Enclosing historic house in glass-walled structure

Barbara Appelbaum <aandh [at] pop__mindspring__com> writes

>Sarah Price <sprice [at] rogersark__org> writes
>
>>Our museum is planning a major expansion and one of the design ideas
>>that is under discussion (sometimes argument) is enclosing our
>>historic brick home within a larger glass-walled structure. ...
>
>There are many potential consequences of doing what your museum is
>proposing, including green-house heating of the inside of the glass
>structure, condensation on the inside of the glass in cold weather,
>difficulty in controlling glare, potential damage to the brickwork,
>etc.  I would imagine that the energy costs for air conditioning a
>glass structure would be monumental, and that surrounding the
>original structure with a glass one would  make environmental
>control of the original building extremely complex. ...

Barbara Appelbaum comments that solar gain, condensation, and the
high cost of air-conditioning are all potential problems in
enclosing a brick structure inside a glass one, and she is correct.
But as the conservator in charge of collections inside 36 historic
houses throughout New England, I can say that there are great
potential advantages to enclosing an historic structure inside a
larger one as well.

Maintaining a stable environment inside an historic structure
throughout all four seasons of the year is a difficult, if not
impossible task. Proper stewardship and safeguarding of collections
require a stable environment, and yet when conditions outside a
building differ dramatically from those maintained inside the
building, the building fabric itself can suffer enormously. A second
structure surrounding the historic one would serve as a buffer,
allowing the building and its contents to be subjected to the same
environment inside and out, thereby protecting both the building and
its contents.

Problems of air-conditioning, condensation, and solar gain, as
mentioned by Barbara Appelbaum, are problems in glass structures
which need to be resolved whether or not they surround historic
houses. As for glare, the house currently experiences unmediated
exposure to the sun, since it is outside. I do not believe that
glass would exacerbate that particular problem.

There are a number of museums with experience in maintaining a
stable environment in lass-walled galleries, including the
Metropolitan Museum of Art's galleries devoted to the Temple of
Dendur and its Pacific Island collections. I would investigate the
problems encountered in these galleries and the design solutions the
relevant institutions came up with.

John D. Childs
Conservator
Historic New England
Collections and Conservation Center
151 Essex St.
Haverhill, MA 01832
978-521-4788 ext 711
Fax: 978-521-5172


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                  Conservation DistList Instance 21:44
                Distributed: Saturday, February 23, 2008
                       Message Id: cdl-21-44-001
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