Techniques > Systems
> Windows > Conservation
Whenever possible, repair a historic window, rather than replace
it. In most cases it is in fact easier, and more economical,
to repair an existing window rather than to replace it, because
the original materials contribute to the historic character
of the building. Even when replaced with an exact duplicate
window, a portion of the historic building fabric is lost and
therefore such treatment should be avoided. When considering
whether to repair or replace a historic window, consider the
First, determine the window’s architectural significance.
Is it a key character-defining element of the building?
Typically, windows on the front of the building and on sides
designed to be visible from the street, are key character-defining
elements. A window in an obscure location, or on the rear
of a structure may not be. Greater flexibility in the treatment
or replacement of such secondary windows may be considered.
Second, inspect the window to determine its condition.
Distinguish superficial signs of deterioration from actual
failure of window components. Peeling paint and dried wood,
for example, are serious problems, but often do not indicate
that a window is beyond repair. What constitutes a deteriorated
window? A rotted sill may dictate its replacement, but it
does not indicate the need for an entire new window. Determining
window condition must occur on a case-by-case basis, however
as a general rule, a window merits preservation, with perhaps
selective replacement of components, when more than 50 percent
of the window components can be repaired.
Third, determine the appropriate treatment for the window.
Surfaces may require cleaning and patching. Some components
may be deteriorated beyond repair. Patching and splicing
in new material for only those portions that are decayed
should be considered in such a case, rather than replacing
the entire window. If the entire window must be replaced,
the new one should match the original in appearance.
3.0 Windows, Design
Guidelines for Residential Historic Districts in Salt Lake
City, Salt Lake City Historic Landmark Commission, Salt
Lake City Corporation, 1999.