In this situation, it is essential to develop time-saving methods of
comprehensive building surveying. Remote sensing is one tool, often a
very useful one. In many cases additional sources of information must
be used. and aerial photographs are often very convenient in such
combined studies.
I will relate a few studies where aerial photographs were used to
describe certain features of a built environment.
The Swedish Civil Defence Administration commissioned our Department
to study population, use of land and buildings; types of residences:
and building density in four Swedish communities. The result was to be
presented on maps which were to be used as examples in civil defence
planning. It ought to be noted that this was not from the beginning a
research project but more or less an ordinary planners' commission
where we had to study unconventional methods as a part of the work.
Some of the required information was fairly easy to get hold of. The
population; for instance; could be mapped with satisfactory accuracy
with the census-registration and employment statistics as a basis.
Land use could be studied on master plans and town plans. Building
density and types of residential houses; however, were difficult to
determine. In Uppsala, the first community to be studied, we tried to
derive data by interviewing communal officials and by studying floor
space indexes. The quality of information thus accessible varied very
much and the result was not satisfying. A fairly extensive amount of
field surveying was needed. In spite of this, we were not able to map
the building density, but had to present rather scanty floor index
tables.
At this point, I have to comment a little upon the role chance plays in
our choice of work methods. In Sweden, most architects never work with
remote sensing and photogrammetry. These subjects are not included in
our training. We knew, of course, that aerial photographs existed and
were used for cartographic purposes: but we had no idea of the use we
could make of them. But I have a daughter, at that time about ten years
old, and she had a very good school-friend. I met the father of this girl
at a parents’ meeting at the school. and we started to talk about our