*5.2.3.4 Connectivity and permeability*

The concepts of permeability and connectivity are derived from the relationship between the block and the street. The correct definition of this relationship can add to the durability of these two urban elements (blocks and streets) over time. These concepts primarily refer to how the environment is blocked.

In fact, the distinction between permeability and connectivity becomes clearer in practice. Connectivity refers only to the number of connections between blocks (the number of intersections) and is a quantitative concept, while permeability is defined as the way streets interconnect and depends on criteria such as the width of

proximity and similarity, as well as spatial hierarchy in urban spaces. Continuity in the access network is also related to the way pathways are connected to each

Block faces Back and front *Source: Adapted from: Boffet and Serra [21]; Krier [5, 7]; Carmona [2]; Siksna [4]; Talen [10]; Conzen [11]; Jacobs [13]; Maitland [16]; Song and Knapp [14]; Owens and Southworth [17]; Bürklin and Peterek [9]; Rossi [22];*

The spatial hierarchy deals with community and privacy. In the transition from public space to private space, at the level of block, frontage of buildings, and in the

space between blocks, the block edge plays an important role [10, 26].

**Concept Items Criteria Indicators** Variety Mixing of land uses

*Sustainability in Urban Planning and Design*

block

Green infrastructure

Connectivity Street pattern and accessibility

Permeability Patterns of streets

*Moudon [20]; Berghauser Pont and Haupt [19]; Oikonomou [23].*

*Practical checklist to analyze and design urban blocks.*

Mixing of ownership

and activities in the

The variety of spaces

The variety of buildings in the block

Income and social status mixing

The type of street connection to the entire network

and accessibility

The type of street connection to the entire network

Connections of sidewalks

Checking the activity buffer of kindergartens, schools, libraries, government services, etc.

The amount of squares, recreational and leisure

spaces, play grounds, parks, etc.

architectural details

residential complexes

Public and private

The block's area

The blocks' faces

The length of cul-de-sacs The number of blocks The number of access points

The angle of intersection

collector, and distributor)

Intersection distance Intersection density

The number of intersection The number of blocks The number of access points

Different types of buildings, diversity in

Combination of independent villas, semiindependent dwellings, apartment buildings, and

the streets, green roofs of buildings

Green corridors among blocks, vegetation along

The number of connections at an intersection

The type of street hierarchy (arterial, local,

other [2].

**196**

**Table 2.**

*5.2.2.1 Spatial hierarchy*

are in the direction of reaching durability. The third quality, i.e., diversity, is a quality of space that changes urban blocks and superblocks into more flexible spaces via the presence of various social groups, mixed uses, and diverse spaces that in turn

*Toward Practical Criteria for Analyzing and Designing Urban Blocks*

The concepts of permeability and connectivity represent the relationship between the block and the street. These concepts are primarily related to the arrangement of blocks in the environment, so they can be affected by the size of the block, which, in turn, affects the block's durability [4]. Therefore, it can be concluded that the rate of permeability and connectivity affects the longevity and

Designing contemporary urban spaces requires form patterns that can be adapted to different aspects and at the same time address social interactions and encounters. This study was carried based on the concern about the status of blocks in the context of urban design and looked for a way to place the block as a focal point in urban design studies. Different concepts derived from different theories and approaches were clustered, and the interconnections among them were reviewed and defined and ultimately formulated in the form of an evaluation checklist. The checklist includes various form relationships that have a bearing on the social aspects of urban space. It has the potential to be used in the future as a framework for analyzing existing urban blocks and finding their problems in future studies, as well as for structuring new designs, taking into account context charac-

Department of Urban Planning and Design, School of Architecture and Urban

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

help them survive over time.

*DOI: http://dx.doi.org/10.5772/intechopen.90504*

durability of urban blocks.

**7. Conclusions**

teristics.

**Author details**

**199**

Amir Shakibamanesh\* and Bita Ebrahimi

provided the original work is properly cited.

\*Address all correspondence to: shakibamanesh@ut.ac.ir

Studies, Art University, Tehran, Iran

#### **Figure 8.**

*Distinction between connectivity and permeability: from light gray to dark, streets become less but connectivity remains identical. (source: [29]).*

the paths, the access hierarchy, as well as the visual and physical factors that induce a sense of movement (**Figure 8**).

### **6. Discussion**

The checklist is the result of this study, as the first step in this area can be a basis for urban designers to look at urban blocks from a novel viewpoint and provide a suitable basis for the effectiveness of this element in urban design studies. Although this study is the initiator of this endeavor, in future studies it will be possible to develop and complete other factors related to the blocks.

The results show the breadth of the concept of block, hence the complexity of understanding and application of this element in the design of urban spaces, and can develop a comprehensive look at design. Finally, the mediating role of this element can balance other elements of the city.

Spatial balance, continuity and integration, and longevity and durability are macro-concepts of the list that are conceptually and functionally related to other factors and are divided into three categories of concepts, criteria, and indicators. Spatial balance is the relationship between mass and space; therefore, it can include as its subcategories "configuration and arrangement" and density, which are defined in terms of the arrangements of masses in space and the manner in which the space is occupied by masses, respectively. Subsequently, each of these factors subdivides to other factors at a smaller level. If continuity and integration are defined as the existence of the rhythm and order in the form of blocks (at the levels of superblocks, neighborhoods), and the connection in the access network, then it can include the spatial hierarchy (semiprivate, semipublic, and public) and the privacy and homogeneity among the blocks that can be used to create and interconnect such factors.

We have defined durability as capability to last over time, which can be achieved via qualities such as memorability, adaptability (of land uses and climate), diversity, permeability, and connectivity, because memorability transforms the block into collective memory and adaptability helps accepting new or varied land uses for the blocks in their lifetime or adapting to changes made over time, and thus, both

*Toward Practical Criteria for Analyzing and Designing Urban Blocks DOI: http://dx.doi.org/10.5772/intechopen.90504*

are in the direction of reaching durability. The third quality, i.e., diversity, is a quality of space that changes urban blocks and superblocks into more flexible spaces via the presence of various social groups, mixed uses, and diverse spaces that in turn help them survive over time.

The concepts of permeability and connectivity represent the relationship between the block and the street. These concepts are primarily related to the arrangement of blocks in the environment, so they can be affected by the size of the block, which, in turn, affects the block's durability [4]. Therefore, it can be concluded that the rate of permeability and connectivity affects the longevity and durability of urban blocks.
