NGO and community action on housing

Consolidation of informal housing

Informal settlements are not fixed: over time residents consolidate them. A shelter of scrap materials is gradually rebuilt in brick and concrete, roofs are improved, extra rooms or floors are added and businesses open as savings allow. Consolidation speeds up when residents have security of tenure (they will not be evicted), so they are willing to invest; governments can help with legal titles, small loans and basic services (site and service schemes provide plots with water and drainage on which people build their own homes). The Getting Started Guide lists land tenure security, incremental housing finance and NGO-community partnerships.

Case study: Orangi Pilot Project, Karachi

The Orangi Pilot Project (OPP) in Orangi, a large informal area of Karachi, Pakistan, helped residents build their own sanitation (IIED):

• Engineers had said sewers clogged; the fix was a small septic tank at each toilet so only liquid entered the sewers.
• The target cost was 240 rupees, compared with a minimum of 2,400 rupees for a conventional septic tank per toilet.
• Internal development: households financed, built and managed lane sewers themselves, lane by lane. External development: government built trunk sewers and disposal points.
• By 2016, residents had invested 168 million rupees in Orangi's 7,280 lanes, and the model had spread to 651 other urban locations (77,859 households) and to villages.

It shows that community action can cut costs and give residents ownership, but needs the state to provide the big infrastructure.

NGOs and community groups in developed cities

In developed cities, housing associations, cooperatives, community land trusts and charities provide affordable housing, often for people the market excludes (key workers, the homeless, older people). They may buy land collectively to keep homes affordable permanently, or renovate empty buildings. Advantages: local knowledge, community control, long-term affordability. Limitations: small scale compared with need, dependence on grants and access to land.

Worked example

Compare the OPP target cost per toilet with the conventional septic tank cost.

1. Conventional: 2,400 rupees. OPP target: 240 rupees.
2. Ratio = 2,400 / 240 = 10.
3. Saving = 2,160 rupees, which is 90% cheaper.

Answer: The OPP design cost one-tenth of the conventional design: a 90% saving.

Check yourself

1. By what percentage was the OPP target cost (240 rupees) lower than the conventional cost (2,400 rupees)?
   Show answer

   90 %. (2,400 - 240) / 2,400 x 100 = 90%.

2. Residents invested 168 million rupees in 7,280 lanes in Orangi. What was the average investment per lane, to the nearest rupee?
   Show answer

   23077 rupees. 168,000,000 / 7,280 = 23,077 rupees.

3. Why does security of tenure speed up the consolidation of informal housing?
   • It makes houses cheaper to demolish
   • Residents will invest in improvements if they know they will not be evicted
   • It stops people building
   • It brings in large developers
   Show answer

   Residents will invest in improvements if they know they will not be evicted. Secure residents improve their homes.

4. In the Orangi model, who built the lane sewers ('internal development')?
   • A foreign construction company
   • The national army
   • The residents of each lane
   • Nobody: sewers were not built
   Show answer

   The residents of each lane. Households financed, built and managed them.

5. A site and service scheme provides
   • plots with basic services on which people build their own homes
   • finished high-rise flats
   • free cars
   • gated communities
   Show answer

   plots with basic services on which people build their own homes. People build incrementally on serviced land.

6. Explain one limitation of community self-help schemes for improving slum housing.
   Show answer

   They are small in scale and depend on residents' savings and labour, so very poor households may not afford to take part, and they still need the government to provide large infrastructure such as trunk sewers and water mains.. Scale, resources, dependence.

Practise with instant feedback Print this lesson

Sources

• Pearson Edexcel International Advanced Subsidiary/Advanced Level in Geography specification, Issue 3 (September 2025)
• IIED: Delivering low-cost, high quality sanitation at scale (Orangi Pilot Project)
• Pearson IAL Geography Getting Started Guide

Last updated 8 November 2026. Spotted a mistake? Tell us.