Cob verify?

[Mike]

Perhaps the comparison of a cave was not a good one, but the concept is the
same. To really discuss this, we have to talk about the composition of cob.
For it is not merely mud. The clay and straw have certain insulative qualities
that surpass alot of modern-day building materials. However, to really get a
good idea of the insulative quality of cob, we as interested participants
might want to think about building a small structure in our backyards. Anyone
up to the task?


Speireag Alden wrote:
> 
> Sgrìobh Mike:
> 
> > I have heard quite the contrary. The cob has great thermal mass which
> > means it
> > has the ability to keep temperatures constant both day and night. you don't
> > need a/c, and only minimal heat in the winter. Have you ever heard of a cave
> > having the same average mean temperature all year round? well, cob acts
> > in the
> > same way. A cave is asigned a thermal mass, depending on how deep it is and
> > what the walls and beyond are made of. With cob, the thermal mass is
> > terrific...period. However, the thicker, the better. As long as you have a
> > roof with a high "R" value (to minimize thermal transference), and good
> > quality windows and doors, you can keep your cob house warm with minimal
> > energy output, no matter where it is!
> 
> Mike -
> 
>     Though I like the idea of cob, I am very skeptical of this claim.
> Cob's insulative value is not all that much better than stone, and stone
> houses without good insulation perform very poorly in climates where
> wintertime temperatures stay below the comfort level for long periods of
> time (weeks and months).  That certainly includes Vermont, and also New
> Hampshire, where I live.  Awhile back we had a testimonial from a fellow
> who lived in Minnesota in a stone house; he said that he was always cold.
> 
>     For cold climates, you want to couple an outer layer of insulation with
> the inner thermal mass.
> 
>     In a cob building, you don't have anything like the same mass that a
> cave has; the cave, if it's deep, has many orders of magnitude more mass,
> and also earth-coupling across its entire surface area, unlike cob.  You
> might draw a parallel between a cave and an earth-coupled underground
> house, but not a cob house.
> 
>     Best wishes,
> 
> -Speireag.
> 0>>>>>>(---------------------
> Speireag Alden, aka Joshua Macdonald Alden
> Joshua.M.Alden.91 at alum.dartmouth.org
> Usually found somewhere in the wilds of New Hampshire.
> Nach sgrìobhaidh thugam 'sa Gàidhlig?