In a message dated 99-03-24 07:03:23 EST, you write:

> In the case of stone vs. fiberglas, it would be hard to believe that stone
>  isn't available.  If the budget predicates substitution, maybe education is
>  the answer.
>
>  Two very real issues come to mind:
>
>  One being the loss of the true artifact by substitution of some of it's
> parts.
>  The artifact itself is a complete entity, made up of many parts. If we
> choose
>  to substitute the approved (budgeted) replacement whenever a part goes bad,
> we
>  eventually lose the artifact completely.
>
>  The second being the loss of historic record by replacement of fabric. If
> the
>  artifact eventually becomes the property of someone who believes in it's
> true
>  preservation, the decisions as to how to replace the worn out parts gets
>  extremely moot when no one knows what existed prior to the fiberglas.
>
>  Please excuse the philosophical wax.

This debate seems to be on a tangent to the original discussion... it isn't
about the appropriateness of substutite building materials. The debate centers
on the appropriate treatment for materials that do not function as they were
designed to function. Is it appropriate to substitute materials when the
original *does not function properly*? If an experimental roofing material
does not keep water out of the building, then how exactly does it's
preservation benefit the building as a WHOLE? When does the preservation of
one element override the preservation of the artifact as a whole?

Preservation of bad design is a never-ending nightmare of throwing money into
a black hole. Here in the "bake sale" sector of preservation, we usually don't
have enough money to flush down the toilet preserving experimental failed
technologies (Mary-- the flat roofs of Kahn's picnic pavilions at the Bath
House come to mind...) (If anyone does have enough money to flush in such a
manner, my resume is available upon request...)

If by substutiting a more efficient material (with appropriate documentation
of the original) one can ensure that the artifact *as a whole* is better
preserved, it seems appropriate to consider this treatment as a long-term
preservation solution. Taken in the long view, such a change would eventually
acquire historic significance in its own right.

-Heidi