The characteristic of construction
industry is uncertainties, unpredictability and susceptible to understandings
leading to delays. Delays in construction can affect the overall project
participants adversely. It is the common interest of all parties to avoid the
delay as much as possible at the first place and to minimize then even if the
delays arise. Davision and Mullen 1 gave the concept of delay as the
extension of time beyond planned completion dates traceable to the contractors.
While, Aibinu and Jagboro 2 defined the concept of delay as situation when
the contractor and the project owner jointly or severally contribute to the
non-completion of the project within the original or the stipulated or agreed
contractor period. The duration of project is normally specified by the owner
and contractors have responsible to ensure the completion of the project within
the owner’s time frame. Construction researcher and practitioners have recently
begun to emphasize the need for developing the concept of construction time
performance to be used by clients, consultants and contractors 3.
Nonetheless, delay in construction projects have still been found from articles
and research papers. Similarly, Chalab and Camp 4 conducted a review on
project delays in developing countries during planning and construction stage.
In their study, they found that the contractual disagreement caused both delay
and cost overruns on the early stages of construction. Rwelamila and Hall 5
found that the timely completion of a project was frequently seen as a major
criterion of project success. In Australia, Bromilow 6 found that only
one-eight if building contracts were completed within the scheduled completion
dates and the average time overrun exceeded 40%. Wilson 7 examined the role
of the owner and architect/engineer’s roles in the prevention delay and
resolution of construction claims. Wilson also summarized the causes of
construction claims which include change orders, adverse weather and unclear
is generally acknowledged as the most common, costly, complex and risky problem
encountered in construction project. Construction project
can be susceptible to considerable pressure on the time delay. Such pressure
environments lead to extension of time and cost. Delays in construction may be
caused by one or a combination of several reasons. It may start with a simple reason
and lead to a substantial set of interrelated complex disputes in contract
agreement. Most of the typical delays are caused by factors such as unrealistic
contract duration and cost, differing site conditions, change orders, delays,
impact and ripple effects of delays, evaluation the quality and quantity of
works, owner furnished items, difference in the interpretation of plans and
specifications, unfulfilled duties, acceleration, inefficiency and disruption
8-11. Facts about site conditions that are overlooked at the bidding stage
could increase the cost and the risk of disagreement. During construction
period, the conflict among owner and main contractor has become increasingly
prone activity. Cost overruns may amount to a substantial percentage of the
overall contract value and delays may reach disturbing proportions. The
allocation of risk among the owner, the main contractor and the designer is
stated in the construction contract. However, the construction contract is
typically prepared by the owner who ensures that a considerable portion of the
risk rests with the main contractor. The main contractor therefore faces a
multitude of risk among which are inflation, strikes, labor problems, adverse
weather, accidents, shortages of materials and staffs and unforeseen conditions
at the construction site. Imbalances in risk allocation may eventually end up
in disputes between involved parties and probably seek for settlement in court.
Over the past decades, construction practitioners have tried to develop and
implement the right contractual methods which fit the best approach of their
needs and minimizing delays in construction project. Nonetheless, construction
delays have still been found from research papers. Assaf and Al-khali 12
found extensive of 56 causes of disputes over delay identified and reported
that the contract disagreement was one of their main delay causes in large
building projects. Ayman 13 conducted a survey on causes of delay on public
projects in Jordan. The results indicated that designing, change orders,
weather, site conditions, late deliveries, economic conditions and increase in
quantity were the main causes of dispute and consequently delay construction
schedule. Similarly, Odeh and Battaineth 14 reported that interference,
inadequate contractor experience, financing and payment, labor productivity,
slow decision making were five most important causes of dispute and delay in
construction project with traditional contract. Kululanga et al., 15
identified four sources of delay in construction; errors, defects and omissions
in the contract documents, underestimating the real cost of the project in the
beginning, changed conditions and stakeholders involved in the project. In
fact, no project can be considered shielded from a potential delay. Such delay
can lead to significant financial damages. The degree of delay is depended on
its nature of cause, content and complexity of contract agreement. Walton and
Dutton 16 found that conflicts in inter-organizational resulting in low trust
and low respect which in turn has an adverse impact on performance. It required
an effort and support from legal, design and construction team in order to
mitigate the threat of delay among construction team. Therefore, the delay
should be clear and understood by all parties, especially the main contractor
so that they know how to avoid delay risks in a way that agreed completion of
project date can be met.
