RESEARCH
PROPOSAL
ON
BUILDING
MATERIALS IN SOUTH- WESTERN NIGERIA.
(AFFORDABILITY IN BUILDING CONSTRUCTION THROUGH THE USE OF
INTERLOCKING BRICKS)
BY
The Other
Woman In Marriage
Reg. No. /03/1893
DEPARTMENT OF BUSINESS ADMINISTRATION,
UNIVERSITY OF ABUJA.
June , 2015
Housing:
permanent shelter for human habitation. Because shelter is necessary to
everyone, the problem of providing adequate housing has long been a concern,
not only of individuals but of governments as well. Thus, the history of
housing is inseparable from the social, economic, and political development of
humankind. From the beginning of civilization, attention has been paid to the
form, placement, and provision of human habitation. Rawar, R.S. (2000).
At present,
there is both a demand for housing and a supply of reusable structures that are
going unclaimed. This situation is a good example of the complex role housing
plays in society. Its primary function is to serve the need for shelter and
privacy.
Earth
architecture has a longstanding tradition in the south-western part of Nigeria.
According to the various techniques and materials, we differentiate between
layered, rammed, wood-framed, adobe and wattled earth-walls.
By the
1960's, earth architecture was entirely substituted with brick construction.
But starting from the 1970's and 1980's, building with earth has become popular
again. A lot of houses have been refurbished, instead of being totally
destroyed, and with the assistance of the organic architecture, and other
representatives of environmentalism, have started to build new earth houses.
Lenin, O.O. (1999).
Interlocking
bricks have always been in use to a lesser extent, but extensive studies on
this technology only appeared after the first ecological-villages came into
being. Few of these buildings are in south-western Nigeria, but there have been
several other experiments in different parts of the country. The construction
of interlocking bricks structures is limited though, since builders pick this
particular material mostly for ecological reasons. This special demand normally
comes from only a small group of environmentalists, ecologists or people with a
keen sense of environmental protection, so the use of interlocking bricks has
not become widespread among ordinary builders.
PROBLEM STATEMENT
The major problem to be solved is the ignorance of the people
towards the advantageous use of interlocking bricks in building construction in
the south western part of Nigeria. A very great observation is that developers
have neglected the use of traditional building materials, most especially
interlocking bricks which have been in existence long ago and have accepted to
a fault, the influx of foreign materials and techniques. This has so much
contributed negatively to the economy of the nation at large. Indigenous/local
materials for the production of these bricks are lying waste and
unextracted. This has raised the cost of
acquisition of building by both private and public sectors. This calls for an
urgent re-orientation of prospective house owners and builders in the south
western part of Nigeria and beyond to consider the use of interlocking bricks for
better quality housing of its population at a relatively lower cost/rate.
AIM AND OBJECTIVES
The study of interlocking bricks and its mode
of construction in this context aim at its use as a walling material. Bricks
that has been in use since the Neolithic period of man’s existence is presently
discovered as being neglected, largely because of the introduction of new
materials and their various methods of installation. The interlocking brick
as a walling material has some distinct characteristics which make it have an
edge over the other walling material. These are exhibited in its relative
cheapness, availability, low cost of construction, low cost of maintenance. Others
are its simple method of construction, aesthetics and its thermal insulation at
extreme weather conditions etc. All the above mentioned attributes of interlocking brick
wall be expanciated and highlighted in the course of this study to expose the
residents, developers and urban dwellers to the enormous benefits accruing to interlocking
bricks. The aim of this research is to enlighten people of the
south-western Nigeria on providing better quality housing at a relatively lower cost/rate with the
use of interlocking bricks.
The objectives of this study are the proposed ways and strategies
by which the aim of the study can easily be achieved. These include
(a) The in-depth
study of interlocking bricks
(b) Production
process of Interlocking bricks
(c) Exploration of
existing interlocking brick buildings in south west Nigeria.
(d) Cost comparison
between interlocking bricks walls and walls of other materials.
(e) Aesthetical
analysis and the justification for its use in public building.
RESEARCH HYPOTHESIS
·
There is no significant relationship
in the production process of interlocking bricks and sandcrete block.
·
The use of interlocking bricks to
achieve aesthetic and form has a significant effect of the building.
·
There is no significant
relationship in the cost of interlocking bricks and sandcrete block.
