Construction Mgt
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Transcript of Construction Mgt
UNIVERSITY OF NIGERIA, ENUGU CAMPUS
FACULTY OF ENVIRONMENTAL STUDIES
DEPARTMENT OF ARCHITECTURE
CONSTRUCTION MANAGEMENT AT THE PREDESIGNED
PHASE
A seminar submitted in partial fulfillment of the requirements
of the course Construction Management (ARCT. 613)
By
ONWUJI, R.C
(PG/MSC/02/36668)
Lecturer: ARC.UZUEGBUNAM
July 2004
Table Of Contents
Introduction----------------------------------------------------------------------------------4
1.0 Project Feasibility Analysis--------------------------------------------------------------6
2.0 Site Selection ---------------------------------------------------------------------------6
3.0 Site Investigation -----------------------------------------------------------------------7
3.1 Site Surveys------------------------------------------------------------------------------7
3.2 Geotechnical Investigation------------------------------------------------------------8
3.3 Drainage And Utilities Survey---------------------------------------------------------8
3.4 Traffic Survey----------------------------------------------------------------------------8
3.5 Adjacent Property Survey--------------------------------------------------------------8
3.6 Archaeological Survey-----------------------------------------------------------------9
3.7 Environmental Issues-------------------------------------------------------------------9
3.8 Legal Aspect-----------------------------------------------------------------------------9
4.0 Design Criteria------------------------------------------------------------------------11
5.0 Master Schedule-----------------------------------------------------------------------11
6.0 Cost Plan And Cost Control---------------------------------------------------------12
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6.1 Creation Of Project Cost Control And Estimating System------------------------12
6.2 Cost Control Procedure--------------------------------------------------------------13
6.3 The Area Method---------------------------------------------------------------------15
6.4 The Cube Method---------------------------------------------------------------------15
6.5 The Unit Rate Method----------------------------------------------------------------15
6.6 The Approximate Quantities Method-----------------------------------------------15
6.7 The Effects Of Poor Cost Control---------------------------------------------------16
7.0 Building Codes------------------------------------------------------------------------16
7.1 Local And Federal Regulations------------------------------------------------------17
8.0 Preparation Of Environmental Impact Assessment-------------------------------18
Conclusion---------------------------------------------------------------------------------19
Reference-----------------------------------------------------------------------------------20
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INTRODUCTION
Construction management can be defined as the planning, control
and co-ordination of a project from inception to completion. This is
aimed at meeting the client’s requirements in order that the project
will be completed on time within authorized cost and to the required
quality standards.
Construction management starts by gaining an understanding of the
client’s objective and by providing the expertise to allow the client to
define more precisely what is needed and how it can be achieved. In
this way, construction management can influence the decision on the
type of facility required, its use, user needs, architectural concepts,
construction time scale and cost criteria.
The client can also be guided around such obstacles as unavailability
of relevant project resource and be advised on how to buy best, to
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develop existing facilities, to consider alternative locations, to evaluate
materials and constructing method as well as being advised of
potential cost involved in overcoming specific problems.
These considerations help the client in establishing a comprehensive
project brief which highlights the parameter of cost, time, quality,
facility function and specifies the contractual aspects and applicable
agreements.
The brief is important as it constitutes the basic reference document
for the project and is a formal specific expression of what is required
from the project. Therefore, the client must commit adequate time and
resources to its preparation. The brief can have minimal changes once
the detailed design starts. It must give sufficient details and enough
information to allow the consultants/design team to finalize the
conceptual design.
At this stage, the client and the project manager meet and agree
on:
The bases for the feasibility and strategy stages;
An outline Master schedule and cost plan;
A subsequent action plan for the project;
The terms and timing for the appointment of the Project Manager
Other services that might be offered at this time to assist the client
include:
Reviewing and participating in the drafting of legal and financial
documents to check on the consistency of definitions and
terminology. This includes an assessment of legal issues relating
to; contracts, land, financial arrangement, insurance and
taxation.
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Investigating planning authority approvals and the outline
strategy for implementation.
The valuation and acquisition of land for the project.
Preliminary assessment of the cost/value of the facility (type of
building/construction and standards of finish).
Initiating first cost plan/ budget limits and cash flow forecast.
Developing finance options and negotiating on funding.
Identifying professional Team members and deciding the basis of
their appointment.
Preparing terms of reference/conditions for the members of the
professional team essential for the feasibility studies and their
selection/ appointment.
Monitoring the professional team’s studies/work against the
programme and cost plan.
Coordinating the preparation of the feasibility report and
recommendations.
Reaching a decision about project viability based on the report
and recommendations.
