Environmental Engineering Reference
In-Depth Information
4.4.1 Defined Neighbourhood (with Quality Architecture
and Urban Design)
Informal areas usually have defined edges that separate them from their
surrounding areas—such as a railroad, canal, or ring road. They have a dis-
tinct urban pattern, especially those following agricultural basin subdivi-
sions. However, they do not have centres; instead, the main streets act as the
centres with a concentration of uses and markets. Secondary streets act as
recreational spaces where children play due to the prevailing sense of secu-
rity (see Figure 4.1) [8].
What these areas lack is an overall urban vision because they are built incre-
mentally. Moreover, where the land is privately owned, open spaces are usually
overlooked because they have little or no economic value. Also, when there is
an open space, it is not taken care of unless there is a strong sense of commu-
nity among residents. As for the quality of architecture, in some areas, it can be
poor but can be upgraded to promote local character and sense of place.
However, the prevailing visual image is homogeneous due to building
with the same materials, bricks and concrete, and following the same urban
pattern (see Figure 4.2).
4.4.2 Compactness
Informal areas are compact in density (e.g.: 890 person/ha in Boulaq
Al-Dakrour district), exceeding other formal areas due to the private devel-
opment mechanism, thereby providing a perfect setting for walkability and
energy efficiency. The buildings are stacked together with usually only one
free facade that minimises thermal loads, maximises space use and enhances
energy efficiency. Compactness can be explained through the following
aspects.
4.4.2.1 Walkability
Informal areas are characterised by narrow streets that are mainly pedes-
trian. Services, which are mainly community built, are usually within less
than a 10-minute walk (see Figure 4.3). However, government provided ser-
vices may not exist in close proximity.
4.4.2.2 Connectivity
Streets are interconnected; however, they are more favourable for pedes-
trians than vehicles because they are narrow. Although there is a network
of wider streets, due to increased traffic load, they are usually congested—
especially at marketplaces and area entrance points. Moreover, streets
can be too long and without crossings, which decreases connectivity (see
Figure 4.4) [9].
