Ladder

The Way Up

Stairs should overcome not only uneven levels but also challenges of a different kind. The toughest puzzle in the design of a building is the staircase between two floors. The space under the stairs is often of little use. At the top end there is no floor, there is a stairwell. A staircase thus claims space on two floors. In addition, at both ends circulation space is required to access the first step. These circulation spaces make the layout even more complicated.



This house shows exactly what is needed when making a staircase. At the times when both houses still had only one storey, ground floor, things were easy. In the corner of the houses sits a well. In order to gain access to the roof, stairs were built. The only feasible location was the edge of the well. The stairs should be closed at the underside, as dirt would otherwise fall from the steps into the well. The same applies to the red hand railing.

Once a storey was added, a stair was needed to access the next roof. That second stair was nearly impossible. An additional piece of roof was added to provide a landing to the new roof. It doubles as a canopy along the façade.

It is tempting to puzzle on the next storey.

Slum, the Vernacular Architecture of Swelling Cities

The other way around

The slum phenomenon is so widespread that we may speak of a trend in architecture. The architectural debate will not go there often, there are no glossy magazines, no coffee table books and no architecture institutions which promote its design and style, but time is certainly ripe to look at the ways of building that provide housing to more than one billion people. This chapter is about the conditions under which slums arise, the place of this style in architectural theory and the relevance to the design profession.


Photo 1. Dharavi, Mumbai, India, nicknamed 'Asia’s largest slum'.

Slum develops during high urbanization. The influx of labour from the countryside to the city goes far beyond the housing and absorption capacity of the city. Industrialization is a powerful driver of urbanization. During the industrial revolution, many slums emerged in Western cities. In factory towns, people lived in high density under miserable conditions. This side effect of the industrial revolution was overcome by introducing legislation that set conditions on the quality of housing. In addition, many manufacturers took the initiative to organize a good home for their employees.


Violence is another major cause of migration. Besides the flow of migrants from rural to urban, migration of refugees is a major cause of slums. One difference between these two migrant groups is that people in the first group choose to migrate on a chosen moment, while the second group is at one time forced to leave, due to circumstances. This displacement results from natural disasters or human violence. Volcanic eruptions, floods, and wars drive people from their homes. If the house is not already destroyed, a life-threatening situation is reason enough to migrate. By its nature, the forced displacement of a refugee means that a part of the acquired property cannot be brought in the migration. In the hurry, refugees take all that can be taken. A rural migrant for that matter, has a better starting position. Possessions can be taken and acquired assets can be sold. The motive for economic migration is the lure of the city. Refugees act from the motive of expulsion.

A third stream of migrants that feeds slum formation, is caused by deportations. These forced migrations are actually a combination of the previous two forms. Under its segregation policy, the apartheid regime in South Africa forced many native Africans to leave their territory. They came up in townships like Soweto near Johannesburg and the Cape Flats in Cape Town. Under the same regime, many forced removals to the so-called ‘homelands’ took place, which have led to acute overcrowding.

In architecture, a distinction is made in style architecture and vernacular architecture. The latter is also known as folk architecture. Modern and progressive architecture are usually considered style architecture, whereas regionalism and traditionalism belong to the vernacular architecture group. Stewart Brand points out that, “in terms of architecture, vernacular buildings are seen as the opposite of whatever is ‘academic,’ ‘high style,’ ‘polite.’ Vernacular is everything not designed by professional architects – in other words, most of the world’s buildings.”1 This description covers slum architecture fully. Meanwhile, slum is a contemporary phenomenon that occurs worldwide. One might think it is a fashion phenomenon.

A much-quoted dictum of Henry Glassie states that, “a search for pattern in folk material yields regions, where a search for pattern in popular material yields periods.”2 Styles in architecture are often indicated by a period of a particular style in vogue. Victorian, Tudor, Romanesque, colonial. Periods can also be named after trends in philosophy such as Renaissance, Constructivism, Modernism, Postmodernism, and Deconstructivism. Vernacular architecture can be characterized by region. Vernacular architecture reflects the particular local conditions, materials, and techniques. The indication by region is an appropriate way to appoint the unique combination of circumstances. Examples are Mediterranean, Santa Fe, New England, and Tuscan.

The architecture in a slum is determined by local conditions and therefore counts as vernacular architecture. Style motives play no role. At the same time, slum architecture is less recognizable than the current known regional vernacular architecture. The way to build in slums seems to be the same everywhere around the world. A high-density urban environment has far fewer variations in landscape, which indeed leads to the regional recognition of vernacular architecture. The universal urban slum environment gives its architecture a globalized nature. The urbanized area is the landscape itself. The global theme of the rapid urbanization is the local condition of which slum is the vernacular architecture. This can be found especially where the pace is very high, as in swelling cities.



