Masterplan Design

Masterplan Design Skill

Generate complete urban masterplans from site understanding through spatial structure, land use distribution, street network, block layout, density strategy, phasing plan, and implementation framework. This skill orchestrates multiple specialized sub-skills into a coherent design process that produces a fully resolved masterplan at any scale from a single city block to an entire new district or town extension.

1. Masterplan Design Process

The masterplan design process follows eight sequential phases. Each phase builds upon the outputs of the previous phase. Do not skip phases; mark any phase "Deferred" with justification if the user has not provided sufficient input. Cross-skill invocations are indicated with the --> symbol.

Phase Checklist

Phase 1: Site Understanding
  [ ] Site analysis complete or provided by user
  [ ] Constraints and opportunities mapped
  [ ] Key connections to surrounding context identified
  --> invoke site-analysis if not already done

Phase 2: Vision and Program Definition
  [ ] Design vision statement drafted (1 paragraph)
  [ ] Target population and household count established
  [ ] Total GFA by use type calculated
  [ ] Character precedents identified (3-5 reference projects)
  [ ] Sustainability and resilience targets set
  --> invoke precedent-study if user requests comparable projects

Phase 3: Structuring Framework
  [ ] Movement framework established (primary routes, transit spine)
  [ ] Green-blue framework established (parks, corridors, water)
  [ ] Built form framework established (centers, edges, density gradient)
  [ ] Transect zones defined and mapped (T1-T6 as applicable)
  [ ] Framework tested against site constraints

Phase 4: Street Network Design
  [ ] Street hierarchy defined (arterial, collector, local, shared)
  [ ] Cross-sections assigned to each street type
  [ ] Key intersections and public transport stops located
  [ ] Block structure generated from street network
  --> invoke street-design for hierarchy and cross-sections

Phase 5: Block and Parcel Layout
  [ ] Block typologies selected for each Transect zone
  [ ] Block dimensions and perimeters verified against standards
  [ ] Parcel subdivision logic applied
  [ ] Building footprint envelopes tested for feasibility
  --> invoke block-and-density for typology selection and optimization

Phase 6: Land Use and Program Distribution
  [ ] Land use zones assigned to each block or parcel
  [ ] Use mix percentages verified against vision targets
  [ ] Anchor uses located (schools, community centers, retail cores)
  [ ] Ground-floor activation strategy defined for key streets
  --> invoke mixed-use-programming for use mix and allocation

Phase 7: Public Space Network
  [ ] Neighborhood park(s) sized and located (within 500 m of all residents)
  [ ] Central plaza or civic space defined
  [ ] Pocket parks and play spaces distributed
  [ ] Greenways and pedestrian corridors connected
  [ ] Public space typology and character described
  --> invoke public-space-design for parks, plazas, civic spaces

Phase 8: Phasing and Implementation Strategy
  [ ] Development phased into 3-5 stages
  [ ] Infrastructure sequencing plan completed
  [ ] Catalyst projects identified for Phase 1
  [ ] Interim use strategy for undeveloped parcels defined
  [ ] Governance and delivery mechanism outlined

2. Structuring Framework Methodology

The structuring framework is the spatial DNA of the masterplan. It establishes the primary organizing systems before any building is placed. Three overlapping frameworks -- movement, green-blue, and built form -- are developed in parallel and then overlaid to create the composite spatial structure.

Movement Framework

Establish the hierarchy of movement from regional connections down to the individual street.

1. Regional connections: identify all points where the site connects to the surrounding road network, transit system, and cycling/pedestrian paths. These are the fixed anchors of the movement framework.
2. Primary routes: draw the main streets that connect the anchor points across the site. These carry the highest traffic volumes, public transit lines, and utility trunk infrastructure. Typical right-of-way: 24-36 m. Align with topography to minimize grading. Avoid routing through sensitive ecological areas.
3. Transit spine: if the site warrants transit (population >5,000 or area

   20 ha), designate a transit corridor. Locate stops at 400-600 m intervals (5-minute walk catchment). Orient the highest density and mixed-use development toward transit stops.

4. Secondary routes (collectors): connect primary routes, creating the block structure. Typical right-of-way: 18-24 m. Distribute traffic across multiple routes to avoid bottlenecks.
5. Local streets: provide direct frontage access to buildings. Typical right-of-way: 12-18 m. Design for low speeds (30 km/h or less). Consider shared surfaces in residential areas.
6. Pedestrian priority zones: designate areas where pedestrians have primacy over vehicles -- the town center, market streets, school zones, waterfront promenades. These may be fully pedestrianized or designed as woonerven.
7. Cycling network: provide a connected cycling network that links to the citywide system. Protected cycling facilities on primary and secondary routes. Shared lanes acceptable only on local streets with speeds below 30 km/h.

