the north.
> >Then build another structure to the south, do I leave just enough room
> >between them for sun to shine in from around mid-morning on; to avoid
> >blocking the southern benefits?
> >  In other words, how far do I need to space structures to maintain the
> >southern benefits, assuming I build the structures north and south of each
> >other?
> >
> >jill
> 
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