Research prior to investigation may have
indicated the architect, builder or a building's date of construction.
In the absence of such information, architectural histories and
field guides to architectural style can help identify a structure's
age through its form and style.
Any preliminary date, however, has to be
corroborated with other physical or documentary facts. Dates given
for stylistic periods are general and tend to be somewhat arbitrary,
with numerous local variations. Overall form and style can also
be misleading due to subsequent additions and alterations. When
the basic form seems in conflict with the details, it may indicate
a transition between styles or that a style was simply upgraded
through new work.
The architectural investigation usually
determines original construction details, the chronology of later
alterations, and the physical condition of a structure. Most structures
over fifty years old have been altered, even if only by natural
forces. People living in a house or using a building for any length
of time leave some physical record of their time there, however
A longer period of occupancy generally
counts for greater physical change. Buildings acquire a "historic
character" as changes are made over time.
Changes to architectural form over time
are generally attributable to material durability, improvement
in convenience systems, and aesthetics.
- First, the durability of building materials
is affected by weathering, temperature and humidity, by disasters
such as storms, floods or fire, or by air pollution from automobiles
- Second, changes in architectural form
have always been made for convenience' sake fueled by
technological innovations-as people embrace better lighting,
plumbing, heating, sanitation, and communication. People alter
living spaces to meet changing family needs.
- Finally, people make changes to architectural
form, features, and detailing to conform to current taste and