CHAPTER 2
REVIEW OF RELATED LITERATURE



Literature review will provide the research strategies to different aspects of housing provision, its importance and effectiveness. The following concerns are:

a. Coordination of environmental, economic, and social requirements
b. Embodiment of approaches to issues which can operate over time scales set at short, medium and long term; and formulation of range of overall objectives linking different scales of development and influences
c. Issues on built environment; energy, transport, water and wastes are addresses in a coherent manner to avoid conflicts
d. Technology and Materials
e. Bio- climatic Architecture
f. Case Study
f.1 Local
f.2 Foreign

According to Sieverts (2003), the whole building design and procurement process is very complex and encompasses development and construction from the urban and regional scale down to that of the individual dwelling. The involvement of local communities in formulating a criteria against which development is judged, and in approval access can be fragmented at the present time and this means that single emotive issues can sometimes dominate to the exclusion of an overall understanding.

A. Coordination of environmental, economic and social requirements

A.1Environmental. The process of design, particularly in early schematic stages is by necessity transformed by and ecological focus. Working with environmental strategies is more than assembling parts, or the choosing of systems as if selecting from a menu. Like a great collage, it is important for the parts to blend. (Kwok & Grondzik, 2007)

According to Viljoen and Bohn (2001), the choice of building materials affects the environmental impact of a house. All building materials are processed in some way before they can be incorporated into a building. The processing may be minimal, as in the case of a traditional cottage constructed from materials found locally, or it may be extensive, as in the case of prefabricated construction. This processing of materials inevitably requires the use of energy and results in waste generation.

Oliver (2006) quoted, “I will endeavor to enlarge on these misgivings, but first we should ascertain what is meant by these words. For guidance I turn to those standard works the Oxford English Dictionary and Webster’s Dictionary. In these, we find that the verb ‘to environ’ means to ‘encircle’ or ‘surround’, and the ‘environment’ is that which surrounds an object or living thing: ‘whatever encompasses’. Biologically, it is ‘the aggregate of all external and internal (my emphasis) conditions, affecting the existence, growth, and welfare of organisms’. It can be argued that there is no entity that is ‘the environment’, but an infinite variety of environments for all physical phenomena. Similarly, we may discover that ‘behaviour’, while meaning for some 500 years, ‘conduct or course of action towards or to others’ has also meant for nearly as long a time, the ‘handling, or disposition of anything’, such as the ‘manner or action of a machine, a chemical, substance, organ, organism, etc’.”

These gave an indication of the direction to which he would turn, as he argued that an understanding of behavior patterns is ‘essential to the understanding of built form’ and that ‘forms, once built, affect behavior and the way of life’. In his view the forms of vernacular buildings result from ‘the aims and desires of the unified group for an ideal environment’ and socio- cultural forces ‘become of prime importance in relating man’s way of life to the environment’. Whether the ‘ideal environment’ is indeed, an objective or, in many cultures, is even a concept, remains to be demonstrated.

A.2 Economic. Ensuring that the housing solutions of the informal settlers are sustainable is important. On the part of the re- settlers, sustainability means that their new homes must be affordable, income adequate is maintained, and access to essential services like transport, education and health care is adequate. For the government, sustainability means, to the extent possible, costs are recovered. The government has to get back its initial investment so that it can then make use of these resources to build more homes for other informal settlers.

The value of buildings depends on the nature of ownership. For example, a major government agency may construct buildings with a 50- year (or more) life, whereas a property developer may simply construct buildings for immediate leasing and short-term sales potential. Each of these building owners is pursuing different measures of value, and the task for green building marketers is to recognize this state of affairs and to tailor their approaches to different owners accordingly.

According to Yudelson (2006.), buildings also build up value by having lower operating costs. In a low interest rate climate, the multiplier of annual savings to get incremental increases in building value may be as high as 14 (cap rate of 7%), whereas in higher interest rate environments, it can shrink to 10 (cap rate of 10%). So, the same projected annual savings in energy and water costs, or benefits of productivity increases, might be worth 40% more in a low-interest-rate economy.

A.3 Social. Cities are predominantly shaped by thoughts, however uncoordinated. Landscapes, by contrast are shaped by elemental forces. In principle, warmth and plants drive upward, water and matter transport downward. Vegetated landscapes tend toward balance. Towns don’t. almost all manifest excessive dryness. Dryness is a soul quality—arid, harsh inflexible and dead. In urban projects, it is encouraged to mitigate this using trees and ground plant in buildings. (Day, 2003.)

