Generative Code for Social Housing on a Greenfield or Open Brownfield

We recommend the following steps, where we have emphasized the unusual aspects of our method, while leaving more obvious construction details up to the local team:

1. Walk the land to diagnose its condition, strengths, weaknesses, exceptional opportunities, areas needing repair, etc. Identify any candidates for a sacred space: e.g., high ground, prominent rocks, large trees, etc. These are going to be protected and later incorporated into urban space.
2. In many cases, the settlement will have an existing boundary that determines street connections. Where this is not so (i.e. in the countryside) the neighborhood’s outline must be fixed, as it will have an impact on the overall street pattern (Pattern 15: NEIGHBORHOOD BOUNDARY of Alexander et al. (1977)).
3. Walk the land to determine the main street and the main cross street from the natural pedestrian flow according to the topography and features. These are going to represent the Roman Cardo and Decumanus, but will be neither necessarily straight, nor orthogonal to each other. Mark them with poles in the ground carrying red flags. Allow room for street plus sidewalks on both sides.
4. Walk the land once more to visualize where the urban spaces ought to lie (decided by the spots that feel the best to stand in; somehow focusing all the region’s positive signals). These are going to be bulges in the main streets near the center, and ought to contain any sacred spaces, if possible. Apply the principle of tangential flow around an urban space (i.e., the street goes alongside an urban space, not through its middle). Urban spaces can be as long as necessary, but not much wider than 20 m (Pattern 61: SMALL PUBLIC SQUARES). Mark the boundaries of the urban spaces with red flags.
5. Decide on the footprint of houses to partially surround and reinforce the urban spaces. Front walls, with no setback, are going to define the urban space boundaries.
6. Now some major layout decisions must be taken. One possible typology is to use building blocks of two houses deep, not necessarily straight, each with dimension roughly 40-60 m wide and 110-150 m long. Building blocks begin at the edge of the urban space and main streets. The direction of each building block is determined by the flow of the land. Their boundaries will define the secondary roads, which are marked with red flags. Secondary streets form T-junctions (Pattern 50: T JUNCTIONS) at the intersections, and do not cross a main street Secondary streets are narrower than the main streets.
7. At the same time, questions of water drainage are settled, because street direction has to accommodate water flow. Decide where runoff water will drain to outside the settlement so as to avoid flooding. Note if any street has to be graded.
8. Shaping the land begins only now, with the government grading the building ground so that it slopes towards the street on each side for drainage. The streets must be graded where necessary to facilitate wastewater flow as decided beforehand.
9. Participating future residents can lay out their house dimensions, using blue flags. Houses have to come up to the sidewalk, and occupy the full frontage. Other than this, there is complete freedom in the house plan. If a courtyard is included, define it by using the house volume to partially surround it (Pattern 115: COURTYARDS WHICH LIVE). Individual variation is essential to guarantee southern exposure; otherwise the courtyard will not be used after it’s built (Pattern 105: SOUTH FACING OUTDOORS). First, define the buildings around the main urban spaces and at the main entrances. 
10. Once a sufficient number of house outlines have been marked, complete the lot boundaries by using yellow flags. Each plot should be not less than 20 m deep and 6 m wide. Plots are separated by an alley at the back and by a footpath on each side. Plots are recorded and deeds awarded. The remarkable thing is that this is the first time the settlement is drawn on paper (up until now, we have been working only with flags in the ground).
11. The government puts in any infrastructure it is going to provide: electrical utility poles in the alleys, either a water system or a regular distribution of public water spigots, sewerage pipes or a few common gender-separated latrines, etc.
12. The first act of actual building is putting down a concrete sidewalk along the position of all marked house fronts. The government does this along all deeded plots, but not in parts of the settlement that have not yet been planned. It is convenient to complete one housing block at a time. The sidewalk itself should be very wide, and raised from the street (1.5 m wide sidewalks are useless for forming a neighborhood; see Pattern 55: RAISED WALK).
13. The residents prepare designs using colored bits of scrap material not thicker than 1 cm (pebbles, tile fragments, etc.), and push them into the wet concrete as soon as the sidewalk is poured and smoothed. Anything can be used as long as it doesn’t compromise the structural integrity of the concrete. Expansion joints are incorporated as part of the design. This act personalizes one’s own bit of sidewalk, and establishes the priority of human expression over industrial forms.
14. House building can begin, carried out by the residents themselves, with the front façade going up first at the edge of the sidewalk. In this way, the urban spaces, rather than the houses themselves, are the first spatial elements to be physically constructed (Pattern 106: POSITIVE OUTDOOR SPACE).
15. The entrance (or entrances) to the settlement should be clearly defined by more prominent buildings so they are obvious points of transition (Pattern 53: MAIN GATEWAYS).
16. The government can solidify the urban space by building a large kiosk there — a roofed open room (Pattern 69: PUBLIC OUTDOOR ROOM). Make sure it has steps that are comfortable to sit on (Pattern 125: STAIR SEATS). This element can catalyze the use of the urban space, and enhances sacred elements such as a large tree.
17. Owners complete their individual houses, at their own pace. They have complete freedom in the floor plan within their original markings. If it is appropriate to the culture, build a low sitting wall or ledge integral with the front wall next to the entrance (Pattern 160: BUILDING EDGE and Pattern 242: FRONT DOOR BENCH). This, in turn, might influence the roof overhang.
18. The description of the building sequence depends on local materials availability, delivery systems, and the most economical alternatives. Decisions such as whether to pour a floor slab at the same time as the concrete sidewalk; if there is plumbing available that needs to go under the slab; whether to fill upright hollow drain pipes with concrete to make a house’s corner columns; what material to use for the load-bearing walls; whether to drop in a prefabricated toilet module; the shape of the roof and how it is to be built, are all best taken by the local consultants.
19. The consultants can advise the owner/builders on how to form the house entrance and windows. A main entrance should have drastically thickened edges to represent the transition from outside to inside (Pattern 225: FRAMES AS THICKENED EDGES). Encourage people to build a transition space, however modest (Pattern 112: ENTRANCE TRANSITION). This emphasizes entry as a process, the opposite of a front door designed as an image of a minimal discontinuity in the flat wall.
20. The same principle also applies to windows: help the owner/builders to create windows with deep reveals and a very thick frame (Pattern 223: DEEP REVEALS).
21. Perhaps the single most important rule to creating rooms in a building is that they must have natural light from two sides (Pattern 159: LIGHT ON TWO SIDES OF EVERY ROOM).
22. As the house fronts near completion, the government offers a monetary prize for the most artistic ornamentation, preferably using traditional motifs chosen entirely by the owners, and supplies paints and materials for that purpose (Pattern 249: ORNAMENT). Ornamentation should be more detailed, and more intense, at eye level and at those places where a user can touch the building.

The above proposal may appear interesting, perhaps extraordinary to conventional planners. Some will doubtlessly criticize it, even though it is supported by the most important document of Latin American planning: the “Laws of the Indies”. (Las Leyes de Indias explicitly direct that a settlement be planned around its central urban space, which has to be established first). We believe our suggestions to be applicable and we ought to try and implement them to any degree possible. It is not necessary for the builders to have access to the full description of each pattern mentioned here; a simple outline and diagram are sufficient. We list the patterns only for reference purposes. The goal of ornamentation is NOT to add something “pretty” so as to distract from the otherwise difficult living conditions. In fact, it serves to connect the residents in a deeper sense to their environment, by giving them intellectual ownership of the physical structure. For this reason, it is absolutely necessary that the residents themselves generate all the ornament and create it with their own hands.