Green-Blue Framework

Establish the network of open spaces, ecological corridors, and water management systems.

1. Natural features: map all existing natural features -- waterways, wetlands, significant tree stands, ridgelines, steep slopes (>15%). These are the non-negotiable anchors of the green-blue framework. Protect them with appropriate buffers (minimum 15 m from waterways, 10 m from significant trees).
2. Stormwater management: design the stormwater system as a visible amenity, not buried infrastructure. Use the natural drainage direction to locate bioswales along streets, rain gardens in blocks, and detention basins as park features. Target: detain the first 25 mm of rainfall on site.
3. Park hierarchy: apply a three-tier system:
   • District park (2-10 ha): one per 10,000-20,000 residents, sports fields, playgrounds, passive recreation, community gardens.
   • Neighborhood park (0.5-2 ha): one per 3,000-5,000 residents, within 500 m walk of all dwellings. Playground, seating, lawn, shade trees.
   • Pocket park / plaza (0.05-0.5 ha): one per 500-1,000 residents, within 200 m walk. Seating, planting, public art, play elements.
4. Green corridors: connect parks and natural areas with linear green spaces at least 10 m wide. These serve as ecological corridors, pedestrian and cycling routes, and stormwater conveyance. Align with street tree planting to create a continuous urban canopy.
5. Urban ecology: target 30% tree canopy cover at maturity. Specify native species for at least 70% of plantings. Create habitat diversity: meadow, woodland, wetland, hedgerow.

Built Form Framework

Establish the three-dimensional organization of buildings and spaces.

1. Centers and edges: identify the center(s) of the masterplan -- the point(s) of highest intensity, typically at the intersection of primary routes or at transit stops. Define the edges -- the boundaries where the development meets its surroundings. Edge treatment must mediate between the new and existing.
2. Density gradient: density should peak at the center and decrease toward the edges. This creates a legible spatial hierarchy and concentrates activity where accessibility is highest. Apply a smooth gradient, not abrupt steps.
3. Building height strategy: height reinforces the density gradient. Tallest buildings at the center, stepping down toward edges and sensitive adjacencies. Define maximum height zones. Ensure that tall buildings do not overshadow public spaces for more than 50% of daylight hours at equinox.
4. Special sites: identify locations for landmark buildings (civic, cultural, religious), gateway buildings (marking entry points), and terminated vista buildings (closing axial views). These sites receive special design attention and may have different height or setback rules.
5. Street wall and setback: define the default building line for each street type. Primary streets: build-to line at the property boundary to create a continuous street wall. Local residential streets: may have a 3-5 m setback for front gardens. Parks and waterfronts: buildings face the open space with active ground floors.

The Transect as Organizing Principle

The Transect provides a gradient of human habitat from rural to urban core. Apply the following zones, selecting those appropriate to the project scale and context.

How to apply the Transect:

1. Identify the center(s) of the masterplan -- these are T5 or T6.
2. Define zones radiating outward from the center, transitioning smoothly through T4, T3, and (if applicable) T2 and T1.
3. Each zone receives the appropriate density, height, street types, use mix, and building typologies from the zone specification.
4. Transitions between zones should occur at natural boundaries -- parks, streams, major streets -- not in the middle of a block face.

3. Design Parameter Ranges

The following table provides context-sensitive parameter ranges for key design metrics. Select the appropriate row based on the site's intended character and position in the urban hierarchy. All ranges are indicative; local codes and market conditions may require adjustment.

Primary Parameter Matrix

Secondary Parameters

Use Mix Targets by Context

4. Design Generation Logic

When generating a masterplan, follow these twelve steps in order. Each step has a defined input, process, and output. Do not proceed to the next step until the current step is resolved.

Step 1: Map Constraints

Input: Site boundary, topographic data, existing infrastructure, regulatory information, environmental data from Phase 1 site analysis.

Process: Create a composite constraint map by overlaying:

• Site boundary (hard boundary -- nothing outside this line)
• Topography: slopes >15% are designated unbuildable open space
• Flood zones: 100-year flood plain is designated for open space or stormwater infrastructure only; no habitable structures below base flood elevation
• Protected features: heritage structures, significant trees (DBH >30 cm), ecological habitats, archaeological sites
• Infrastructure easements: utility corridors, pipeline setbacks, power line easements (typically 15-30 m)
• Regulatory setbacks: from adjacent properties, roads, watercourses
• Contamination: brownfield areas requiring remediation before development

Output: A constraint map showing buildable area, partially constrained area (buildable with mitigation), and unbuildable area. Calculate net developable area = gross site area minus unbuildable area.

