Overview
In our system, a block is defined as a unique area enclosed by a closed loop of linked network edges. Loops are generated in our system as a result of the Overlap Parameter (Ov), shown previously (p.104-105). A larger Ov (from a possible range of 0 to 1) results in more redundancy in distribution paths and a more highly connected network overall.
In our pursuit of a highly connected, highly social urban fabric, like that found in our reference cities, like New York, we showed that higher Overlaps were preferable (p.108). It was also shown however, these higher values result in escalating infrastructural investment costs (p106-107). Additionally, these loops occasionally include terminal points of distribution trees, which, in effect, become ‘dead ends’ or ‘cul-de-sacs.’ A higher Ov would result in fewer of these dead ends however would also result in smaller blocks, which, as we can see now, would diminish the size of continuous productive plots. Therefore we recognise, in the implementation of our system, several tissues will need to be generated using different values, and the various benefits will need to be weighed in choosing the fittest output.
Our sample tissue, generated with Ov = 0.7, shows a diverse distribution of sizes of productive commons, accommodating different scales of production and a good balance of network cost and connectivity relative to our reference cities.
Analysis
Closed loops, or Blocks, were identified in the sample tissue sorted be number of edges. Various properties were measured, including areas of production, dwelling and open space.
Comparing the properties of the blocks revealed:
Number of edges corresponds to the relative area of the block. Blocks with fewer sides are smaller and visa versa.
Of the 24 blocks, half have 4 edges. However, 46% of the total surface area of all the blocks, is delivered by the blocks with 6 or more edge components, which are only 5 blocks.
Also, when the size of the blocks increases, the area of production grows, from 25% for the smaller blocks to a maximum of 53.5% for the larger ones. This suggests that the larger blocks are more suitable to be used for commercial farms.
Lastly, we can see that the average built space (coverage) for all the blocks is 61% of the area. The different blocks show a range from 41.9% to 73.4%, providing different densities of built morphology throughout the tissue. This will inform further differentiation in the urban experiences in the neighbourhoods.
The large edges may require intersections with a secondary path network to provide more choice for social movement.
Performance of the Productive Block
To understand these figures, relative to our reference cities, we can compare these findings again to the Manhattan block.
As mentioned before, the area of the Manhattan block is 43% of the size of our sample Productive Block shown here. Therefore numbers should be considered as percentages, not compared directly.
The built area in Manhattan is with 60%, slightly larger then the coverage of 58% in our block showed here.
The key difference however is in use of the open space between the two tissues.
In New York the remaining open space is nearly completely devoted to circulation (with almost double the length of cirulatory perimeter, 1.7x when compared to the same area); whereas in our new Productive Block, a considerable amount of open space has been generated for Edible Infrastructures, in all three spatial zones; on the circulation paths, within the built clusters, and within the Productive Common.
Two Types of Open Space
We’ve seen how the emergent structure of our Productive Block organises open space into an interior Productive Common and an Urban Circulatory Corridor bounding its edges.
Next we’d like to look at how the two open space types are related, how they might connect, and look for opportunities to facilitate flows of people across both, making the productive areas accessible to public. We can see the two systems clearly across the tissue by identifying the urban voids, and sorting the spaces into: those within a given range of network edges, and those outside that range, and in the 'interiors' of the blocks.
A survey of the resulting diagram shows that in a few cases these different types of open spaces connect, but more often the productive commons are isolated into islands, trapped within an enclosure of built form. While this structure serves to facilitate production by concentrating open space into continuous workable plots, it denies much of the inhabitants access to one of the primary resources treasured by most urbanites, access to open green space. Furthermore, it continues the long standing separation of consumers from their food sources. In the next section we'll look at how we might link these islands of open space into a new kind of urban network.
