# Jane Jacobs Mixed Use Analysis > Evaluate how the separation or combination of uses (residential, commercial, industrial, civic) affects street life and neighborhood vitality. - Skill: `sethmblack/jane-jacobs-mixed-use-analysis` (Agent Skill) - Install (CLI): `npx skillmds add sethmblack/jane-jacobs-mixed-use-analysis` - Raw SKILL.md: https://api.skillmd.com/api/skills/sethmblack/jane-jacobs-mixed-use-analysis/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: sethmblack (https://skillmd.com/u/sethmblack) - Updated: 2026-09-08 - Page: https://skillmd.com/skills/sethmblack/jane-jacobs-mixed-use-analysis --- # Mixed-Use Analysis Evaluate how the separation or combination of uses (residential, commercial, industrial, civic) affects street life and neighborhood vitality. --- ## When to Use - Evaluating a zoning proposal or development plan - Someone asks "Why is this area dead?" or "Why doesn't this work?" - Analyzing whether to approve single-use vs. mixed-use projects - Diagnosing a neighborhood that was "planned" but fails - Comparing why one district thrives while a similar one languishes - Any decision about separating or combining land uses - When "highest and best use" arguments ignore diversity --- ## Inputs | Input | Required | Description | |-------|----------|-------------| | area | Yes | The district, neighborhood, or development to analyze | | proposed_uses | No | What is being proposed (for prospective analysis) | | current_uses | No | What currently exists in the area | | hours_observed | No | Activity patterns observed at different times | | zoning_context | No | Current zoning restrictions or proposals | --- ## The Mixed-Use Framework Jane Jacobs identified mixed primary uses as the first of her four generators of urban diversity. Single-use zoning—separating where we live, work, shop, and play—creates areas that die when their one purpose isn't active. Mixed uses create all-day vitality. ### Core Principles **"Districts must serve more than one primary function; preferably more than two."** - The fundamental requirement for street life. **"Diversity of uses creates diversity of users."** - Different uses bring different people at different times for different purposes. **"The more successfully a city mingles everyday diversity of uses and users in its everyday streets, the more successfully, casually (and economically) its people thereby enliven and support well-located parks."** - Mixing enables everything else. --- ## The Analysis Process ### Step 1: Map Primary Uses Identify what brings people to this area: | Use Category | Examples | Typical Active Hours | |--------------|----------|---------------------| | Residential | Apartments, houses | Evenings, early mornings, weekends | | Office | Professional services, government | 9 AM - 5 PM weekdays | | Retail | Shops, restaurants, services | 10 AM - 9 PM, varies | | Industrial/Maker | Manufacturing, workshops | Varies by industry | | Civic | Libraries, schools, churches | Scheduled programming | | Entertainment | Theaters, bars, venues | Evenings and weekends | **Key Question:** "What primary functions bring people here, and when?" ### Step 2: Chart the Hours of Activity Map when each use generates presence: ``` Hour Residential Office Retail Civic Entertainment 6 AM +++ - - - - 9 AM + +++ + ++ - 12 PM + +++ +++ ++ - 3 PM ++ +++ ++ +++ - 6 PM +++ - ++ + ++ 9 PM ++ - + - +++ 12 AM + - - - + ``` **Key Question:** "Are there dead hours when no primary use is active?" ### Step 3: Identify Dead Zones and Dead Hours Find the gaps: - **Dead Zones:** Areas dominated by single uses that shut down - **Dead Hours:** Times when no primary use generates activity - **Dead Frontage:** Ground floors that don't engage the street (parking, blank walls) **Key Question:** "When and where does life disappear?" ### Step 4: Assess Use Complementarity Evaluate whether uses support each other: - Do residential and office uses share lunch spots? - Do evening uses keep streets alive after offices close? - Do weekend uses activate weekday-only areas? - Do different users create continuous presence? **Key Question:** "Do uses hand off activity to each other through the day?" ### Step 5: Diagnose and Prescribe Based on the analysis: - What uses are missing? - What hours need coverage? - What would complement existing uses without competing? - How can mixing be introduced without displacement? **Key Question:** "What's needed to achieve all-hours activity?" --- ## Output Format ```markdown ## Mixed-Use Analysis ### Area Analyzed [District, neighborhood, or development] ### Primary Uses Inventory | Use | Presence | Hours Active | Coverage | |-----|----------|--------------|----------| | [Type] | [Strong/Moderate/Weak/Absent] | [Time range] | [% of area] | ### Activity Heat Map | Hour | Mon-Fri | Sat-Sun | Primary Driver | |------|---------|---------|----------------| | 6-9 AM | [Level] | [Level] | [What use] | | 9-12 PM | [Level] | [Level] | [What use] | | 12-3 PM | [Level] | [Level] | [What use] | | 3-6 PM | [Level] | [Level] | [What use] | | 6-9 PM | [Level] | [Level] | [What use] | | 9-12 AM | [Level] | [Level] | [What use] | ### Dead Zones and Dead Hours **Dead Hours:** [Times when activity collapses] **Dead Zones:** [Specific areas that die] **Dead Frontage:** [Ground floors that don't engage] ### Use Complementarity Assessment | Use Pair | Relationship | Gap/Opportunity | |----------|--------------|-----------------| | [Use A + Use B] | [Complement/Compete/Ignore] | [What's missing] | ### Diagnosis [Why this area has the vitality it does—or doesn't] ### Prescriptions for Mixing | Missing Use | Would Cover | Integration Strategy | |-------------|-------------|---------------------| | [What's needed] | [Hours/Days it would fill] | [How to add it] | ``` --- ## Constraints - **Mixing is not random.** Uses must complement, not just coexist - **Primary uses matter most.** Secondary uses follow primaries - **All-hours is the goal.** Partial coverage creates partial life - **Ground floors are decisive.** Upper-floor mixing helps less than ground-floor mixing - **Avoid false diversity.** Ten restaurants is single-use, not mixed-use - **Proximity matters.** Uses must be close enough that users cross paths --- ## Example **Input:** "We're planning a new transit-oriented development around our commuter rail station. The developer wants mostly residential with some ground-floor retail. Will this work?" **Output:** ## Mixed-Use Analysis ### Area Analyzed Proposed transit-oriented development, 12-acre site adjacent to commuter rail station ### Primary Uses Inventory (Proposed) | Use | Presence | Hours Active | Coverage | |-----|----------|--------------|----------| | Residential | Strong | 6-9 AM, 6 PM-12 AM | 85% (floors 2-6) | | Retail | Moderate | 10 AM - 8 PM | 10% (ground floor) | | Office | Absent | N/A | 0% | | Civic | Absent | N/A | 0% | | Entertainment | Weak | Evening | 5% (one restaurant) | ### Activity Heat Map (Projected) | Hour | Mon-Fri | Sat-Sun | Primary Driver | |------|---------|---------|----------------| | 6-9 AM | Medium | Low | Residents leaving for work | | 9-12 PM | Low | Low | Retail shoppers (few) | | 12-3 PM | Low | Medium | Retail, weekend residents | | 3-6 PM | Low | Medium | Retail, residents returning | | 6-9 PM | Medium | Medium | Residents home, restaurant | | 9-12 AM | Low | Low | Residents only | ### Dead Zones and Dead Hours **Dead Hours:** 9 AM - 5 PM weekdays. Residents commute out; retail alone cannot sustain activity. **Dead Zones:** Interior courtyards face residential (no activation). Station plaza lacks programming. **Dead Frontage:** Parking garage entrance dominates one full block face. ### Use Complementarity Assessment | Use Pair | Relationship | Gap/Opportunity | |----------|--------------|-----------------| | Residential + Retail | Weak complement | Residents commute out; can't support daytime retail | | Residential + Office | Missing | No daytime population to use retail, watch streets | | Station + Development | Ignore | Commuters pass through, don't stay | | Retail + Entertainment | Weak | One restaurant insufficient for evening destination | ### Diagnosis This development repeats the classic TOD mistake: residential density without daytime activity. The 85% residential program means the site empties every weekday from 9-5 as residents commute OUT. The ground-floor retail will struggle without daytime customers. The station brings commuters who leave, not visitors who stay. By 10 AM on a Tuesday, this will feel like a ghost town despite its density. ### Prescriptions for Mixing | Missing Use | Would Cover | Integration Strategy | |-------------|-------------|---------------------| | Office (15-20% of development) | 9 AM - 5 PM weekdays | Replace one residential building with office; workers support retail, provide eyes | | Civic (library branch, community space) | Afternoons, weekends, evenings | Ground floor of residential building; programming draws diverse users | | Childcare | 7 AM - 6 PM weekdays | Near station for drop-off; parents + staff add daytime presence | | Maker/Workshop space | Varied hours | Affordable space in "aged" portion if any; different rhythm than office | **Critical recommendation:** Reduce residential from 85% to 60%. Add 20% office, 10% civic, 10% ground-floor active uses. The station's commuters should arrive TO this place, not depart FROM it. A TOD that sends its residents away and receives no one in return is single-use development with a train. --- ## Integration This skill is part of the **Jane Jacobs** expert persona. It applies Jacobs's first generator of diversity from *The Death and Life of Great American Cities*—the requirement for mixed primary uses. For related analysis: - Use **street-level-observation** to see what's actually happening now - Use **eyes-on-the-street** to assess how mixing affects safety - Use **emergent-order-recognition** to find self-organizing patterns in existing mixed areas