“It’s a sad fact that many people live in places that they don’t feel connected to. They don’t feel their value confirmed by the places where they live and consequently don’t themselves value these places. Such places attract abuse – starting with litter, then progressing via graffiti to vandalism and worse. They silently abuse the people who live in and use them. These are places over which residents have no control – or at least perceive themselves powerless to do anything about. Lea View House in Hackney, London is one example. Prior to rehabilitation in the 1980s, 90% of the residents of this public sector housing estate wanted to leave. Following intensive architect–resident collaboration, this socially and physically deprived community was turned into a place with positive community spirit. Vandalism, thefts and muggings, formerly common, virtually disappeared; tenants’ health improved, communal areas were looked-after and dignity and respect re-established. People now wanted to move onto the estate.” (Day and Parnell, 2003). This is just one illustration of the way care flourishes once a community feels proprietary about a place. As well as improving physical environment, this encourages social bonding, crime reduction and shared responsibility. However ugly, polluted, environmentally abused, is a place, the relationship to it changes as soon as people free to alter it. And it changes profoundly once people start work on it. It becomes their place – something they value. Not only are they empowered to co-shape our own future, but what people value, think, feel and do counts. It is of significant consequence – and so, therefore, they themselves.

People’s response to housing resettlement is characterized by patterns of coping strategies evident in how they generally deal with the compound conditions of poverty. The uncertainties that the urban poor face force them to “improvise” in order to survive in a fast-changing world that is increasingly making their lives more difficult. Because of limited resources and the various conditions that shroud their capacity to take hold of their future, the urban poor come up with short-term, quick- fix solutions to each problem as it arises. These coping strategies become part of the people’s culture and turn into a stock of knowledge which supplies people with interpretations and guides of action as they confront opportunities and challenges in their lives.

B. Embodiment of approaches
Short term.
Medium term
Long term

C. Issues on built environment

C.1 Energy
According to Grondzik & Kwok (2007), consideration of on- site energy production should begin with a review of energy efficiency strategies. Every effort should first be made to reduce demand. Reducing demand reduces the size of an on- site generation system or permits a system of a given size to offset a greater percentage of building energy load.
Given an efficient building, on- site energy production can further reduce environmental impact. Selecting the best strategy for on- site generation will depend upon factors such as type and location of the project, regional and micro climates, utility, rates and possible tax and financial incentives for clean and/or renewable energy.

“Plug loads have little direct effect on the architectural design of a building—electrical wiring is easily coordinated and concealed. The energy demands resulting from plug loads, however, will affect building energy efficiency and consumption, the sizing of cooling systems, and the sizing of on- site power generation systems. The greater the plug loads, the larger the supporting electrical system must be.”, says Grondzik & Kwok (2007). The design of on- site power and passive and active cooling systems demands that the nature of plug loads be well estimated during schematic design. The direction of design should be toward green (energy- efficient) plug loads

Solar Energy

Principles
The principle of power generation is in all cases the same: Heat energy from combustion of fossil fuels or from nuclear fission is used to drive a thermal engine—in most cases using stream turbines—and to produce electric current via generators coupled to the turbines. Solar thermal power plants use exactly the same technology, which has been refined for more than a hundred years. They simply replace the conventional heat sources by solar energy.

Solar thermal power plants work in principle like a magnifying glass. They concentrate the rays of sun , in order to obtain high temperature. The required working temperature necessitates strong, direct solar radiation, and this determines which locations are appropriate for solar thermal power plants. They can therefore be operated economically only within the—enormous—sun belt between the 35th northern and 35th southern latitudes.

The concentration of light
Wengenmeyr (2008) quoted, “Nevertheless we can in this way theoretically arrive at about the same radiation energy density on the surface of the Sun, and could in principle obtain heat at a temperature of several thousand Kelvins”. An alternative is offered by linear concentrators, for example cylindrical lenses: They do not concentrate the radiation at a single point, but rather along a caustic line, so that they need to e moved around only on axis in order to follow the sun.

C.2 Water
Access to good quality potable water is fundamental to human survival and therefore basic to any slum upgrading scheme. The human right to water has been recognised in various international standards, in particular the General Comment No. 15 on the Right to Water which states that: “The human right to water entitles everyone to sufficient, safe, acceptable, physically accessible and affordable water for personal and domestic uses.”

In many low-income settlements, water is both scarce and expensive. In some countries slum-dwellers pay up to 30 times more than middle class residents for their water. Moreover, inadequate sanitation is one of the main sources of water contamination in urban poor settlements, leading to diseases and millions of deaths each year. Providing adequate sanitation facilities is therefore equally fundamental to low-income settlement upgrading.

The location of water in relation to the surface of land is a determining factor in type of water supply, building location, surface drainage, vegetation, and so on (Serote, 2004). The quantity of water affects seasonal allocation, conservation techniques, waste water treatment, population and the like.

