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Re: How much glass for solar gain?



Ross M Donald  <AE%SJSUVM1.BITNET@cmsa.Berkeley.EDU> wrote:

>     Guidelines for South facing glass:
>
>     Radical:  as much as possible

I agree. Well, enough to heat the house 100%, anyway, as a low-thermal-mass
sunspace, with a smaller glazed area inside in front of a high-thermal-mass
solar closet/sauna for cloudy days. And not just glass. Alternative sunspace
glazing include polycarbonate plastic (Dynaglas or Replex) or even good old
5 cent per square foot, 3-year greenhouse poly film...

>     Now, forget the guidelines.

Good idea...

>     Consider 5-20 gallons water in direct gain per
>square foot of glazing.  Too hot, too much temp flux -
>add more mass;  too cold - reduce mass, add movable
>insulation.  Get Mazria:  The Passive Solar Energy Book.

This works pretty well in the southwest, but I'm fairly convinced that
in places with a few cloudy days in a row, direct gain is bad, unless
there is movable insulation. Or at least it is much better to use passive
or low-power active air heaters on the south walls, with a good insulated
wall behind them, and a higher-than-living-space temperature heat battery,
inside the house, that can be well-insulated, vs a masonry floor behind
a big uninsulated picture window in the living room.

Nick