1.0 PROJECT FEASIBILTY ANALYSIS
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This is a study undertaken to assess whether a planned project is
likely to be practical and successful and also estimating its cost. A
study of feasibility may show that a practical solution to the basic
programme can be developed, but there is always a tendency for client
and architect to be prematurely biased towards a particular solution. If
feasibility studies are to be valuable, there must be several
alternatives prepared from an equal base line which therefore permits
comparative analysis, and in the process may bring forward ideas not
previously thought of. This means that no one feasibility study can
represent a solution, but several, on analysis, will confirm certain
criteria which a final solution requires.
A market survey is done during the feasibility stage. Here, the
architect gets an idea on the types, quality and cost of material, labour
to be used during the construction. These choices are made as a result
of experience obtained from previous similar projects
During a feasibility analysis the following criteria should be
observed:-
The site and its permissible coverage.
Town planning regulations.
Density regulations related to maximum heights and floor space
indices.
Approved points of access to the site, which were limited by
limited by the major peripheral roads.
2.0 SITE SELECTION
Site selection is important stage in the project cycle where the client
does not own the land to be developed. It should be effected as early
as possible and ideally in parallel with the feasibility study. The work is
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carried out by a special consultant and monitored by the project
manager. This is to ensure that the requirements for the site are
defined in terms of the facility to be constructed, that the selected site
meets these requirements and that it is acquired within the constraints
of the project programme.
3.0 SITE INVESTIGATION
The architect should investigate the history of the site through official
sources as well as consulting local inhabitants – particularly in the case
of a rural site. The history of adjacent sites should also be investigated
to determine whether they enjoy any right acquired by prescription or
under agreement. The history of site could also reveal that the land
consists of made-up ground and it is liable to subsidence, necessitating
special precautions in the design of foundations. The client should be
advised on the implications at the early stage, for instance, building on
a water-bearing soil which may involve piling operations.
Other considerations include orientation, shelter, existence of
services like sewers, electricity, water, means of access to public
highway and communication. Finally, the topographical and other
features of the site have to be recorded; the levels, dimensions,
benchmarks if any, position and types of trees existing buildings both
on and adjacent to the site, overhead cables, and any other physical
features which will influence the design or siting of the proposed
building.
The activities involved in a site investigation can be broadly grouped
as;
3.1 SITE SURVEYS
Location
Ordinance survey reference
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Ground level/contours
Physical features
Existing boundaries
Adjacent properties
Site access
Structural survey
Previous use of site
3.2 GOTECHNICAL INVESTIGATION
Trial pits
Bore holes and bore hole logs
Geology of site including underground workings
Laboratory soil test
Site test
Ground water observation and pumping test
Geophysical survey
3.3 DRAINAGE AND UTILITIES SURVEY
Existing site drainage(open ditch, culvert or piped system)
Extent of any other utilities that may cross the site (oil pipelines,
water, electricity)
3.4 TRAFFIC SURVEY
Examination of traffic records from local authority
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Traffic counts
Traffic patterns
Delay analysis
Noise levels
3.5 ADJACENT PROPERTY SURVEY
Right of light
Party wall agreement
Schedule of conditions
Foundations
Drainage
Access
Public utilities serving the property
3.6 ARCHAELOGICAL SURVEY
Examination of records
Archaeological remains
3.7 ENVIRONMENTAL ISSUES
Effects of proposed development on local environment;
environmental impact assessment, where appropriate
3.8 LEGAL ASPECT
Ownership of site
Restrictive covenants
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Easements, e.g. rights of way, rights of light agreement
Way leaves
Boundaries
Party wall agreement
Highway agreement
Local authority agreement
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FLOW CHART USED FOR EACH OF THE ACTIVITIES OF SITE
INVESTIGATION
4.0 DESIGN CRITERIA
ADVISE CLIENT OF THE NEED
REVIEW WITH CLIENT
AGREE COST AND DATE FOR
COMPLETION
DOES SCOPE OF WORK ADEQUATELY
REFLECT SITE CHARACTERISTICS
DEFINE SCOPE OF INVESTIGATION
AND AGREE WITH CLIENT
SELECT SUITABLE ORGANISATION TO
CARRY OUT INVESTIGATION
IS ADDITIONAL INVESTIGATION
REQUIRED
INSTRUCT ADDITIONAL
INVESTIGATION
AGREE REVISED DATE FOR
COMPLETION
REVIEW REORT & ADVISE CLIENT OF
POTENTIAL RISKS & LIABILITIES
MONITOR PERFORMANCE AND
PREPARATION OF FINAL REPORT
HAS CLIENT INSTRUCTED
INVESTIGATION
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This involves style development in buildings relating to our up-to-
date technical opportunities, and designers face a barrage of possible
structural solutions, and a great number of alternative building
materials.