According to Metcalf and Eddy (2006), “…for many water reuse applications such as agricultural irrigation and industrial cooling water, effluent from secondary waste water treatment plants was historically of sufficient quality. However, as quality goals for these and other water reuse applications have increased, spurred by the adoption of water reuse regulations, additional treatment has become necessary. Meanwhile, as regulations for effluent disposal have become more stringent, additional treatment has become necessary even for plants not practicing reuse. Thus, were feasible, it is reasonable to consider designing a treatment system suitable for potential future water use applications” the technologies now used for water reclamation have evolved from operation and processes used for water and wastewater treatment. Even greater removals for measurable constituents are possible through recent technology advances.

Treatment technologies for water reclamation applications

Because of the importance of water quality in waste water treatment and water reuse applications, different technologies are utilized, either singly or in combination, to achieve desired levels of constituent removal.

Centralized treatment Plants. In a typical centralized plant, the treatment plant is located at a low point in drainage area, usually near the point in the drainage area usually near the point of effluent disposal. At the time of selecting the original location of the treatment plant, the area surrounding the plant may have been relatively uninhabited. Overtime, however, the surrounding land may be developing to any use. In this environment, some local water reuse opportunities might be available such as landscape irrigation and supplying industries with processed water.

Table C.1.1 According to Metcalf & Eddy (2006), there are advantages and disadvantages for the centralized treatment facility:

Advantages Disadvantages
Satellite Treatment Facilities
*Opportunities for finding sites for local reuse of reclaimed water are enhanced * Site selection might be controversial for treatment plant and storage locations in or near residential areas due to zoning, local and land use ordinances, and public opposition
* The supporting infrastructure and its cost can be reduced significantly as compared to the centralized system * Availability of wastewater supply in the collection system may not correlate with water reuse demand
* Greater potential for having reuse applications adjacent to treatment system, thus minimizing transmission costs *Requires additional monitoring equipment and telemetry for operation and control
* Availability of land in the upper reaches of the service area may be better for locating satellite treatment and storage facilities * Labor and monitoring requirements will be more costly with the addition of facilities in remote locations
* Diversion of untreated wastewater from the collection system reduces the hydraulic load on the collection system and central treatment * May be more difficult to ensure reliability of water reclamation system and power supply
* The overall cost of a distributive treatment system may be more cost effective than an expanded centralized system * If the chemicals are required for disinfection and other purposes, transport of hazardous materials through non industrial areas may be required
* Energy consumption may be reduced by eliminating long distance and high pressure reclaimed water transport * If membrane bio reactors are used, special chemicals and equipment may be required for membrane cleaning and replacement
* Construction disruptions may be less, especially for pipelines in public streets * Discharge of biosolids back to the collection system may lead to the information of odors


C.3 Transport

For housing to be satisfactory it must be situated so as to allow access to employment opportunities, health care services, schools, childcare centers and other social facilities. It must also be located in an acceptable environment, not, as is often the case, in environmentally hazardous areas such as dump sites, steep slopes, or flood prone areas. Though low-income settlements usually lack public facilities, it has been recognized that strong social networks play an immensely important role in alleviating this de.cit as well as in creating employment opportunities. Slum upgrading, as opposed to relocation, should make sure that social networks are maintained and distances to the work place are kept reasonable.

C.4 Wastes

All waste system elements should be looked upon as being stages in the movement, or flow, of materials from the mining stage, via processing, production and consumption stage towards final treatment and disposal. A waste management system is a combination of several stages in the management of the flow of materials within the city and the region. A waste management plan is part of an integrated materials management strategy, in which the city makes deliberate and normative decisions about how materials should flow. The waste elements then become specific tactics to deal with specific materials after they have been consumed.

According to Klundert & Anshutz (2001), “Hazardous waste should be a particular area of concern during assessments of waste management systems. Hazardous waste is waste that is potentially dangerous to living beings and/or the environment. Hazardous waste is produced by a variety of sources including households, large- and small-scale industries, healthcare establishments, commercial operations like vehicle servicing, airports and dry cleaning shops and agriculture (e.g. unused pesticides, herbicides).” It is necessary to know what type of hazardous waste is produced by which sources in what quantities in the community. There are also numerous small enterprises that store their hazardous waste with the ordinary household waste, so it is mixed collected and disposed.

Instead of copying high- tech waste collection systems from abroad, it is encouraged to: (1) Allow a mix of approaches and technologies to be included in a well planned overall collection system, which includes sufficient secondary collection and transfer points, adequate shortage space and drop off centers; (2) Enabling specifically allowing pluralistic approaches in laws, ordinances, and regulations, and encouraging pluralism in private sector contracts; (3) Selecting a combination of collection techniques that allow for optimum recovery of valuable materials by municipal and private collectors (Klundert and Anshutz, 2001).