Photo 2: Globalised architectural features in both Mumbai...
and


Photo 3: ...Tokyo, a striking universal element is the blue tarp, which threatens to displace corrugated steel as the icon of the shantytown.

With Glassie’s statement ‘a search for pattern in popular material yields periods’ in mind, a different conclusion can be drawn. Slum occurs in a certain stage of industrial development of a country. The combination of apparent popularity and apparent period would normally reflect an architectural style. Yet that seems not correct. It is not a matter of fashion, philosophies, or imitation of aesthetic motifs. They are local economic and social developments geographical that start slum formation at one time. The global context of the swelling cities leads to uniformity of regional aspects. Despite the apparent resemblance between slums in the world, the architecture is therefore a vernacular architecture.

There have been many studies on economic, sociological, social geographical and anthropological aspects of slums. There are already many plans made by architects for improvements in slums. Experience shows that the scale of improvement plans are of major influence on the ultimate success. Large-scale plans appear more likely to fail than small-scale ones. The piecemeal approach better accommodates the intricate reality of the built environment in which social and economic structures together constitute the urban phenomenon.

Opposite the large amount of studies and policies is the lack of proper documentation of architecture in slums. Accurate knowledge of local building methods may give clues to good development programs. Many ideas on improving the living conditions of slum dwellers are based on replacement building by developers. Regardless of the varying success of such projects, the scale of the slum phenomenon is thus large that it is necessary to address the development potential of slums directly. Slum dwellers themselves are able to build. There are conditions by which development into a fully-fledged town is blocked in such areas. Visualizing this glass ceiling is the subject of many economic, sociological, social geographical and anthropological studies. Good understanding of the potentials that are below the glass ceiling is essential for promoting development.

In addition, knowledge about slums is an interesting source for historians. The development history of cities in the industrialized countries is seen in living form in the swelling cities. The initial symptoms of an urbanizing society reveal the origins of urbanism. The style of building can be seen as the beginning of architecture. The accumulation of techniques gives insight in the profession of engineers.

"The sending of cookbooks to a country suffering famine", is used as a metaphor for the effectiveness of making architectural plans for slums. In that analogy, as it is better to provide food aid that is tailored to the local gastronomy, plans that are based on the local way of building have a much better chance than externally imposed schemes. Knowledge of construction in slum areas is indispensible and it is important that this gap in the architecture library be filled. As one sixth of the world population lives in slums, the architecture section may look forward to a significant expansion of the bookcase.

1. Stewart Brand, How Buildings Learn, what happens after they’re built (Penguin Books USA, 1994) p 132.
2. Henrie Glassie, Pattern in the Material Folk Culture of the Eastern United States (Philadelphia: University of Pennsylvania, 1968) page 33.

Constriction by Construction

The narrowness of alleys in a slum

A city can suffer of vascular stenosis. Such terms are used when the density of traffic is clogging the roads. One speaks of a traffic infarct when an area is blocked by traffic jams. In this metaphor, the traffic is the blood in the vessels (the streets) of the city. Yet there is something wrong with this comparison. Blood vessels constrict by atherosclerosis, gradually diminishing the blood stream. In the case of the traffic infarct the cause is not a narrowing of the streets but an increase in traffic. It is congestion instead of constriction.

In Dharavi however, the narrowing is actually taking place in the imagery of vascular constriction. We can even speak of constriction by construction. Streets and lanes are narrowing down. A direct cause is the construction of tiny shops in narrow alleys that apparently are not narrow enough yet. The story in the chapter Tailor Made shows how this encroachment works.



Photo 1. An alley, no more than left over space between 'detached' houses.

When Koliwada was still an ordinary fishermen’s village, before it was overwhelmed by the new inhabitants of what is now called Dharavi, the streets had a normal size. Wide enough for two cars to pass each other. Houses were as far apart as enjoyable and necessary. Some intersections of streets were wide enough to form a square. With the population pressure increasing, the pressure to use the open space for building rose dramatically. Squares disappeared. Streets shrank to alleys.


Photo 2. An alley narrower than a normal doorway. Photo 3. Less than shoulder width.

Pedestrians can barely pass each other. It is ‘Hold your belly’ or wait until there is no oncoming traffic. An overview is hard to get in the network of alleyways and passages. An open space is an important marker and many routes through the maze can only be overseen by remembering which space is connected to another open space through which alley. The trouble is of course that it is a natural temptation to fill a large open space with building. To get an impression of the original width of streets and squares, it helps to distinguish the age of buildings. Doing so we see what was already there and what was built later. Insight is improved by recognizing that order. By imagining the moment a particular building did not yet exist, we get an impression of what were once the normal dimensions of public space. In the following three pictures, the big pink house in the background is what was already there.



