[Strawbale] water in attic cross post 2

[Shody Ryon]

Re: Thermosyphon sunspace using pebbles in ceiling

From: "Jim Foreman" <jimfore at ...>

> That would take one honkin strong structure to hold
it up.
> After all, 30 lbs sq/ft is normal for the roofs with
snow load.

30PSF is the snow load across Chicago, Detroit, Ohio,
etc.
30PSF is also the standard design live load for
bedrooms,
and other secondary floor areas. Pirmary spaces, like
living, family and dining rooms, need to support a
live load
of 40PSF. Then there is the dead load, too. A cubic
foot
of gravel or rocks weighs about 100 pounds. Since
there
is also not much energy density, the load would need
to be
spread over a large area, including the ceilings of
the larger
rooms. That much load, over those long spans, requires
a
very hefty structure. My water storages, not only
weigh
only abour 40% as much for the same energy capacity,
they also only take up about half as much volume,
there-
-fore the smaller, lighter volume can be stacked over
to
the side, much in the areas of attic that would be
hidden
behind the knee walls anyway. This also puts the much
lighter load, handily over the wall between the
sunspace
and living-space, where there is little or no need for
any
larger structure, except perhaps a shear wall or two,
and maybe larger headers in that one wall. It is
fairly
minimal, and seldom exceed the normal loading of the
floor areas. On the other hand. putting many tons of
rocks, up above the living space is in a totally
different
structural league, and nothing at all is gained from
it.

-Laren Corie-


      ____________________________________________________________________________________
Be a better friend, newshound, and 
know-it-all with Yahoo! Mobile.  Try it now.  http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