D. Technology and Materials

The earth’s resources are usually defined as being ‘renewable’ or ‘non-renewable’. The renewable resources are those that can be renewed or harvested regularly, such as timber for construction or linseed for linseed oil. These resources are renewable as long as the right conditions for production are maintained. Thinning out of the ozone layer is an example of how conditions for the majority of renewable resources can be drastically changed. All renewable resources have photosynthesis in common. It has been estimated that man uses 40 per cent of the earth’s photosynthetic activity (Brown, 1990).

The use of materials reflects another facet of the passive attitude. It takes over three hundred times more commercial energy to produce a concrete block equal in volume to a sun dried adobe block. It is conceivable to create a structure of integral thermal storage mass with an adaptable transmittive/ insulative weather skin that will accept or reject and automatically store all externally indecent heat energy or internally generated energy.

According to Berge (2001), a building structure usually consists of the following parts:

• The foundation, which is the part of the building that transfers the weight of the building and other loads to the ground, usually below ground level. In swamps and other areas with no load-bearing capacity the load must be spread onto piles going down to a solid base.
• The wall structure, which carries the floor, roof and wind loads. The walls can be replaced by free-standing columns.
• The floor structure, which carries the weight of the people in the building and other loads such as furniture and machinery.
• The roof structure, which bears the weight of the roof covering and possible snow loads.

Structural materials have to fulfill many conditions. They are partly dependent upon the construction technique to be used, and their properties are defined in terms of bending strength, compressive strength, tensile strength and elasticity. These factors give an idea of the ability of the material to cope with different forces. How this happens depends upon the design and dimension of the structure.

Berge (2001). Climate regulating materials control the indoor climate, and are mainly orientated towards comfort. They can be subdivided into four groups:
• air-regulating
• moisture-regulating
• temperature-regulating
• noise-regulating.

Air- regulating materials. Wind-proofing a building takes place in two areas, topographical and other wind breaking effects in the surroundings, and a wind-proofing membrane forming part of the building’s outer skin.

Moisture- regulating materials. Moisture-regulating materials are primarily used for waterproofing foundations, and as an inner vapor barrier to stop moisture from inside the building penetrating the wall and damaging it. They include materials that can regulate and stabilize air moisture in permanent absorption and emission cycles.

Temperature- regulating materials. Temperature-regulating materials mainly include thermal insulation materials built into the outside surface, but also materials that stabilize temperature relationships through their warmth-regulating properties. Subgroups for internal use are surface materials that can reflect, absorb or carry heat radiation through their structure and color.

Noise- regulating materials. Noise regulation is necessary to reduce and transfer sound of different qualities in and between rooms, and to guarantee a good acoustic climate. External sources of noise, such as road and air transport, necessitate good insulation in both walls and roof. Noise-regulating properties are dependent upon the material used, its design, placement and size.


E. Bio- climatic Architecture
Bioclimatic buildings are characterized by the use of building elements including walls, windows, roofs and floors to collect, store and distribute solar thermal energy and prevent overheating. Heat flows occur primarily by the natural mechanisms of convection, conduction and radiation rather than through the use of pumps ad fans. The objective is to manage energy flows and thus provide comfortable conditions in the occupied parts of the building at all times of the year and day. The definition also includes natural cooling and shading. The building is cooled by rejecting unwanted heat to ambient eat sinks (air, sky, earth and water) by means of natural modes of heat transfer. But the cooling load is firstly minimized through architectural design by reducing solar gains to the building fabric or through its widows, and by reducing internal gains. Thirdly, the use of radiant energy for daylighting while maintaining standards of visual comfort is also encompasses within the bioclimatic approach.

Integrated Design Principles

The main principle of bioclimatic design for passive and low energy buildings is to provide a comfortable environment by virtue of the passive features of design. A second principle is to use the active systems (mechanical equipment, such as air conditioning) with the passive systems to create an integrated solution for climate control. This can produce an integrated approach to design. This climate control concept requires a cross-disciplinary design method involving both architect and engineer to achieve an integrated solution. One view of bioclimatic design is that the sphere of influence of architectural design lies in the use of passive design features, such as selecting the appropriate form and fabric of the building for climatic conditions. The aim is to achieve the indoor condition as close as possible to the comfort zone. Hence, through building form and fabric, varying outdoor conditions are controlled in order to achieve comfort. There are limits to the effect of passive systems; hence it is common to use active systems for times when comfort cannot be provided by passive systems.


































ENDNOTES