SCOPE OF STUDY
The knowledge of the use of interlocking bricks in Nigerian
housing is increasingly going far and wide over the years. It is not unknown to
builders, especially those that are solely after cost reduction. Since Nigeria
is regionally divided into various climatic zones which is a significant
consideration in the selection of materials for wall. For the purpose of this research,
the study is shall be limited to the south-western Nigeria. This region
connotes the relatively humid region of Nigeria. The culture, climate, soil
properties and types shall elaborated to make us see the need to go back to
some of the traditional architecture with the intention of improving them
technologically and to make materials of such be able to compete with the
imported materials when it comes to quality.
LITERATURE REVIEW
The research activities that ultimately led to the development of
the interlocking block technique, which is gaining popularity in Thailand, as
well as Malaysia and the Philippines, date back to the 1960s. In these
countries, houses in the rural areas were traditionally built of timber, which
was readily available in the extensive forest areas. However, the alarming rate
of deforestation in Thailand - from 70% forest cover in 1936 to about 55% in
1961 (now it is less than 30%) - led the government to initiate research into
alternative materials for building construction in the rural areas.
Initially, research undertaken by the Thailand Institute of
Scientific and Technological Research (TISTR), Bangkok, focused on soil-cement
blocks made with the CINVA-Ram manual block press (which was developed in Colombia
in 1956). The demonstration houses built with these blocks were cheaper than
timber houses, more durable, resistant to water, fire and termites, and
aesthetically appealing. The disadvantages, however, were that the blocks were
relatively heavy, and building construction required a certain amount of
masonry skills. Furthermore, the mortar joints consumed a considerable amount
of cement and construction time was relatively long. (Steve 98)
BRICKMAKING LATERITE
The type and quality of laterite soil used for brick making vary
since there is no standard criterion which can be applied when determining the
suitability of any laterite deposit for brick production. It was found out that
the earliest known bricks were not fired but were a mixture of clay and sand
reinforced with straw. The straw which was added during the making process
would have a similar effect to that of a fiberglass in glass reinforced
plastics today. Naturally, unfired laterite bricks even when reinforced in this
way, will not last very long in a climate with periods of heavy rainfall as we
have in south western part of Nigeria.
TYPES OF BRICKS
The various available types of bricks may be classified by colour,
mechanical strength and the purpose for which they are intended according to Hamilton,
(1978).
Common Bricks: Used in
building where their appearance is of little or no consequence. It may vary in
colour from red to pale yellow. They are not vitrified and normally not fired
higher than 18300F (10000C). They are not expected to
have a great compressive strength.
Facing Bricks: These are
more carefully made and the quality of the raw materials is vigorously
controlled. They are sometimes fired beyond 10000C to produce a more
acceptable surface and this is accompanied by greater mechanical strength. They
are mostly used on approach elevations, entrance porches and specific areas to
captivate the attention of the observer.
Engineering Bricks: These are strong type of bricks which are fired to the point of
vitrification or a temperature approaching this state under reduction condition
which achieves maximum strength without deformation. Such bricks have very
great compressive strength and the production is carefully controlled.
INTERLOCKING BRICKS
This is an improvement on the traditional adobe bricks that were
prevalent in the 20th century in some African countries. It is a
non-hollowed laterite brick stabilised with cement in the ratio 1:19. It
involves the use of the “hydraform” machine which was invented by NBBRI in
2002. An interlocking building block system comprises a plurality of
rectangular building blocks, each with longitudinal side surfaces, upper and
lower longitudinal faces, and vertical end walls normal side surfaces and
longitudinal faces. The upper longitudinal face of the blocks has a central
longitudinal accurate rib and a pair of transverse spaced accurate ribs
thereon. The transverse ribs extend laterally from the longitudinal rib to the
one of the side surfaces. Corresponding longitudinal and lateral transverse
concave and accurate recesses in the lower longitudinal face mate with the ribs
of an adjacent block when assembled. A pair of spaced vertical slots extends
through the block inwardly of each end wall opposite to the transverse ribs and
terminates tangentially to the longitudinal rib. One block may be placed on the
intersection between of two abutting blocks with one transverse rib from each
lower block received in each transverse recess of the upper block and one
vertical slot from each lower block in vertical alignment with the slots of the
upper block. Corner blocks have a single vertical slot and a third transverse
rib and recess opposite and coextensive with one of the pair of transverse ribs
and recesses formed on the longitudinal faces.
