construction

The construction dissertation below has been submitted to us by a student in order to help you with your studies.

Types And Causes Of Construction Delays

This chapter gives an idea of what construction delays are, how are they defined and what are their types and comparison of them. Delays can be seen differently from different point of views. Causes of delays and categorization of them in various international contexts are also discussed.

2.2 DEFINING CONSTRUCTION DELAY

A lot of work has been done before on construction delays and every author came up with his/her own definition.

Assaf and Hejji defined delay as “Time overrun either beyond completion date specified in a contract, or beyond the date that the parties agreed upon for delivery of a project slipping over its planned schedule.” (Assaf, Hejji, 2006)

Stumpf defined delay as “Act or event that extends the time required to perform a task under a contract. It usually shows up as additional days of work or as delayed start of an activity.” (Stumpf, 2000). And many similar definitions were given.

Therefore construction delays can be considered as time lag in completion of activities from a fixed time as per contract or they can be defined as late completion or late start of activities to the planned schedule or contract schedule. When project delay occurs it means project cannot be completed within stated time, which means there will be extensions of time required which will further result in fine, increased cost due to inflation, termination of contract, court cases etc. or combinations of above stated factors.

Delay can be seen as risk for the project and could be handled at inception stage or at least one can try to mitigate or minimize it. Risk is an integral part of a construction project; it is well known that no project is risk free. If risk is analysed at inception or planning stage it could be managed, minimized, shared, mitigated or accepted to give some good results. Delay can be considered similar to risk or a type of risk; as no construction project is free from delays, delay is also integrated part of construction projects. It depends on size of project as well. Therefore it is expected to analyse and manage delay in same fashion as risk.

Delays are often result of a mismanaged event which must have been managed in a systematic process so as to analyse the effect of that event on the project and how to minimize chances of further delay. (Keane, Caletka, 2008).

2.3 CATEGORIZATION AND TYPES OF CONSTRUCTION DELAYS

Before getting on types of various construction delays there is a major categorisation which is required to be understood. Construction delays can be delayed in some major groups as listed below.

El-Saadi (1998) categorized delay in four major groups.

Critical or Non critical

Excusable or Non Excusable

Compensable or Non Compensable

Concurrent or Non concurrent

Alkaas S., Mazerolle M. and Harris F. (1996) and Ahmed S.M. et al gave following categorizations:

Excusable Delays

Excusable compensable delays

Excusable noncompensable delays

Nonexcusable delays

Concurrent delays

Fig. 2.1 Classification of delay based on their various attributes. Nuhu Braimah (2008)

To achieve objectives of this dissertation and to consider delay as risk it is necessary to know about these types of delays and as per categorization in what category they lie. This basic knowledge helps in moving forward and determining strategies to mitigate these risks. Now in this part we will discuss these types of delay in detail:

2.3.1 CRITICAL AND NON CRITICAL

In simple words Critical delays are those which cause delay to entire project completion date while Non critical delays not necessarily affect the project completion date but affects progress. In all the projects delays are considered at the project completion date. Delays can be combination of small and big delays that occurred during the whole project. Therefore critical delays are taken more into consideration then noncritical delays.

2.3.2 EXCUSABLE DELAYS

Excusable Delays occurs due to events which are outside the control of contractor like heavy rains, storms, strikes, fire, client suggested changes, differing site conditions, change of government policy or their intervention, stakeholder intervention etc.

Alkass S. et al (1996) says that when there are excusable delays, contractor is entitled to time extension in case date of completion is extended. Such delays can also affect non critical activities which must be considered with more detailed analysis or adjustment of float time.

Excusable delays can be further classified in compensable and noncompensable delays.

2.3.2.1 EXCUSABLE COMPENSABLE DELAYS

As name suggests excusable compensable delays are those in which contractor is entitled for extra payment (compensation) i.e. monetary compensation and time extension as well. But decision that a delay is compensable or noncompensable is taken as per contract between client and contractor. Natural disasters or some reasons which are out of control are not considered. Example of such delay could be that client doesn’t allow access to site even after notice to proceed is given; other such delays which are due to client are compensable.

2.3.2.2 EXCUSABLE NONCOMPENSABLE DELAYS

Such delays are such where both contractor and client are not responsible for delay. Under such circumstances only time extensions are granted and no monetary compensation is provided. Such delays include act of God.

2.3.3 NON EXCUSABLE DELAYS

As name suggests these delays are such that they don’t have any excuse or no excuse can be given for them. They arise due to carelessness or actions and inactions of contractors and subcontractors. For such delays no time extensions and monetary compensation is given to contractor if it has affected whole duration of project. In such cases client is liable to get liquidated damages. Example of such delay could be constructing something wrong which is not given in drawings, not completing work on time, improper resource allocation etc.

