[Strawbale] Brian Z. - welded wire mesh

[activism98201 at verizon.net]

Shody (and others),

I'm thinking along the lines of passive solar design, whereby thermal mass is used as an energy sink.

Yes, one needs to insulate under the slab.

Regarding the temperature of the earth, it's not consistent, and its especially not so if you're going by the near-surface level.  Only after going down a couple of feet (or so, below the frost level?) are you going to establish a fairly stable (average) temperature (one that you'd find would provide an energy benefit to a living space).


-Mark Nagel
Everett, WA


=====================
From: Shody Ryon <qi4u at yahoo.com>
Date: 2007/10/14 Sun AM 12:44:03 CDT
To: strawbale at listserv.repp.org
Subject: Re: [Strawbale] Brian Z. - welded wire mesh

I was going to use R 15 under the slab. I do not think
many people use more than R 15 (and 15 mill commercial
quality plastic $750 and the insulation itself will be
a little pricey too), and I think the reason is that
the earth has a thermal storage capacity of 1/2 that
of water and some insulation capacity too, although I
am speculating.
If the earth naturally has a temperature of the yearly
average of the area, then I would be warming it when
the air temp drops below about 35 or 40 degrees F.- I
think.
With 2x10 joists filled with cellulose; 9"x R3.8=
R34.2 and minus the energy of warming the earth. I
think the earth would be an energy drain accept in the
hot part of summer.
Cheers,
Shody

--- activism98201 at verizon.net wrote:

> What about the energy savings from thermal mass (of
> concrete)?  This, or foucrse, assumes that such a
> floor is properly designed to sync heat.
> 
> 
> -Mark Nagel
> Everett, WA