Photo 4. Three photos of one building. With this kind of infill, open spaces disappear leaving a network of alleys only.


Clearly the gray house in the foreground was added later. It is hardly two meters wide and maybe four meters deep. The front door is covered with a blue curtain with red and yellow flowers. The stairs to the room above it are on the outside. Perhaps the upper chamber is a separate dwelling. The lacquered wooden door with the blue frame is the original door of the big pink house. The green door on the first floor is also part of the big pink house. The stairs serve both the top floor of the old house and the upper chamber of the newer house. Thinking about the order of building it could well be that the ladder was already there before the new house was built, as the first floor of the pink house had to be accessible anyway. Considering the big pink house only, the first floor is probably also added in a second stage. Therefore the stairs are outside, next to the door. It is no use to build steps right in your living room and not in front of the door either. And so on. Thus the time factor makes the logic behind this seemingly irrational compositions transparent. To get the picture of the original wider streets, just imagine that last built grayish house not being there. This once was a village with very normal streets.

A less obvious reason for the narrowing of the streets is the adding of floors on top of existing houses. Stairs play the leading role in this. The upper floor needs access of course and therefore steps are necessary. Designing a staircase is a puzzle in itself, as described in the chapter Ladder.



Photo 5. Sophisticated staircase, wrapped around the corner of the groundfloor dwelling.


Photo 6. The house on the right is extended over the alley. The columns and overhang form an arcade.

The roof is a convenient place to expand a house. Land costs do not apply and the floor is already there. Only four walls and a roof are needed, and steps to get upstairs. There are two options for the location of the stairs. Inside the existing house or outside. Stairs inside come with a few objections. A staircase takes space while the intention was to gain additional space. Also a stairwell should be made in the existing roof, which requires many additional structures. With the cutting out of the stairwell, space is lost on the floor upstairs. An internal staircase is expensive and causes a loss of space on both floors. A staircase on the outside doesn’t have such drawbacks. The existing house remains untouched. And a big advantage is the independence of the new floor. It has the potential to be rented or sold as a private entrance available. An outside staircase is thus a very sensible choice.
Therefore, with the addition of a floor usually comes a staircase outside the house.



Photo 7. Steps halve the passageway.
Photo 8. The alley gradually becomes a tunnel.

These stairs, of course still requires space but in this solution it is at the expense of public space and not of their own space. The increasing number of stairs reduces the capacity of the alleys. In some situations, placing stairs is virtually impossible. And although it may sometimes look messy, the ingenuity of the builders deserves appreciation.



Photo 9. The (left) ladder’s the lower half is narrower, in favor of the traffic space in the alley.


Photo 10. The passage on the street remains usable by clever use of a platform top.


Photo 11.The elevated ground floor (convenient in case of flooding) is used as an impetus for the stairs.



Photo 12. Two photos showing two directions in one alley. The neat pavement and the overhanging first floors turn the space into a room on its own.

The additional floor on the house is often built as a cantilever. The new floor sticks out over the alley. This provides additional space on the first floor and creates a kind of ceiling in the alley. Besides the benefits to the alley, like shelter from sun and rain, there are disadvantages as well to the quality of the houses. In their growth upwards, the houses also grow closer to each other which is detrimental to the entry of light and air. Also privacy suffers considerably. Besides clean water and sanitation, privacy is a scarce article.

On the Edge

Crossing Borders

Contrasts make things visible. Contrasts occur mainly at the boundary of an object, a house or a neighbourhood. Right at the edge of a slum, its particularities compared to the surrounding area are clearly visible.

In the informal society of slum dwellers, every building is an accumulation of improvements. Because of the risk of destruction, investments are kept to a minimum. Investments that yield long-term returns are impossible. The strength of formal property lies in the time factor. The certainty that a longer time is available to recover the incurred development costs, it is possible to spread those costs. When demolishing a building to make way for new construction, the residual value, the potential yield and the demolition costs are amortized. These costs can be generated from the future returns. In the informal economy demolition is an unattractive option. Distribution of costs on future returns is not possible. The lack of formal ownership annihilates guarantee about the time factor. Replacement of a building by something better is much less common than adapting a building to the changed needs. So houses clearly look like a stack of improvements and extensions.


Photo 1. Slum as stacked improving, behind it improved stacking.

The formal sector of society has the ability to accumulate capital. People bring their money to the bank for interest and have a guarantee that they are entitled to their assets. The bank can provide credit to investors and developers thus facilitating property to be developed. Like in the case of high-rise houses that can only be achieved with accumulated capital and can only yield profit on the long-term. The informal sector lacks this ability to accumulate.