2.3.4 CONCURRENT DELAYS

This is the most complex categorization of delay as it consists of two or more kind of delays regardless of their type which occurs at same time or overlaps some duration together. It is necessary to find out what type has caused overall delay in project completion. Therefore different factors like time of occurrence of delay, duration of delay, impact of them, float ownership etc. have to be considered carefully.

Alkass et al (1996) said that; Concurrent delays which contains two or more excusable delays results in time extension. When compensable and nonexcusable delays are concurrent a time extension can be given or delay can be distributed between client and contractor.

2.4 CAUSES OF CONSTRUCTION DELAYS

In section 2.3, categorisation of delays was discussed. Now in this section will deal with causes of delays. Lot of work has been done on understanding causes of delays. The two major categorization of delay causes one is Internal Cause another is External Cause.

Internal cause includes delays caused by parties involved in construction project like Client, Contractor, Designer, Consultant these are four major parties then Subcontractors, material suppliers etc. comes. From external factors it includes act of God, strikes, stakeholder’s dissatisfaction etc.

Assaf and Hejji (2006) reflected various causes of delays which occur in large construction projects. They had a field survey of 23 contractors, 19 consultants, and 15 owners and found out and reflected on 73 causes of delays under eight different groups. All those 73 factors are given in table below.

NO.

CAUSES OF DELAY

GROUP

1

Original contract duration is too short.

Project

2

Legal disputes b/w various parties.

Project

3

Inadequate definition of substantial completion.

Project

4

In effective delay penalties.

Project

5

Type of construction contracts.

Project

6

Type of project bidding and award

Project

7

Delay in progress payment by owner.

Owner

8

Delay to furnish and deliver the site to contractor by the owner.

Owner

9

Change orders by owner during construction.

Owner

10

Late in revising and approving design documents by owner

Owner

11

Delay in approving shop drawings and sample materials

Owner

12

Poor communication and co-ordination by owner and other parties

Owner

13

Slowness is decision making process by owner

Owner

14

Conflicts between joint ownership of the project

Owner

15

Unavailability of incentives for contractors for finishing ahead of schedule

Owner

16

Suspension of work by owner

Owner

17

Difficulties in financing project by contractor.

Contractor

18

Conflicts in subcontractors schedule in execution of project

Contractor

19

Rework due to errors during construction.

Contractor

20

Poor site management and supervision by contractor

Contractor

21

Poor communication and co-ordination by contractor with other parties

Contractor

22

Ineffective planning and scheduling of project by contractor

Contractor

23

Improper construction methods implemented by contractor.

Contractor

24

Delays in subcontractors work

Contractor

25

Conflicts between contractor and other parties

Contractor

26

Inadequate contractors work.

Contractor

27

Frequent change of subcontractors due to their insufficient work.

Contractor

28

Poor qualification of the contractors technical staff

Contractor

29

Delay in site mobilization.

Contractor

30

Delay in performing inspection and testing by consultant

Consultant

31

Delay in approving major changes in the scope of work by consultant

Consultant

32

Inflexibility (rigidity) of consultant

Consultant

33

Poor communication and co-ordination by consultant with other parties

Consultant

34

Late in reviewing and approving design documents by consultants

Consultant

35

Conflicts between consultant and design engineer.

Consultant

36

Inadequate experience of dsigner.

Consultant

37

Mistakes and discrepancies in design documents

Design

38

Delays in producing design documents

Design

39

Unclear and inadequate details in drawings

Design

40

Complexity of project design

Design

41

Insufficient data collection and survey before design

Design

42

Misunderstanding of owner’s requirement by design engineer.

Design

43

Inadequate design team experience

Design

44

Un-use of advanced engineering design software.

Design

45

Shortage of construction materials in market

Material

46

Changes in material types and specification during construction

Material

47

Detail in material delivery.

Material

48

Damage of sorted material while they are needed urgently.

Material

49

Delay in manufacturing special building material

Material

50

Late procurement of materials

Material

51

Late in selection of finishing materials due to availability of many types in market

Material

52

Equipment breakdowns

Equipment

53

Shortage of equipment

Equipment

54

Low level of equipment-operator’s skill

Equipment

55

Low productivity and efficiency of equipment

Equipment

56

Lack of high technology mechanical equipment

Equipment

57

Shortage of labours

Labours

58

Unqualified workforce

Labours

59

Nationality of labours

Labours

60

Low productivity level of labours

Labours

61

Personal conflict among labours

Labours

62

Effects of subsurface conditions

External

63

Delay in obtaining permit from government

External

64

Hot weather effects on construction activities

External

65

Rain effect on construction activities

External

66

Unavailability of utilities in site

External

67

Effect of social and cultural factors

External

68

Traffic control and restriction at job site

External

69

Accident during construction

External

70

Differing site conditions

External

71

Changes in government regulations and laws

External

72

Delay in providing services from utilities

External

73

Delay in performing final inspection and certification by a third party

External

Table 2.1 Causes of delays as per group Assaf and Hejji (2006)

Their work gave a broad view over construction delays and their causes. Though their classification is quite broad, but it gives a more insight to various causes.