Step 2: Identify Connections

Input: Constraint map, surrounding street network, transit routes, existing pedestrian and cycling paths, adjacent land uses.

Process: Mark every point where the site can connect to the surrounding context:

• Existing streets that terminate at the site boundary (mandatory connections)
• Potential new street connections that align with the surrounding grid
• Transit stops or stations within 800 m of the site boundary
• Pedestrian and cycling paths that reach the site boundary
• Visual connections: views into or out of the site that should be maintained

Output: A connection map showing all mandatory and optional connection points, classified by mode (vehicular, pedestrian, cycling, transit, visual).

Step 3: Establish Primary Movement Structure

Input: Connection map, constraint map, target population (from Phase 2).

Process: Draw the primary streets that connect the most important connection points across the site. These are the bones of the masterplan.

• Connect opposite sides of the site to ensure through-movement and integration with the surrounding fabric (avoid cul-de-sac plans unless topography demands)
• Align primary routes with topography to minimize grading costs
• If the site warrants transit, designate the transit corridor as a primary route
• Primary routes should pass through or adjacent to the intended center(s)
• Target 2-4 primary routes for a 20-50 ha site; 4-8 for sites over 50 ha

Output: Primary movement structure showing 2-8 main routes with approximate alignments and connection points.

Step 4: Define Centers

Input: Primary movement structure, transit stop locations, site analysis (views, solar orientation, existing features).

Process: Locate the center(s) of the masterplan -- the point(s) of highest density, activity, and urban intensity.

• Place the primary center at the intersection of primary routes, ideally at or near a transit stop
• For sites over 30 ha, consider a secondary center or neighborhood node
• The center should be on the most accessible part of the site (fewest topographic barriers, best connections to surroundings)
• Avoid placing centers on site edges unless the edge is a significant public amenity (waterfront, major park, existing high street)
• Size the center based on target population: 0.5-2 ha for 2,000-5,000 residents; 2-5 ha for 5,000-15,000; 5-10 ha for 15,000-40,000

Output: Center locations with approximate extent, intended character, and relationship to primary movement structure.

Step 5: Lay Out Secondary Street Network

Input: Primary movement structure, center locations, block size targets from the parameter matrix (Section 3).

Process: Draw secondary streets (collectors) that connect primary routes and create the block structure.

• Target block perimeters from the parameter matrix: shorter blocks near the center (250-350 m), longer blocks at edges (400-600 m)
• Ensure all blocks have at least two street frontages
• Align streets to maximize solar access: in the northern hemisphere, east-west streets create south-facing building frontage; north-south streets create morning and afternoon sun
• Create T-intersections rather than four-way intersections where possible (they slow traffic and create terminated vistas for landmark buildings)
• Ensure the street network provides multiple route choices (connectivity index target: at least 1.4, meaning 40% more links than nodes)

Output: Complete street network with block structure. All blocks should be labeled or numbered for reference.

Step 6: Establish Density Gradient

Input: Street network, center locations, Transect zone definitions (Section 2), parameter matrix (Section 3).

Process: Assign a Transect zone (T3-T6) to each block based on its distance from the center and its adjacency conditions.

• Blocks at the center: T5 or T6 (highest density, tallest buildings, full mixed-use)
• Blocks one ring out from center: T4-T5 (medium-high density, mixed-use transitioning to residential)
• Blocks at the site edge: T3-T4 (medium density, predominantly residential, responding to adjacent character)
• Blocks adjacent to sensitive edges (parks, heritage areas, low-rise neighbors): T3 maximum to ensure transition
• Blocks along transit corridors: T4-T5 regardless of distance from center

Output: Density plan showing Transect zone assigned to each block, with corresponding FAR, height, and coverage parameters.

Step 7: Size and Locate Blocks

Input: Density plan, block typology catalog from block-and-density skill.

Process: Assign a specific block typology to each block.

• Select the block typology that matches the assigned Transect zone
• Verify that the block dimensions accommodate the typology (e.g., perimeter blocks need minimum 50 m face-to-face width for adequate courtyard)
• Adjust block dimensions if necessary by shifting street alignments (secondary streets have more flexibility than primary routes)
• Ensure parcelization works: each block should be subdivisible into parcels that are independently developable

Output: Block plan with typology assigned to each block, block dimensions verified, and parcelization logic indicated.