The encounter of these two worlds, the formal and the informal, can be very sharp but also very diffuse. Sharp in the appearance of these buildings. Diffuse in the use of space. Owners find themselves protected by formality, squatters are informal and are at risk of destruction of their shelter. In the slum, informal and formal are being built against each other or even stacked. A shop is illegally built against a house in the formal sector, with the consent of the formal owner. An owner rents his roof to an illegal migrant. A migrant family is meanwhile legalized by a law but their house is in an illegal spot. Srinanda Sen and Jane Hobson observed that, “Under a resolution passed by the government of Maharashtra, slum dwellers that have lived in the city prior to 1995 are recognised as legitimate dwellers who are entitled to resettlement if evicted. Thus it’s a paradox that the people are legitimate but the slum in which they live is unrecognised and so merits no services.” .1


Photo 2. Encroachment on land owned by the railways.

Railway companies are big land owners and the battle for space in the city will always occur along railways. Not only the land on which the tracks lay, are part of the property. Usually a strip of land on either side of the track is in the possession of the railway, for future rearrangement or doubling of the tracks. Then if the pressure to build houses is very high, that empty spare land along the railroad becomes very tempting. The land of the railway is a lucrative business. In many countries, this reserved land is temporarily leased out or built upon by the railway itself. The revenues are substantial. The rental of land and buildings makes the railway companies an important party on the property market.


Photo 3. Railway land used to grow herbs.

It is understood that the land ownership of the railway property is thoroughly formally stated. A state with statutory ownership in the formal society is at little risk of a successful land theft. However, when that property is attacked by the informal society, matters become more complex. The unregistered, informal, sublegal, extralegal, and illegal migrants are invisible to the administration of the formal and therefore difficult to fight. They cannot be sued or addressed with an eviction notice. Only the use of force would help but leaders rarely become popular by doing so.

Besides the advantage of the invisibility enjoyed by illegal builders, the railways have a physical disadvantage. Their territory is narrow and elongated, the boundaries of their area is above average length. These long land borders are difficult to defend. When the railways clear illegal constructions in their fields, there will be replacements within a very short time. The shacks are very easy to build quickly. The rebuild rate can be huge. A shelter that has been destroyed in the afternoon will stand again the next morning. In Turkey, such dwellings are therefore called Geçekondus (“Set up overnight”). The daily cycle of evacuation and reconstruction can keep going for consecutive months. Persistence wins but the victory has a limited shelf life. This cat and mouse game makes life in the land strips along the track always uncertain. An increased risk of destruction always remains and it keeps the buildings from growing.


Photo 4. The closer to the railways (foreground), the more improvised the building.

There is safety in numbers means that the chance to become victim of something becomes smaller as the group increases. In a flock, birds flying in the heart of the swarm are least likely to be caught by a bird of prey. Therefore, it is relevant to fly in a swarm and preferably not on the edge. This instinct also explains the apparent behaviour of a swarm as a body. When each individual adheres to the swarm and escapes outside threats by flying to the heart of the swarm, the flock as a whole creates the typical forms and movements of the swarm. A school of fish moves with the same regularity. Of course, houses in a slum cannot swarm in that dynamic way. However, it explains why houses on the edges of the slum are often smaller than in the middle. The risk of destruction is greater to the edges. As can be seen in building along the railway, violating a formal property is a risk-increasing factor. Besides that, the physical situation also plays a role. The houses on the edge of a slum are simply easier to reach for bulldozers. In the heart of the slum the risk of destruction is smaller and the willingness to invest is subsequently more.


Photo 5. A wall as a clear demarcation of the railway property. Security for both parties.

A wall between the formal property of the railways and the slum reduces the risk of destruction. It is less attractive to live behind a wall outside the residential area, which is ensuring the railways’ property rights not being violated. In return it is unlikely that bulldozers get to the slum via the railway site. The houses along this border are therefore of reasonable quality, investing is less risky, the risk of destruction is notably small. The wall creates an ideal dump location, making it easy to keep the street on the slum side clean.


Photo 6. An old recipe: water provides protection against invasions.

A moat has always been an excellent defense and therefore building along this river is a fairly safe investment. The area left of the river is Thirteenth Compound, where the recycling industry is located. Roofs are used as storage for merchandise. The houses on the left have exceptional facades. Ground floor and upper floors seem to be built as one project, as the facade runs in one surface over two floors. This is exceptional as it requires a significant investment in a short period. Most homes in Dharavi are an accumulation of successive investments with significant intervals. The facades of the different phases show large variations and rarely form one continuous surface.

The river flows into Mahim Creek, a bay of the Indian Ocean. Many sewers discharge into the river and a lot of litter ends up in it. In practice, the river is a large open sewer. The pollution is so bad that fishermen of Koliwada, the original fishing village in Dharavi, can no longer catch fish in Mahim Creek. If a sewer pipe were installed directly from Dharavi into the ocean, it would be a vast improvement to the environment and fish stocks.


