"nightjar .uk.com" nightjar@insert my surname here wrote in message
...

"Jason" wrote in message
.uk...
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That's what I would ideally like. I guess the temperature rise will
depend on the thermal mass inside the room - lots of heavy brick and
stone would help, and that would need to be on the inside of any
insulation.

Marble slab shelving used to be a feature of all the pantries I remember.

Some of the council houses around here, built in the fifties, have solid
concrete slabs about three inches thick. I suspect they were cast in-situ,
and serve the same job as the marble.

-- JJ