Quality design styles should be adapted such that the buildings will
remain very adaptable over a long period of time. In other to achieve
this, building design criteria should therefore aim at:
Modifying the climate
Supporting patterns of activity
Adding to our resources
Providing delight
5.0 MASTER SCHEDULE
A schedule of work form inception stage to completion stage. It
involves schedule of material, labour, cost and work schedule. Other
schedules can be drawn from here depending on alterations made.
Since the project is expected to be realized within a time frame and
budget, the master schedule should be drawn to guides the project
manager and give him responsibilities to monitor the progress of the
project from inception to completion.
The master schedule should be developed and agreed with the client
and members of the professional team concerned and detailed
programme for each stage of the project prepared as soon as the
necessary parameters are established.
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6.0 COST PLAN AND COST CONTROL
Cost plan is important at this stage as it provides the best estimate of
the final cost of the project. It is the plan of what the money will be
spent on and when. The cost plan should, therefore, include the best
possible estimate of cash flow for the project. It should cover all stages
of the project.
Cost control is a method of controlling the cost of a building project
within the limits of a predetermined cost through the design and
construction stages.
6.1 CREATION OF PROJECT COST CONTROL AND ESTIMATING
SYSTEM
The objective of cost control is to allow the project to be completed
within the approved budget. Cost reporting will facilitate at all times
the best possible estimate of:
The final cost of the project;
The future cash flow;
The cost in the use of the completed facility
Monitoring expenditure to date does not exert any control over future
expenditure and, hence, the final cost of the project. Effective cost
control is only obtained when the whole of the project team has the
correct attitude to cost control, i.e., one which will enable fulfillment of
the client’s objectives.
Effective cost control will require the following actions to be taken:
All decisions taken during design and construction are based on a
forecast of the cost implications of the alternatives being
considered, and that no decisions are taken whose cost
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implications would cause the total budget to be exceeded,
including appropriate contingency allowances.
The professional team should be encouraged to design within the
cost plan and adopt the variation control procedure for the
project, which is based on the architect’s instruction. Increased
costs on one item must be balanced by savings on another.
Adjustment of the cash flow plan results from an alteration in the
target cost, master programme or the forecast of inflation.
The variation control procedure is strictly followed at all stages of
the project. Only during the construction phase, when it can be
demonstrated that significant delay, cost or danger would have
been incurred by awaiting responses to the proposal from
interested parties, may the procedure be carried out
retrospectively. In this situation the matter must be discussed as
fully as possible and a site instruction issued.
Contingency money should be used only to pay for events which
are unforeseen. It should not be used to cover changes in the
specification or in the client’s requirement or for variation
resulting from errors or omissions. If the professional team
considers that there is no alternative but to exceed the budget, a
written request to the client must be submitted. This must
include; details of variation leading to the request; confirmation
that the variations are essential; confirmation that compensating
savings are not possible without having an unacceptable effect
on the function of the completed project.
Ascertain that the project costs are always reported back against
the original approved budget. Any subsequent variations to the
budget must be clearly indicated in the cost reports.
6.2 COST CONTROL PROCEDURE
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There are three main arrangements in the cost control procedure of a
project and any of these depends on the cost limit of the client.
The client will prescribe the programme requirements and also
establish the cost limit, these requirements are cost limits are
discussed with the architect and general information on known cost of
similar building projects is obtained by the architect. Once the basic
form of the building is decided, the quantity surveyor will prepare an
estimate taking full account of shape, number of storey and structural
form. The estimate may be based on any of the following methods of
approximate estimate: -
The area method
The cube method
The unit rate method
The approximate quantities method.
Any of these methods will be based on the information available but
assumptions will have to be made on finishing, fittings, services and
similar matters. By the end of the sketch (design) plan stage a more
accurate estimate will be prepared usually based on approximate
quantities and also comparative cost of alternative forms of
construction, services arrangement and so on should be available for
client’s approval. During the detailed design, the cost of the project can
be influenced by the choice of material and construction methods.
Continual reference to the cost plan is important on the details of
each point of the project are finalized with possible adjustment to the
design or distribution of cost to the elements as the process of
reconciliation proceeds. A final overall cost check can be made when
the design stage is complete.
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The second arrangement operates more when the client has
considerable experience of past cost of similar buildings. Just like in the
first arrangement, it is important to check the accommodation
requirement against the cost limit to be sure that the project is
feasible. Comparison is made with the known cost of similar buildings.
All other procedure applicable to the first arrangement is also
applicable.
The third arrangement applies to where available funds are limited
and the client wishes to carry out as much building work as possible.
He may prescribe a cost limit and ask the architect for details of the
size and quality of the building which can be provided with the
available fund. It is necessary to compute the amount of floor area that
can be provided by reference to the known cost of floor areas of similar
buildings. All other procedures applicable to the first arrangement are
also applicable here.