Photo 7. Elevation of an embankment. Building techniques are visible as in a CT-scan section of a body.

The embankment of the river is a sharp boundary of the arable land. So sharp that a view on the neighbourhood looks like an abrupt section. As the application of finishing on the water side is almost impossible, techniques used can be clearly seen on that side of the structures. Various types of stones and bricks are processed into a brick wall. The facades of the street are finished with stucco in various colours. The toilets which have been built really on the edge of the wall, have a perfect drainage. In case of interrupted water supply, the drain remains doing its job.
Life on the edge of the slum means an increased risk, as experienced by animals in herds, swarms and schools when they are on the border of the group. Only if the edge has a physical barrier such as a wall or a moat, the risk of destruction is reduced again.

1. Shelter Associates, Pune India, the Pune Slum Census project , Seventh International Seminar on GIS in developing countries, 15 - 18 May 2002, read 18 october 2009.

Multiple Floors

Adding Up

Adding a floor to your house is the best way to let your home grow. An additional floor and four walls is all you need. And of course stairs to get there. Everything else is already in place, the foundation, the front door and the roof. This roof can be reused by just lifting it a few meters.


Photo 1. Multi family dwelling. Upstairs has an independent entrance.

The staircase is of course the most notable new thing in the house. In this house the staircase landing of the first floor is conveniently doubling as the front porch of the house below. Note that a tarp lies over the clothesline, to protect the washing against the bright sun and down whirling dust. In the dry season dust is blown into Mumbai from India’s interior. Everything eventually gets covered with a brown layer. Not a drop of rain falls in nine months, therefore the blanket of dust is always present. The first rain of the monsoon washes everything clean and brings happy faces. Buildings, streets, plants and trees get their original colour back.

The outside positioning of the stairs has great advantages. If a family consists of several couples, the couples can live in reasonable privacy while the house is family owned.



Photo 2. Shop houses. Front doors are accessible by ladders.

For retailers, it is of course essential to keep the entire ground floor for trade use. An upstairs apartment is the ideal solution. Here a handy combination is made of the canopy and the overhang of the floor. In some houses the entire first floor juts out, in others it is just a balcony. An awning above the store is attractive and practical. Rain and sun are kept outside by it, merchandise can be showcased and it provides a perfect position for a billboard.

Stairs to the floor are all steep. Actually they are ladders. A comprehensive step would take far too much space at the cost of shopping space. To enter the attic through the ladder is not a problem. Getting out is another thing, it requires agility to safely step out of the door on the step ladder. Where the entire upper floor is overhanging the store, serving as a canopy, it is possible to make a better foothold on the ladder. Not a door in the wall but a hatch in the floor. It is a solution with many advantages. First, it is cheaper. A door and frame is both in purchase and in maintenance more expensive than a floor hatch.


Photo 3. Shop houses without front doors.

Besides that, a door is much more sensitive to heavy rain than a closed facade. The hatch is not exposed to rainwater. A daily benefit is that the stairs are more accessible. On descent, support is easily found around the stairwell.


Photo 4. A ladder giving access to the floor through a hatch.

In this chawl the same solution is used. Chawls are homes that are built by the municipal government. They are distinguished by the serial appearance. Only chawls include several homes, sometimes ten, with several families. It is a kind of terraced houses. Identifiable are the continuous facades and the continuous roof. These are only for chawls. Individual buildings in the slum are strict individuals and never show such uniformities.


Photo 5. Chawl with ladder and floor hatch


Photo 6. Chawls are recognizable by the series. In their terrace houses like setting, they distinguish clearly from slum.

Residents of chawls are official tenants from the (semi-) government and bear legal security. The risk of destruction plays no role in their case. Chawls are therefore not considered slum. The chawls are completely surrounded by slums and slum dwellings are sometimes even built against the chawls. These people do not live in a slum but in a chawl in a slum. This is an important difference.


Whereas the steel stairs are so steep that we could better speak of ladders, steps of a more robust design are also found.


Photo 7. This stone staircase can take a beating, is less steep and has an ingenious twist to the left at its top.


Photo 8. By building a floor over an alley, the density in Dharavi surreptitiously increases.


Photo 9. Three houses with three different outcrops of the upper floor.

Three houses with three solutions. Apparently when building the first floor, it was decided to make the facades in one plane. The fitting of the stairs was resolved differently in each house. The facade of the pink house is a little backwards compared to the two yellow houses. The overhang of the floor is therefore the greatest in the pink house and the stairs can be fit finely in, with a hatch in the floor of the first floor. The overhang above the yellow house is too short for the width of the stairs. On the right it is solved by positioning the stairs next to the house instead. Left something really special is made of it. An additional little bay is made above the canopy creating enough space for a stairwell. If there is sufficient headroom at the top of the stairs, remains a question. One thing comes in handy for the people here: India is the home of Yoga. ;-)

The Use of Demolition

The Risk of Destruction as a Blessing in Disguise

In case of destruction of a building, the culprit can always be found among the triplet of nature, rulers and owners.