The introduction of modular interlocking bricks in the building
industry not only provides a dimensional basis for the coordination of
dimensions and of those building incorporating them, but it also acts as a tool
towards rationalization and industrialization of the building industry. Modular
building design and construction were born of the need for flexibility,
economy, and adaptability. The proposed interlocking blocks can offer several
advantages such as design flexibility, cost effectiveness, reduced construction
time, environmentally friendly and a solution to space shortage. On the
environmental end, the use of entirely non-hazardous waste material for such
blocks to achieve the above results from locally abundant, readily available
indigenous materials with low embodied energy counts. Because of the excellent
properties in terms of appearance durability and cost, laterite has been chosen
as main material for the project. The object of this research is to investigate
the properties of the various materials.
CHARACTERISTICS OF INTERLOCKING
BRICKS
Interlocking bricks have so many characteristic features and attributes which aids
its identification for use in building construction. Such characteristics are
discussed below.
APPEARANCE
Interlocking bricks are the perfect staple for any building. They
fit together beautifully, are easy to maintain, and give the building a
stunning touch. They can be found them in a variety of buildings from the most
modest to lavish estates. Interlocking
bricks is a type of earth material with a distinct reddish brown colour.
The colour is due to the presence of large amount of laterite. Interlocking bricks could also come in
THERMAL PERFORMANCE
There was an investigation of the thermal performance of reinforced
concrete, interlocking laterite brick building
and sandcrete block building in Port Harcourt carried out by Nyenke and Opara,
during dry and wet seasons reported by the National Association of Certified
Engineers Journals. It was observed that the building with interlocking laterite brick has the
best thermal performance than the others which require mechanical ventilation
or cooling in order to maintain the minimum thermal comfort level within the
building. Enchore, I.J., (2003). The high cost of building and construction
materials in Nigerian has been linked to the high import dependence of these
materials duet poor quality of the locally produced materials, Opara, (1998).
Also the high cost of energy consumption in buildings has reached an alarming
rate. Interlocking brick
buildings generally, are appropriate for different climates and suite solar
heating and cooling. If well designed, they stay warm in the cold seasons and
cool in dry season with little or need for auxiliary mechanical energy. About
half of energy sector is consumed in building space cooling the urban and
semi–urban areas of Nigeria. The space cooling is caused by losses or gains due
to heat transfer by air movement due to infiltration and \or controlled ventilation.
FIRE AND WATER RESISTANCE
When interlocking brick
is buildings, it gives a significant level of fire resistance. The fact that it
had spent a period of at least 36 hours in the kiln during firing is evidence
that it can withstand fire for a long time while it is being strengthened
further. Burnt pulp and saw dust create small holes inside the bricks, which
increase the heat insulation. During grinding, bricks of high margin plain are
produced; this increases the smoothness of the surfaces and thus, appears
coated against easy penetration at a relatively low rate.
AVAILABILITY
To the lay man, laterite means earth or any type of soil but in
the sense of it, the analogy simply demonstrates the ready availability and
abundance of laterite. It is found almost every where in south western Nigeria,
but more commonly found in the savannah, where there is very little amount of
rainfall throughout the year. The type available down south is darker than that
of the savannah but also very good in building construction. Study shows that
the abundance is relatively moderate in south western Nigeria and even much
more than can be fully exploited for use in interlocking bricks by the south
western dwellers of Nigeria when it comes to its use in building construction.
COST
Since the raw
materials for the interlocking bricks are very much readily available in our
immediate environment, it is very cheap and requires little skill in
manufacture.
Where the
same size of interlocking bricks and sandcrete blocks are compared, it was
discovered from the immediate market survey, that the sandcrete blocks cost
more and need to be plastered while interlocking bricks may be left unplastered
to showcase the different aesthetic colours.
AESTHETICS
No doubt, interlocking bricks when used in building are very
aesthetically sound and very pleasing to the sight. In most cases there is no
need for plastering. They are extremely beautiful if well arranged, it also
gives some predetermined shapes and patterns after installation. They
interlocking bricks could also be given different pigmentation to show various
glowing colours.
PRODUCTION PROCESS OF INTERLOCKING
BRICKS
The raw materials for the production of interlocking bricks need
to go through some pre-determined processes before emerging as being
structurally capable of carrying load. These processes are:
·
Soil Preparation
This involves the sieving of the dry soil which is either done
manually or with the use of constructed wire mesh sieve. Some machines are also
available for this type operation in case of large scale production.
