Cob: strawbale/cob on the inside

[Paul]

Lots of other ideas are in use and have been for a very long time. Nobody's
waiting for some wall that will let heat in but insulate it from going out.
The point of inside thermal mass is to heat it by south-facing glass during
the midday hours. Then the thermal mass  radiates gradually into the house
during the night. This concept in one design or another is the basis of
most if not all  passive solar books and houses of recent decades. Trombe
or modified Trombe walls, envelope houses, thermal mass basements or crawl
spaces, and especially sunrooms use the greenhouse effect to recharge
during the day and release the heat into the living area at night.
Obviously it helps to curtain or shutter large areas of glass at night to
cut reverse heat loss. All these designs work with varying success,
depending on other factors. Tight insulation in walls and ceilings is
always needed, but on the outside, not the inside. Walls can be anything,
cob included, so long as there is direct gain on thermal mass floors or
subfloor from south glass. But perimeter insulation also keeps the subfloor
or crawlspace warm and dry.

--paul, webmaster http://globalcircle.net/00building.htm
peace and liberty, sustainability and justice

*********** REPLY SEPARATOR  ***********

On 2/13/02 at 9:27 AM Matthew HALL(SED) wrote:

>ric at mx5.net writes:
>>But if the thermal mass is insulated from the outside sun, how does it
>pick
>>up the energy to re-radiate......
>>
>Correct observation - whenever you use thermal insulation with thermal
>mass there is a conflict. If
>you insulate the inside of the house, the mass wall heats and cools very
>nicely but this effect is
>largely separated from the house interior by the insulation layer which
>seeks to nullify and heat
>transfer processes. If you insulate the outside then any heat which is
>stored by the walls is kept
>within the confines of the house. The only drawback is that the walls
>cannot be heated as
>effectively by solar radiation. 
>
>Just to clarify, the rather short sighted view taken by most building
>authorities is one that
>suggests a building is only up to scratch thermally if it has high levels
>of insulation (low U
>value [UK]), thermal mass concept is ignored. It makes no difference to
>them whether or not you
>have a thermal mass wall as long as you satisfy their arbitrary U-value
>requirements to make the
>grade. Earth walling has a relatively low level of insulation, and so to
>reach the required
>insulation value one would have to build an earth wall of immense
>thickness. This is fine if you
>have plenty of soil, labour and time etc. Perhaps another way to acheive
>the same insulation value
>would be to use an external outer insulation layer that allowed solar
>radiation to pass thorugh but
>prevented the leakage of infra red radiation. One example of this would be
>triple glazing low 'e'
>argon filled units, very expensive. Any other ideas?
>Matthew
>
>>>____________________________________________________________________
>>>Matthew Hall - PhD Research Student
>>>Centre for the Built Environment
>>>Unit 9 Science Park
>>>Sheffield Hallam University
>>>Pond Street
>>>Sheffield S1 1WB
>>>England
>>>
>>>Tel: +44 (0) 114 225 3200
>>>Fax: +44 (0) 114 225 3206
>>>E-mail: M.Hall at shu.ac.uk
>>>
>>>
>>>
>>>
>>>
>>>
>>
>>
>
>
>____________________________________________________________________
>Matthew Hall - PhD Research Student
>Centre for the Built Environment
>Unit 9 Science Park
>Sheffield Hallam University
>Pond Street
>Sheffield S1 1WB
>England
>
>Tel: +44 (0) 114 225 3200
>Fax: +44 (0) 114 225 3206
>E-mail: M.Hall at shu.ac.uk