When earthquakes, hurricanes, fires and floods destroy homes and their environment, this happens irrespective of the residents’ backgrounds. Rich and poor alike fall victim when the natural forces are at work. Nature is not impressed by the thickness of one's wallet. The only thing that affects the chances for victimization is the choice of the site. Land in higher ground is less prone to flooding. In flat land a landslide is less likely to occur than on a steep slope. The probability of a disaster depends on several factors and varies by location. Locations in risk areas are cheaper than in safe areas and slum is therefore often found in low-lying swamp land like Dharavi or on hazardous steep slopes like the favelas in Rio de Janeiro.

Leaders may decide that a building should disappear. Leaders are, in a formal society, the directors of the city. Homeowners are protected by law and can stop demolition of their home, if at least they own formally. An illegally constructed house of illegal residents stands little chance against the will of a formal ruler. This uncertainty is termed risk of destruction by experts and is often used in the field of poverty reduction. People who, for whatever reason, can not be part of the formal economy or not join the formalized society, are together with their difficultly accumulated existence continuously exposed to the risk of destruction.

Where government is weakly organized, other rulers emerge. For example influential businessmen and industrialists, in the worst case the Mafia. Between the two layers of formal power and informal leaders, other levels are found such as corrupt officials. They are the dark field of formal power being tuned by the informal power. Along this path of corruption after all money is being paid by the illegal for the use of land and utilities. In exchange, they become less prone to the risk of destruction. The boundaries between formal and informal, legal and illegal, sublegal and exralegal are very vague. In the chapter "Powertoni" in his book Maximum City1, Suketu Mehta describes inimitable how the play of forces and powers in Mumbai leads to a randomness of demolition operations in the slums.

The third potentially destructive factor to a building is the owner himself. When he decides that substitution is better than change, the fate of the old building is sealed and the demolition hammer brought out. Replacement (demolition and re-start) is economic when the investment in the old building is fully depreciated. This is an important difference between the formal and informal society. The reasoning in terms of investment and depreciation applies only in the formal society. In the formal economy, assurances can be given through property and land administration about the existence of property that may be pledged for loans. By the risk of destruction, the depreciation period does not apply in the informal society. As the bulldozer may be coming tomorrow, a depreciation of 20 years is absurd. A period of one day would be more appropriate. This clearly shows the crippling effect on credit. If no guarantee can be given that a building will be standing long enough to generate money to pay back the loan, the chances of getting a credit are nil. A mortgage with the property as collateral is unthinkable. The risk of destruction in this way limits the ability to make large investments and demolition of awkward buildings possible. Therefore modifying a building is the most common development in the informal economy.

Paradoxically, in a slum the risk of destruction prevents demolition.

1. Suketu Mehta, Maximum City, Bombay Lost and Found (Random House 2004)

The Top End Variety

Not a developing countries' prerogative


Banks of Sumida river Tokyo.

A high-end economy like Japan may not be the first place to look for Economic Weaker Section (EWS) dwellings. Nevertheless, some homeless people can be found in makeshift shelters. There are several stories on the backgrounds of these homeless. A popular one among westerners says these people have become jobless and cannot bear the disgrace under the eyes of their family. Although many people serve in lifelong employment in one company, even when they do not perform satisfactory by any standard, Japan does have a labour market.
Another story deals with finance, of course. There are people in desperate deep debts, think only of the addicts who are one of the family in the Pachinko parlours. Loan agents do not hesitate to hire gangsters to collect debts. Alex Kerr explains.


"Yakuza (organised crime) threatens your family, comes banging on your door at night or calls you in the office twenty five times per day. As a result ten thousands of people disappear every year in a process known as Yonige, ”Midnight Run”. They leave their homes, change identity and move to another city, all to hide from the enforcers of Japan’s consumer loans.
Traditionally people must clear all debts by the end of the year, so New Year’s Eve is the premier time for Yonige. The 80.000 who fled in het night of 1996 had nearly doubled by 1999, to 130.000.
So popular is the Midnight Run that it has spawned a new business, Benriyasan (Mr. Convenient), facilitators who help families flee their
homes and who take care of their possessions while they are on the run. In 1999, Japanese television featured a new drama, “The Midnight Run Shop”, whose hero devises schemes for people to evade gangster lean enforcers. It’s a Mission Impossible for debtors,... "
Alex Kerr, Dogs and Demons, The Fall of Modern Japan, Penguin, 2001, page 270.


Banks of the Ara river in Tokyo.