The data collection process involved two
stages. The first stage consisted of literature reviews for information on the
causes of delay in other countries and non-structured interviews of 15 key
players involved in the implementation process. The purpose of interviewing the
key players was essentially to validate a preliminary set of construction delay
causes gleaned from the literature and to determine from their experience other
factors which cause construction delay in buildings projects in Singapore. This
phase resulted in the identification of thirty-five (35) delays factor. The second
stage involved the development of questionnaire incorporating the 35 delays
identified and data collection. The questionnaires comprised open-ended and
closed-ended questions. A hand-delivered questionnaire method was used in order
to mitigate the low respondents. Questionnaire was divided into three main
parts. The first part was an introduction to explain the idea and purpose of
the survey as well as the definition of the interested area of study. The
second part contained general information questions including annual volume,
specialization, experience and nationality of the company. The third part
concerned the delay factors in building works projects. For each question, the
respondents have five options .These are, “most severe”, “severe”, “moderately
severe”, “fairly severe” and “none severe”. Furthermore, twenty-three of out
seventy-four respondents were also available to answer questions relating to
the questionnaire. The questionnaire was dispensed to each category of the
respondents-clients, consultants and main contractors. The convenience or
availability sampling approach was used in the selection of respondents. The
survey resulted were analyzed by using the severity index approach and the
Spearman’s rank correlation coefficient formula to measure the degree of
agreement in the ranking by contraction practitioners. The severity index was
helped to be an approximation to tolerance limit data, the degree of delay
tolerance to construction performance impact was needed, although there have
been as much or more work in this area of dispute tolerance as in other
countries. Based on the response to the survey, a severity index was calculated
to interpret the degree of seriousness effect of those problems. This index was
calculated as follows 17:
ai = constant expressing weight
given to ith response: i = 0, 1, 2, 3, 4
xi = variable expressing frequency of ith
i = response category index of 0, 1, 2, 3, 4
illustrated as follows:
x0 = frequency of very often response and
corresponds to a1 = 4;
x1= frequency of often response and
corresponds to a2 = 3;
x2 = frequency of moderate response and
corresponds to a3 = 2;
x3 = frequency of not often response and
corresponds to a2 = 1;
x4 = frequency of seldom response and
corresponds to a1= 0;
respondent to the survey has to select one weight (level of significance) for
each factor causing a delay. There are 5 level of weight, ranging from 0
(seldom to cause delay response) to 4 (very often to cause delay response). The
summations of all of the respondents’ answers are averaged using the Eq. (1).
Eq. (1) was used to calculate the severity index for all disputes factors. The
index was ranked for domestic and international funded public works projects.
The severity index was categorized into five levels. The 0-15.5% was
categorized as non severe; 15.5-38.5% is categorized as somewhat non-severe;
38.5-63.5% is categorized as moderately severe; 63.5-88.5% is categorized as
severe; and 88.5-100% is categorized as most severe. The categorizations
reflect the scale of the respondents answers to the questionnaire. The severity
index of a category was the average severity indexes of all its related
problems. As an example I, the average weighted perceived significance was computed as follows:
the collected information from the survey were examined and verified for their
correctness. Data cleaning was carried out by checking the frequency and
descriptive statistics as well as coding and data entry. The cleaned data were
then computed and analyzed to obtain frequency, statistical descriptive
analysis and variance. SPSS 12.0 was used for multiple comparison tests. The
results of the survey are shown in Table 4 and Table 5.
agreement The spearman’s rank correlation, was a non-parametric measure of
statistical dependence between two variables. It offered an advantage of not
requiring the normality assumption or homogeneity of variance assumption. The
subjected can be compared, as results have one or two outliers, their influence
can be negated. In this study, the relationship among different parties or
factors was measured. A perfect spearman correlation of +1 or ?1 occurred when
each of the variables was a perfect monotone function of the other. A +1
indicated a perfect positive relationship among respondents, whereas-1
presented that there was a negative relationship among their respondents
opinion. The spearman’s rank correlation coefficient, rs was used to measure
and compare between the rankings of owners and main contractors for a single
cause of delay. These results were used to test the significance level at 5%.
The coefficient can be computed as follows:
rs = Spearman’s rank correlation coefficient between two parties.
= The difference in ranking between ranks assigned to variables for each cause
(owner and consultants, owner-contractors, consultants- contractors), and
= The number of pairs of rank, equals to 35 and 4 for all the delay factor and
for the main categories of delays, respectively.
classification of construction delays were caused by several factors. Based on
literature reviews and interviews with
owners, consultants and main contractors in the related area of study resulted
in the identification of 35 common delay factors. In order to present the
identified problems; they were classified into four main delay groups. The
classification of main group was based on Assaf et al.’s 18 delay
classification; with slightly modified into contract and specification dispute,
financial dispute, environment delay and other common issue delay. Each group
reflects issues that have a common purpose.
Results and Discussions
The informations on
respondent among owners, consultants and main contractors with their response
rate were shown in Table 1. The total rate of response to the questionnaires
was 83%(66). The owners filled questionnaires with success rate of 83%(12) whilst
domestic and international main contractors and consultant companies filled
questionnaires with success rate of 88%(18), 95%(19) and 67%(15) respectively.
The evaluation of overall success rate was considered as excellent 17. Babbie
suggested that any rate of success over 50% can considerably be reported, while
the overall value above 60% and 70% can be mentioned as good and excellent
respectively. Information on type of building projects were shown in Table 2.
While, comparison severity issues in building projects were shown in Table 3.