·
Mixing
Here, proportional quantities of the materials required are
measured and mixed together. The measurement is achieved by weight or by
volume. Cement of about 4-5% could also be added to further the product. The
mixing is done manually by using shovel and head pan while the large scale
production requires the use of mechanical mixer. At this stage water is added
proportionally. The maximum quantity of water to be added is determined by “Ball Test”
·
Ball Test
The test confirms the plasticity of the soil sample being used for
block production. It is done by shaping a little sample into a ball and
allowing it to fall from a height of about 1.5m. If the ball scatters, then it
is too dry to be used. If the ball breaks into 4 or 5 pieces, then it is
suitable but a ball sample that flattens on landing is rather too wet.
·
Compression
Compressing a soil sample means the application of internal
strength to the material to make it stronger. This is done with the use of
hydraulic machine.
·
Stacking
After compression, the resulting bricks are stacked in the open to
gain some freshness shortly before installation.
·
Curing
This is the stage whereby the product is meant to gain maximum
strength by stacking under 100% humidity for about seven (7) days. The
interlocking bricks are covered with fabric materials to reduce rapid loss of
water. Water is also sprinkled on the interlocking bricks to maintain good
moisture contents of the bricks. It should be noted that after curing the
bricks are ready to be stacked (installed as walls).
ADVANTAGES OF THE INTERLOCKING
BRICK SYSTEM
Some
major advantages of this system are:
1
The system is very aesthetic and
gives more interlocked effects from key and slots.
2
The
construction procedure is simple. It does not require temporary formworks or
propping. Therefore, it can be
erected quickly by unskilled labour, hence saving cost of installation.
3
Less
wastage of materials is involved. There is no
cutting of bricks required during construction.
4
Construction
site cleaner in contrast to traditional methods of construction.
5
Renovation
work of interlocking bricks is much easier to handle.
6
Construction
is faster, thus the waiting time for occupancy of a building is reduced is
reduced to the minimal.
RESEARCH METHODOLOGY
For the purpose of this research work, the method of data
collection and its subsequent analysis, a research methodology will be adopted.
This section presents the methodology that will be used in this research work.
It will comprises the study area (target population), methods of data
collection and analysis and model formulation. Okoko, E. E. (2002), referred to
research methodology as a tool that serves as scaffolding for the validation,
proper analysis and interpretation of data towards guiding a researcher for the
realization of the set goal and objectives. It is simply the various processes,
procedures, methods and instrumentalities, by which data are secured,
specified, collated, processed and analysed Fasakin, (2000).
PURPOSE OF RESEARCH
Researches are often carried out in an attempt to survey, analyse
and replan an existing situation to produce positive effects(s). This is
achieved through a systematic process of data collection, presentation,
analysis and interpretation (Okoko, E. E. (1998). The subsequent information
and deductions from the research is implemented into planning proposals and are
likely to influence one’s proposals in solving problems in view.
In most cases, researches are meant to give necessary information
on the problem and the feasibility that the proposal put forward is workable.
This must be well backed by survey data
METHODS OF SAMPLING
Any attempt to collect data from all the professionals in the
building industry and from all the people living in interlocking brick
buildings in the south-western Nigeria will be technically and economically
ambiguous, wasteful and time consuming. It is therefore desirable to adopt a
sampling process that will be suitable for the targeted population and study
area. Four sampling methods were identified by Boyd et al. The sampling
techniques are simple, random, systematic and multistage sampling which is also
known as cluster sampling method.
In multistage sampling, there is the classification of the study
population into compartments or zones which are mutually from which the desired
sample can be selected. Kitchin and Tate (2000), contends that sample size
depends on the variability of the population to be sampled. He established that
one can only estimate the size of sample needed in order to estimate population
value with a certain degree of confidence if one already knows something about
the variability.
MULTISTAGE SAMPLING
Housing inventory (studies particularly in cities) normally
involves large coverage areas sometimes separated by hundreds of kilometers far
apart from each other. In most cases, locating and getting to a sampling unit
is expensive while measurement of each unit is relatively cheap. It would be of
advantage to concentrate measurements on a few locations. Multi-stage sampling
or sub-sampling has the objective of trying to provide a sample unit that can
be cost efficiently measured and to cluster these samples in higher level
larger unit to reduce the travel cost between measurement units Nichols (1979).
Loetsch and Haller (1973), described cluster sampling while the two words were
used interchangeably by Cochran (1997).