Moreover, it is clear we are not dealing with muddled people here. The improvised dwellings are neat. They sit on a wooden platform and everything is tidied up. The gray shelter even has an overhead door on a rack. Although this scene is utterly Japanese, there is one feature that definitely refers to the global architecture of dwellings of the displaced: the blue sheet.

In real estate, there are three factors of importance to the value of property: location, location, and location. Therefore most remarkable is the location of the shelters of the homeless in Tokyo.


Photo collage of the Amsterdam Eastern Harbours(left) and Tokyo Sumida River.
In Amsterdam, living on the water is considered highly luxurious whereas in Tokyo the riverbanks are left over for the homeless.


While in many countries living on the water is considered very attractive, the Japanese consider their rivers and the sea as primarily hazardous. Rivers in Tokyo are screened off from the city with high concrete walls. The banks provide excellent space for those who look for a place to put their shelters. Others hide their tent in the bushes and shrubs in public parks.

In debates about homeless people, new groups of displaced people have appeared. Executives on business trip spend fewer nights at home than out. In addition, even ordinary commuters fall victim to this trend. As commuting becomes too time consuming, more and more people sleep in hotels instead of there home bedroom.

From the top, things may look upside down.

Tabula non rasa

Slum is an accumulation of improvements

Building often begins with demolition. A building that does not meet requirements any longer must make room for something new. It is often no use to build on what already was, and the purpose of scrapping is to begin with a clean slate, the tabula rasa. Demolition makes working a lot easier for designers and builders. Designers do not need to study the current situation and do not loose time puzzling on new features in old spaces. It is easier for builders. Tinkering with existing work is very labour intensive and full of uncertainties. It is unclear how sturdy the existing work is and how it is fit together. Many builders prefer to start something new.

The building being demolished was once established through various design choices. The choices made in the past are reversed with the demolition. Demolition is actually a step back in time, a step into the situation prior to the demolished building. With this step back in time history is lost. The new building says nothing about the history of building on that spot. The building history is at best found in a memory.

In a slum, one can often not afford the luxury of demolition. Building a larger home usually means extending an existing house by a floor on top. Choices from the past remain visible and set implications for further development. Continued building means puzzling with the existing situation. The current situation imposes restrictions on the new design. It requires much creativity and inventiveness to get all connections, both spatially and technically, of old and new quite right. Design issues and building projects are therefore in a slum more complex than average. As a result, especially proven techniques are used. Style architecture makes little chance. Avoiding risk is crucial, because of financial constraints. In his book How Buildings Learn1, Stewart Brand shows how not only the initial design determines the shape of a building, but also how the subsequent existence leads to growth and change. In a slum, especially that growth and change are built, not style and originality. “High-style architecture likes to solve old problems in new ways, which is a formula for disaster, according to Dell Upton at the University of California. Vernacular builders, he says, are content to accept well-proven old solutions to old problems. Then they can concentrate all their design ingenuity strictly on new problems, if any. When the standard local roof design works pretty well, and materials and skills are readily available for later repair, why would you mess with that?”2 This risk-evading manner is a basic principle in building slums.

What makes Dharavi so fascinating is the ability to read the entire history of construction on the existing buildings. All the creativity that was necessary to achieve something good under difficult circumstances and all imagination that facilitated further development is visible to those who have an eye for it. Stewart Brand also observes that: "There is a magazine called Progressive Architecture but none called Conservative Architecture. If there were such a magazine (...), it would be largely about vernacular architecture, which is profoundly cautious and imitative, so immersed in its culture and its region that it looks interesting only to outsiders.”3 The architecture of Dharavi and other slums meets exactly this description. Indeed, not only the appearance is cautious and conservative, the physical reality is too. Demolition is a rare activity.

Although an architect will never design a slum, the architecture of a slum is an essential source for designers.

1. Stewart Brand, How Buildings Learn, what happens after they’re built (Penguin Books USA, 1994).
2. Quote in ibidem, p 132.
3. Ibidem, p 132.

What "The Perfect Slum" is about

Using the word Slum in a positive way is uncommon to many of us. Generally it is used to refer to dwellings not meeting the most basic standards of hygiene and quality. Slum is considered hopeless, something to be eradicated. The word is used often to disqualify the residents and expel their position from the debate. Developers use the slum-word as a powerful sound to support their case. The slum-word is so loaded that beneficial people prefer to use 'informal settlement' or 'incremental development'.

It is the intention of the author to look for the positive side of 'slum', and to learn form it. Understanding the way of living of people is not a one way journey. The idea that architects from the so-called 'developed countries' might learn a lot from what happens in the 'developing' countries, may require a U-turn in our thinking. And as lady Margareth Thatcher once said (in a different meaning though): if you are in for a U-turn, you turn!

So please, join us to the world of practical architecture, revealing the logics we no longer value in 'modern' architecture.

