Researchers in the academic literature circle two keywords: urban fabric development and sustainability. Mainly, here we are concerned about professional practice. Urban fabric development and sustainability have three common pillars: Land use, urban densities, and transport system. Surely, changing one of these pillars will have a concurrent influence on the other two pillars. So, in the following paragraphs, we will stand on the common criteria between these pillars when change applies to the urban fabric. Urban designers must achieve a good urban form at the same time they achieve sustainability. So, what is a good urban form? And what is sustainability?
What is a good urban form ?
Researchers, practitioners, and academics have almost a consensus on the characters of a good urban form. These include discouraging zoning and achieving mix-use. Also, they advise slowing down decentralization process. Extreme compact cities are not desirable. In addition, decentralized towns around a city are preferable. Increase and promotion for inner green urban space. Finally, state to develop public transport in all measures.
Planners and urban designers must direct People’s intensive activities around public transport nodes. That’s so to make public transport less costly and in reach to all people.
What is sustainability?
Sustainability is the efficient use of resources without damaging the balance of the ecosystem. Many countries in the world have developed their own green building and development systems. For instance, America and Europe have developed green systems for building and development (LEED, GREEN GLOBES, BREEAM, DNGB, GREEN STAR, MILJOBYGGNAD) you can check individually. Asian countries also developed their own systems (BEAM PLUS, CASBEE, BCA GREEN MARK SCHEME) take a look for further details. Surely, these systems core elements are to reduce utility consumption, reduce waste, using derelict land and developed land, decrease of environment damage by promoting clean energy and public transport, and achieving indoor and outdoor human use and wellbeing.
Urban fabric development common criteria
In work best practices pushed all urban fabric development towards achieving green building and development credits and rating system. So, we are going to go through land use effect on development. To develop land a planner or urban designer conducts various tests. These include, market forecast, land suitability, carrying capacity, and committed land analysis. Carrying capacity analysis is one of these major and important tests. Also, from the planning point of view, planners define the carrying capacity as the ability of a natural or man-made system to absorb population growth, physical development, or intensity of use without significant decline or failure (Schneider, 1978).
Analyzing land use with these methods is very complex. For simplicity, to make land for residential use planners must consider various factors suitable topography, near to water surfaces. In addition, near to recreation areas and parks, next to shopping areas, easy access and near work areas. Industrial land use should consider several factors available: raw material, transportation, market location. Also, other industry’s location, utility supply, and regulatory laws. Land use for public building considers factors like avoiding locations increasing congestion, areas not disturbing business centers, and to be in transition areas between land uses. As we can see here that the common factor between these land uses for consideration is transport.
Scholars in transport planning link land use to employment. Land required for certain use is calculated as the number of acres needed for a certain industry. For example, doing so by dividing the projected employment in that industry by an average number of employees per acre. So, specifying land use leads to demand in travel. Defining land use leads to transportation effects. These are explored by simple trip generation, trip distribution, and modal split analysis (transport modeling). Opposite direction defining transportation alternatives are analyzed using simplified land developments modelling. An approach used in transport planning called “future urban spatial structure design approach”.
Urban densities come as the second pillar urban designers consider in urban fabric development (read here my paper review on high density development). Developed nations built many homes in suburbs due to the need for quiet living. This leads to more car use, more parking, heat islands, pollution, gas emissions, traffic jams, poor land use, and less public transport in low-density areas. Growth in population and jobs in city centers caused a shift to urban living. To reduce car use, sustainability groups push for higher development densities. High-density make mass transit feasible, boost business, and aid energy systems.
Urban designers consider transport systems as a major component to design and plan in the urban fabric development. Developing transport systems requires good control on governance, finance, infrastructure, and neighborhoods. Public transport development reserves land for development but increase land price within the accessed areas. Control on land that means ownership is a major factor in developing public transport. Building public transport nodes requires more than land ownership, but land uses that support the high cost of building them, which is high-density development. Here, high-density development is a critical factor in planning and designing transport systems and relevant transport nodes.
As we have discussed here that defining land use creates demand for travel. Thus, direct impact on developing transport system or constructing new transit system. Relevant entities run various models and calculations from two directions, land use and transport systems. If the new development or the existing urban fabric development requires transport system development, then two alternatives’ planners introduce. If they consider developing the area towards low density, then they will not consider mass transit. that’s because it will not cover the cost of implementing the development. Accordingly, they plan car use and a new road network for construction.
So, defining land use automatically requires change in transport system, adjusting transport system is determined by the urban density of the specified land use. Here we defined the concurrent influence of land use, urban densities, and transport system on the urban fabric development.
Related topics
You can explore deeper the effect of planning and urban design on the formation of the urban fabric by reading my article series CITY IN LAYERS 1,2,3,4,5,6,7