Multi-stage sampling has a member of advantages over simpler
methods. For instance, Yates, (1960) noted that sampling introduces flexibility
into sampling and it enables existing natural divisions and sub-divisions of
the population to be utilized as units at the various stages. Husch et al,
(1982) claimed that two-stages sampling may result in the reduction of
non-sampling errors since there is closer supervision and control of field work
when sampling units are concentrated in few locations. Also, two-stage sampling
yields estimates of a required precision at a lower cost than single-stage
sampling. Precision and cost both increase as the number of primaries is
increased and the number of secondary per primary may cut down cost, although
precision will suffer. Freeze (1965), further suggested that the greatest
precision for a given cost could be achieved by determining and taking an
optimum number of secondary per primary.
RESEARCH TOOLS
These are essentially the practical methods and ways of getting
information about a subject matter from the different sources available. These
include among many; observation, interview, questionnaire, ocular presentation.
These various methods are discussed below.
OBSERVATION
Someone once said “you can learn more by watching”. This method
does not require verbal or written approach on the source. There, the observant
only needs to watch events happen and record observations. Observed issues may
either be behavioural or non-behavioural whereby the former involves the
observer to participate in the event for “to catch a monkey, you behave as
one”. He acts as a part of the system and this gives him uninterrupted access
to information. While the later does not involve as much effort as the former.
He just has to watch and observe happenings.
INTERVIEW
This brings the researcher and the source to a face to face
conversation where a list of questions are prepared by the researcher and
thrown to the respondent according to the level of complexity of those
questions. The reliability of this method lies in the fact that verbal and
non-verbal responses are recorded and one can also ask questions outside the
ones already listed by the researcher. Also, expressions on the respondent’s
face can be judged when some certain questions are asked.
QUESTIONNAIRE
There are set of questions are designed by the researcher to
elicit some specific information on a particular matter, it is called
questionnaire. These set of questions are later collected, analysed and
presented for use in the testing of hypothesis. This is very advantageous in
the sense that it is time saving. It can cover a larger population than
interview.
TYPES OF DATA
There are different types of data collected from the site, field
or any other relevant source, which needs to be analysed as soon as collected. The
various types include:
PRIMARY
DATA: These are often referred to as raw data, gotten by the
researcher through the use of any of the above mentioned research tools. It is
also extracted directly from the various sources such as the respondent and the
area(s) under study. The questionnaire administered were sixteen (16) questions
with options and fill in the gap. Questions were asked to find out about affordability,
availability, cost of construction and maintenance cost of the . Personal
interview involved many people residing in interlocking brick buildings and
masons who are specialized in the use of interlocking bricks in building
construction. The interlocking bricks dwellers were interviewed on the
durability and sustainability of the material as a walling material.
Masons were interviewed on the period of construction,
availability of the material, method of construction and probable effect of
weather and human forces on the standing wall, and how to maintain them for a
long life. Some developers were also spoken with in the bid to get information
on the cost of production and its effectiveness in solving the housing need of
low income earners in the south western Nigeria. Observation and photograph
taking were carried out on interlocking bricks, interlocking bricks production
and interlocking brick construction sites to demonstrate the level of awareness
and use of this building material.
SECONDARY
DATA: These are the processed
information and kept in record for different purposes. They exist in published
materials and are merely collected for the purpose of research. In this regard
the researcher will explore the general use and production of interlocking
blocks in the state
EXPECTED CONTRIBUTION TO KNOWLEGDE
It will, perhaps
not surprising in these times of increased awareness of the impact that we have
upon the earth, that there is a burgeoning desire and movement to construct our
buildings from materials that are from the earth; using methods that are
simple, non-invasive and self-reliant. There are building materials that suit
every climate, every aspiration and every purse.
The research
will also revealed that the south-western part of Nigeria is endowed with
lateritic soil which is suitable for laterite fabricated materials such as
stabilised bricks, ceramic tiles, roofing tiles, clay pipes and brick facing
and most importantly interlocking bricks. The large scale production and use of
interlocking bricks in building construction will immeasurably boost the level of
industrialisation and job opportunities and most importantly make building
affordable for the people in the south-western part of Nigeria.
The research
will also shed more light on building materials, their peculiarity and
availability in this particular region or location. It will be hope that this
material, with the discussed attributes and merits will in great measure be put
into large scale building project such as the mass housing project for Ala
Quarters residents.
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