No architect would ever design a 'slum' and there is no need to. People are designing and building their own home and have no need for an architect. All choices for what is needed, what is practical, what is beautiful, what works, what is feasible and what is really wise, are made like everyone in the world would do: with common sense. Their way of building is definitely the most sensible way of building there.

As all buildings, informal settlements are a reflection of the circumstances under which those houses are made and used. Climate is a clearly recognizable factor and by the form of the roof, we can recognize in what climate a house is located. Tangible circumstances include available space, available building materials, population density, and climate. Then there are the intangible conditions such as economic perspective, formalities, property, and the balance of powers.
We can find all these circumstances in the way of building. If wisely built there is a logical link between construction and conditions. This relationship has a big advantage when we get somewhere we have never been, as we can see the conditions by means of the construction. Reading the environment is a basic instinct. Wherever in the world we are, we will always make a reconstruction of the circumstances, based on what we see.

If we look with Western eyes at a house of which the roof is made watertight with a blue construction tarp, we conclude that no money is spent on an expensive roof. The money is clearly not available so the economic perspective of the residents is not good. The residents suffer poverty of course. The reconstructed condition poverty results from the Western connection that only poor people live under a rickety roof.
However, perhaps the conclusion poverty is totally wrong. Might it be prudent not to make a strong waterproof roof while not suffering poverty? Yes, in a provisional dwelling this is often very wise. The weather in Mumbai is very reliable. During the monsoon, it rains three months on end. Then the other nine months are dry and this cycle runs since immemorial times. Three quarters of the time and in fixed periods, there is certainly no rain. This security is remarkable, especially if we compare it with the certainty of the existence of an informal dwelling. There is a significant risk that the house will be demolished soon. The house is not legal and it is very wise not to make an expensive roof on an illegal house. A blue tarp for a few months per year is a much wiser investment. The conclusion from the Western perspective that the inhabitants of a ramshackle house with a shoddy roof and a blue tarp live in poverty, is not necessarily correct. Many residents have the money indeed for their home improvement and would love to spend it, but let's face it ...

Would you:
build a house for yourself ... if there is a chance of the bulldozer coming tomorrow?

build a storey to your home ... if there is a chance of the bulldozer coming tomorrow?

together with neighbours, construct a sewer in the street ... if there is a chance of the bulldozer coming tomorrow?

together with neighbours, pave the street ... if there is a chance of the bulldozer coming tomorrow?

The insight of building in a slum being done in a very sensible way and the belief that it is not justified to discard the 'slum' phenomenon as sheer poverty, are the motivations for the exciting project The Perfect Slum.


By letting residents tell about their homes, we will see the circumstances giving rise to surprising priorities in architecture. Based on their story, it is clear that building and living in a hand built shelter is a great achievement.

Connecting to People

A matter of give and take

As a preparation for the Urban Typhoon 2008 workshop on the development of Dharavi, Asia’s largest slum, I travelled to Mumbai one week in advance of our gathering. In order to familiarize with the subject of our workshop I stayed in Dharavi and walked it every day. And I walked it every night. As a method of surveying cities I take pictures of everything that is catching my eye. I had done this in Tokyo one year earlier and it had proven its value to me.

The people of Dharavi are very willing to have a picture taken of themselves and their business. I took many pictures of how they live, work and trade. It gave me insight in how a slum works and how the moods are of the people living there. But it made me feel uncomfortable as well. I was taking pictures without doing anything in return. The insights all these people gave me were so invaluable that finding a returning favour became inevitable. The internet shop opposite Sion station inspired me to an appropriate response for taking pictures, which is: giving pictures. The internet shop offered printing facilities so I printed the portraits of everybody I figured I would be able to track back.


Kunal was of tremendous help, he printed dozens of portrait photos.

Armed with stacks of pictures I went back into the slum of Dharavi, where some 800.000 people live and the streets have no names, looking for people, their business, their family, their shop, their kids. And it worked out very well.. People were very surprised and very pleased to get a picture of themselves in their most daily situation. Everyone I met gave me a feeling of mutual joy. Kids rushing home cheering, waving with the picture. Grown-up men looking for words. Moreover, it opened up the world I was trying to survey. I was invited to join drinking tea in private houses, in the local gym, in what appeared to be a company in sound and lighting systems. I was guided through the narrowest backside alleys, in pitch dark, in order to find that boy in the picture who appeared to be the brother of the friend of the nephew of my friend whom I met for the first time one minute ago. And so on. In the process of delivering the pictures to the right persons I learned more about Dharavi and its people than I imagined possible.


Social structures, economics, ethnics, religious segregations, architecture, urban planning, infrastructure, commerce, business, living, education, tradition, and so on. All I wanted to know came within reach by simply giving pictures.