These profiles indicated
that delays in building projects
were fairly common in Singapore. Table 4 showed comparison spearman rank
correlation and Table 5 summarized the responses in respect of the 5 most
delays factor in building projects. As far as 4 main delay categorizes were compared
in Table 5. The contract and specification delay category was rated as the
highest severity index by owner with severity of 56.4% while consultants and
main contractors had seen differently. Contract and specification delay
category was rated as second highest severity index by consultants and main
contractors with severity of 52.5 and 56.3% respectively. From interviewee’s
point of view, the payment was sometime delayed. This was due to mis-management
in cash flow of owner. The delay in payment caused difficulties to main
contractors in bringing the performance of completion as it was stated in
contract agreement. In multi-international funded projects, it further required
authorized representative persons from loan provider to sign necessary documents
as double-standard system before it could be further processed. The progress
payment was usually transferred to main contractor designated bank account
within 14 days after all requested documents had been approved by authorized
and Specification Delay Category
Interviewees expressed their
opinion on contract and specification delay category as delays mostly came from
contract and specification which required the provision of clear working
drawing. The violating condition of the contract must be monitored and
improved. Fair-contract should as much as possible be encourage. It might help
to minimize the violation of the contract. While consultants and main
contractors gave their expression on contract and specification delay category
as sometime contract was weak and specification was unclear. These caused
further discussion among owner consultant and main contractor which caused
delay in progress if owner had not finalized the project.
It was worth to point out that
change orders in large construction project were a consequence of insufficient
working drawing details, inaccurate bill of quantities and unrealistic contract
durations which affect project durations during the execution of the project.
This cause the dispute and delay between owner and main contractor. The main
reason why considerable works have been frequently changed by most construction
owners is due to sufficient time and effort are not spent at the
preconstruction phase for feasibility studies, design and site survey and
Financial Delay Category
As far as financial delay
category was concerned, the result showed in table 3 that the delay in progress
payment by owner factor was rated as the mostly severe delay factor by owner
consultant and main contractor. The explanations were given by interviewees as
construction projects require steady and in-time payment from owner in order to
utilize the payment to pay off their expenses. Delay in payment would have
momentum on involved activities in construction projects. Work progress could
be delayed or even ceased if the payment had been prolonged. Furthermore, those
subcontractors had weaker in financial stability therefore ability to maintain
their works progress was low and vulnerable to went bankruptcy. This was
natural of businessman to worry about the payment even though owner had already
provided an evident to proof their ability to financial support throughout the
Adverse weather condition and
unforeseen problem underground factor were main concerned factors for owners
and main contractors. These factors caused delay for construction. In order to
alleviate the delay factors, proper investigate on historic background of
construction site should be deployed. Regarding to community health concern,
noise and dust pollution factor were becoming a concern issue among owners,
consultants and main contractors where construction site was located near high
buildings and residential areas. Noise and dust might cause inconvenience for
neighbors and pressing a complaint to local authority. Therefore, restricted
time was given to main contractors. Approval environment assessing impact from
local authority factor is now becoming another concern factor to owners, consultants
and main contractors.
Interviewees make a high
concerned on lack of skilled labors and engineers factor which owners expressed
their deep concerned on consequence of lacking of skilled labors and engineers
will effect to overall performance and progress of project as well as quality
of works. In order to alleviate the problems group, owners and the main
contractors should carefully review all aspects of project in order to ensure
that there was a minimum error. Respondents also agreed that inadequate in open
and factual communication between client and main contractor will lead to
construction delays and disputes as the owners and main contractor unable to
express the construction difficulties formally and in detailed so that
consultants able to give solution in timely manner. Therefore, both parties
should have a positive thinking and good-will when problems arose.
Conclusions and recommendations
The conclusion can be drawn from
studied and the results of the analysis of the survey delay problems in
building projects in Singapore as follows.
This study has identified and
classified 35 related factors of common delay in building projects in Singapore.
These common delay factors among owners consultants and main contractors. The
main delay category can be classified into 4 main categories: contract and
specification, financial, environment and other common.
All main delay categories and
their related delay factors were found to have frequency of very often response
on the relationship among construction practitioners, Nonetheless, the degree
of severity do vary.
Financial delay category was
evaluated as moderately severe level by construction practitioners. It appeared
that main contractors have paid their attention to financial greater than
contract and specification delay category which caused severely delay in
construction. Whist, owners gave their first attention to contract and
specification delay category which believed to cause severe delay in the
Initially lethargic attitude of management team
must be avoided. This is one of the main reasons for delay. Supply of material
at the site at the right time should be taken care by the site engineer.
materials must be made available as per requirement in advance.
concrete plants must be installed.
surveyor must be appointed.
holidays must be taken into consideration while scheduling.
yard must be build to store materials in site.
of payment from head office must be done as soon as possible.
frequent change of staffs.
in site should be appointed with experience in the same field.
to the labour must be given in the right time without fail because most of the
delay in the project is due to shortage in labour.
planning must be done in advance to avoid material supply delay since
material is also one of the major delay reasons.
of any material from head office must be done as soon as possible.
of resources from tendering department must be done in advance.
must be carried out in correct sequence.
required must be forecasted earlier by site engineer and ordered in advance.
planning details i.e. micro level planning must be provided by head office.
F. John Reh,
Manager, about money website