[Greenbuilding] [BULK] Re: Trying to maximize passive solar gain...

[Lawrence Lile]

>...Kachadorian's SOLAR SLAB...is a design that isn't hugely limiting
>to the architecture but may provide 40-50% of a northern home's
>heating needs.


>Basic plan is a concrete slab floor poured over a concrete building
>block "radiator". Manifolds are formed in-place.  Relies primarily on
>passive convective airflow (room air)...

Yow!  This is the most common mistake in solar houses of the '70's.
There is no way to clean a space like that, and it won't drain unless
carefully designed.  Works great for a year or two, until either
spiders, mold, mice, moisture or all four start camping out in the
manifolds.  Many of these designs were abandoned because of indoor air
issues.  

Additionally, don't create spaces that can trap fire.  This was a
mistake a friend of mine made when building a solar house.  When it
caught fire, there were spaces between inside and outside walls,
inaccessible manifolds designed to circulate air, that the fire
department could not get to quickly, that helped to spread the
conflagration that eventually consumed the house, while the firemen
helplessly watched it burn.  

Were I to try to put manifolds under concrete, I'd use some kind of
smooth pipe arranged with cleanouts, and arranged to drain moisture.
Never use concrete blocks or inaccessible concrete surfaces. 

--Lawrence