> Can you help me find information on the construction of an environmentally
controlled room within another structure

John,
Try the Canadian Conservation Institute at www.cci-icc.gc.ca and click on
"conservation information" to search for documents on-line.  "climate
control" brings up a few, especially mention of a 1998 paper "Environmental
Guidelines for Canadian Archives" dealing with collections housed in
historic buildings.

"Display Materials: the Good, the Bad and the Ugly" is a good overview of
material interactions.  "Relative Humidity and Temperature Guidelines:
What's Happening"
by Stefan Michalski, Manager, Preventive Conservation Services deals with
current views of the topic.

Acidity as it effects artefacts is an aspect of this topic often overlooked
by traditional climate control folks.   Acid glues in modern wood products
are a problem but can be overcome by sealing the surfaces appropriately.

However, it is often said that more damage is done to artefacts by the
people that handle them than by any room condition.   Ergonomic
considerations will probably mean more in the end than fancy climate
controls.

We recently hired a CCI expert for a consultation about artefact and archive
storage.   It appears that today there are not a lot of specific do and
don't standards like in the old days, rather, a good look at the nature of
the items actually being dealt with and then applying a large degree of
common sense and a little chemistry.   CCI likes to keep it simple.   They
suggested that the relative importance of the collection to be protected had
more to do with the choices to be made about how far to go with "controls"
than the familiar notion of "industry standards" that came out of the 1970's
and 1980's.

cp in bc