6.3 THE AREA METHOD
In this method, the architect estimates the cost of the building using
floor area of the spaces in the building with the qualification that the
user, site conditions, construction and type of finish must be
considered. Therefore, if a building is to be erected similar in these
respect to one built, it should be possible to relate its price to that of
the first one in proportion to the floor area also bearing in mind
fluctuation in cost of labour and materials which may have occurred in
the interval. The more dissimilar the buildings are in their character,
the more difficult comparison becomes.
6.4 THE CUBE METHOD
The idea behind this method was probably that the cube reflects
variation in height of storey which the area method does not.
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6.5 THE UNIT RATE METHOD
Certain types of building, such as hotels, church or theatres, lend
themselves to estimate based on a price per bed, place or seat. Such
estimates must be very approximate and vary according to the type of
construction and finish.
6.6 THE APPROXIMATE QUANTITIES METHOD
In this method, the approximate quantities are taken leaving out all
the minor items and grouping items together where practicable.
Normal foundations will be measured per linear metre, to include
excavation, concrete and brick work,. Walls will include internal and
external finish and windows be measured as extra over walls to include
glass, paint, etc. with this method, an approximate bill of quantities can
be prepared and priced.
6.7 THE EFFECTS OF POOR COST CONTROL
When the contractor is not interested in proper controls, he is open
to losses from many quarters. These include;
Low bids
Increases in cost of labour and materials.
Lack of sufficient knowledge of processes
Poor selection and matching of construction equipment
Adverse weather conditions – usually a contractor is expected to
make allowance for predictable weather conditions.
Inefficient management and supervision.
7.0 BUILDING CODES
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They are laws regulating the construction of buildings and prescribing
minimum requirements for fire protection, sanitation, and safety. Such
laws are intended primarily to set standards for new construction but
also to prevent the continued use of buildings deficient in these
respects. These codes served as guides in the enactment of local
building laws, which now contain most of their important provisions.
The trend toward unification of such building codes has increased,
leading to the development of regional codes, which serve groups of
municipalities, and state building codes.
The architect must be thoroughly familiar with the building codes
because it influences his practice and procedure as well as cost of
construction. An architect going into new locality should first of all
familiarize himself with the building codes This is logically a part of his
general inspection of the site as two adjacent communities might not
have the same building code. Fees for the issuance of building permit
and for inspection by the building commissioner’s office are usually
required. The architect should ascertain these costs as part of his
general inspection.
7.1 LOCAL AND FEDERAL REGULATIONS
Building regulations are laid down details of condition which are to be
complied to before approvals can be obtained. The architect should put
this into consideration during the design stage to enable the planning
authority to approve the drawing before construction starts. A
summary of some of these regulations include:-
The plans must comply with a particular city’s master
plan .Where such a master plan is not in existence, they must
comply with the land use plan.
The planning agency checks that multiple projects are not
approved for the same piece of land.
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Details on number of copies of plan to be submitted, assessment
and registration fees to be paid when found satisfactory.
All commercial buildings must have 6meters free space on all
sides.
Buildings should have a minimum front setback of 6 meters,
minimum side set back of 3 meters and minimum rear set back of
3 meters.
There should be a minimum distance of 6 meters between two
buildings on the same plot or not less than ½ times the height of
the buildings, whichever is higher.
Protected sites: no plans are approved where there are historic
building or monuments, open spaces, schools, etc.
Buildings must be designed by a registered architect and if it is
more than one floor, it must have a structural drawing designed
by a registered structural engineer.
Rooms for residential purposes should have windows as a means
of ventilation and lighting, which should amount to not less than
1/6th of the floor area served.
The planning authority has the power to stop order at anytime that it
is found that there are some irregularities in the plan approval.
8.0 PREPARATION OF ENVIRONMENTAL IMPACT ASSESSMENT
Environmental impact assessment is a national procedure for
evaluating the likely impact of a proposed activity on the environment.
It is important to assess the environmental impact of construction
activities at an early stage of planning. This assessment is prepared for
plans involving: -
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Residential land in excess of 2 hectares
Mixed development ,e.g. schools, churches, hospital, housing
estates industries and commercial development
A public building or office building in excess of four floors of 5000
square meters of lettable space.
A petrol filling station
A major recreational development
They are submitted along with other plans like survey plans for
approval.
CONCLUSION
With all these listed, we can now agree that construction
management at the predesigned stage entails a lot. This process is
21
very important in building construction as the clients requirements
are reached satisfactorily and in record time putting into
consideration the economic situation.
Hence, it can be said that that it is an organized sequence of
planning, control and coordinating a project at the inception stage.
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REFERENCE
Chartered institute of building (1992) Code of practice for project
management for construction and development.
Harper, R.H. (1990) Building, the process and the product, Berkshire:
The chartered institute of building.
Bassey, N. (1994) the management of construction, Nigeria: Kraft
book limited
Nigerian urban and regional planning decree 1992.
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