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 issue 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
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.[1]
A. Coordination of environmental, economic and social requirements
A.1 Environmental. (Kwok and Grondzik, 2007) 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.
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.[2]
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’.”[3]
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.[4]
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.[5]
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.)[6]
“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). [7]
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.
B. Embodiment of approaches
Short term.
Medium term
Long term
C. Issues on built environment
C.1 Housing
C.2 Public Market
C.3 Day Care Center
C.4 Health Center
C.5 Multipurpose Hall
C.6 Schools
C.7 Water
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. The quantity of water affects seasonal allocation, conservation techniques, waste water treatment, population and the like.
C.8 Energy
Each year, over three and a half times the energy needed to satisfy all the power requirements of an energy efficient household falls on the roof of practically every dwelling.
Solar power, with its democratic distribution though out the world, is for the people to consume. The quality and quantity of solar energy is sufficient for human life support in most life zones. The passive solar concept is to allow nature to operate the systems with a minimum of mechanical interference. The potential for heating, cooling, and powering dwellings, factories, and office buildings by non mechanical means exists.
Passive acceptability requires insight into what makes people comfortable. Usually people associate comfort with relative loss or gain of body heat. However, the sense of comforting involves many factors besides temperature alone.
Solar heating systems, whether active or passive, act in much the same way. The sun’s heat is gathered by solar collectors of the structure, transmitted to the heat storage mass, held until needed, and then distributed to the spaces for warmth.
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.
A building that passively utilizes the energy of the sun for year- round space conditioning involves three basic principles:
-it must be designed to accept or reject solar heat when called for
-it must have the thermal integrity to maintain internal comfort despite the range of climatic forces acting on its weather skin
It must incorporate the ability to retain the presence or absence of heat within. With passive solar design the approach is different. Conventional heating is relegated to the status of back up or auxiliary. The first concern is to design a structure that minimizes heat loss to the outside and eliminates wasted heat loss. After the natural potential has been optimized, back up heating of active solar storage, wood stoves or conventional heating can be sized for full tilt.
The way in which a building intrudes upon the landscape and atmosphere will determine its thermal integrity. Each structure presents a profile to the world and the weather. Generally, the simpler the profile, the less its exposure. A well insulated building with excessive profile can lose more heat per volume than a poorly insulated structure with a simple profile.
Profile is a combination of style, logic, structure, ego, function, and volume. Each building that is to have thermal integrity should reflect the climatic forces working n the land where it is sited. If a building is well designed, its profile will blen with the landscape and accommodate the weather.
Minimizing heat loss is one reason, and an important one, for simplifying exterior form. Minimum exposure to north side where the sun never shines, burrowing into the surface of the earth to reduce outside surface area, orienting away from strong, and clustering structures—all of these help reduce heat loss and satisfy an intuitive, yet often neglected, need for graceful repose on the land.
Shading. Shading the exterior, interior, and surrounding areas of a structure is the first line of action to reduce the temperature build- up due to ambient air and solar incidence. By limiting the amount of heat buildup in the thermal mass of a building, the job of cooling is reduced.
Planting of trees. The planting of trees, bushes, or vines in appropriate places can adequately shade structures in many climates. When attempting to cut solar gain into a building, it is important to interrupt the sun’s energy before it strikes the glass or walls. Once the heat has penetrated the envelope of a structure, it must be removed from the interior which may require additional unnecessary steps.
Evergreens planted to the north of the buildings act as buffers. Further, they act as evaporative coolers, lowering the temperature of air passing through branches and needles. They also shade the ground around the buildings, preventing heat buildup in the earth thus modifying the microclimate.
Low shrubs, bushes, and grasses are advantageously planted around building where a view is desired. They reduce reflection of solar energy form roadways, walks, patios, sand, or bodies of water. These shrubs, when watered in the morning, will cool air passing by, evaporatively cooling the area around a structure and reducing secondary heating effects.
C.9 Transport
C.10 Wastes
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).[8]
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.[9]
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.
Berger (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.[10]
Moisture- regulating materials.
Temperature- regulating materials.
Nose- regulating materials.
[3] Oliver, Paul. (2006). Built to meet needs: Cultural Issues in Vernacular Architecture. Burlington: Elsevier Ltd.
[5] Yudelson, Jerry. (2006). Marketing Green Buildings: guide for engineering, construction and architecture. London: Fairmont Press.
[6] Day, Christopher. (2002). Spirit and Place: Healing our Environment, Healing Environment. Burlington: Architectural Press.
[7] Day, Christopher & Parnell, Rosie. (2003). Consensus Design: Socially inclusive process. Burlington: Elsevier Ltd.
[9] Wright, David. (2008). The Passive Solar Primer: sustainable architecture. Atglenn, Penn: Schiffer Publication
[10] Berge, Bjorn. (2001). The Ecology of Building Materials. Oxford: Professional Publishing Ltd.
No comments:
Post a Comment