Odeh AM and Battaineh HT (2002) presented following 8 major groups of construction delay.

Client related factors which include finance, payment of billed work, interference in work, slow decision making etc.

Contractor related factors include site management, improper planning, insufficient experience, improper construction methods, insufficient and unskilled work force etc.

Consultant related factors include contract management, improper drawings, approval of drawings, tests at site etc.

Material related factors include availability, quality and shortage.

Labor and equipment factors include supply, productivity, equipment availability, failure etc.

Contract factors include changed orders and mistakes and disagreements in document.

Contractual relationship factors includes, disputes, negotiation, improper management of information system, improper work breakdown structure and task responsibility matrix.

External factors like act of god, strikes, accidents etc.

Most of the work done in field of causes of delays reflects similar causes of delays and 8 major groups. They all gave recommendations related to these factors but very few scholars suggested to forecast delay in planning stage. Khalil and Ghaftly (1999) said delay is important issue. In order to manage it more properly and to mitigate them deep investigation to this area is needed. Having idea of frequency, extent and responsibility of delay can provide insights of early planning to control these factors and improve project performance.

2.5 PERSPECTIVE FROM DIFFERENT COUNTRIES

Work from Chan and Kumaraswamy (2002) from Hong Kong industry gives four major causes of delay in Hong Kong industry which are as follows:

Project scope

Project complexity

Project Environment

Management related attributes

The above four factors were studied with their constituent casual factors to gain more insight and understanding of their significance. They were summarized in following figure:

Figure 2.3 Summary of principal factors affecting construction durations of projects

He gave another table comparing factors causing delay in construction projects in various economies. It gives an overview of common factors in these economies. It gives a clear understanding of various countries at once.

Factors Causing Delay

Countries where survey was conducted

US

UK

DEVELOPING COUNTRIES

TURKEY

NIGERIA

SAUDI ARABIA

HONG KONG

INDONESIA

Inclement weather

*

*

*

*

*

Labour shortage/ Low labour productivity

*

*

*

Poor subcontractor’s performance

*

*

*

*

Variations (design change/ extra work)

*

*

*

*

*

Unforeseen ground conditions

*

*

Materials shortage/ late material delivery

*

*

*

Inadequate construction planning

*

*

*

Financial difficulties

*

*

*

Delays in design work/Lack of design information

*

Poor site management

*

*

*

*

Impractical design

*

Poor communication

*

*

Inappropriate type of contract used

*

Lack of designer’s experience

*

Inaccurate estimating

*

*

*

Table 2.2 Source: Chan and Kumarswamy (2001)

Ogunlana and Promkuntong studied and compared construction industry of Thailand and other economies. Study involved delays experienced in the High Rise Building construction projects in Bangkok, Thailand. According to them Resource supply problem were most acute problems of the construction industry in boom years. Project suffered delays due to inadequate supply of cement, technical personnel were overstretched, and demands from owners to do frequent changes etc. are the major causes for delay in developing economy.

Sabasivan and Soon (2007) conducted study of causes of delay in Malaysian construction industry. They conducted a survey and 150 participants were involved. They came up with 10 most important causes of delay which are as follows:

Improper planning of contractor.

Poor site management from contractor

Inadequate experience of contractor

Improper payments and finance from client

Subcontractors problem

Material shortage

Labour supply

Failure and availability of equipment

Improper management information system

Mistakes during construction stage.

COUNTRY

RESEARCHERS

MAJOR CAUSES OF DELAYS

Saudi Arabia

Assaf et al

Slow preparation and approval of shop drawings

Delays in payments to contractors

Changes in design/design error

Shortages of labour supply

Poor workmanship

Lebanon

Mezher et al

Owner had more concerns with regard to financial issues

Contractors regarded contractual relationships the most important

Consultants considered project management issues to be the most important causes of delay

Saudi Arabia

Al-khal and Al-Ghafly

Cash flow problems/financial difficulties

Difficulties in obtaining permits

“lowest bid win first” system

Jordan

Al-Moumani

Poor design

Changes in orders/design

Weather

Unforeseen site condition

Late deliveries

Kuwait

Koushki et al

Changing orders

Owners financial constraints

Owner’s lack of experience in the construction business

UAE

Faridi and El-Sayegh

Slow preparation and approval of drawings

Inadequate early planning of project

Slow decision making of owners

Shortage of manpower

Poor site management and supervision

Low productivity of manpower

Saudi Arabia

Assaf and Al-Hejji

Change in orders by the owner during construction

Delay in progress payment

Ineffective planning and scheduling

Shortage of labour

Difficulties in financing on the part of contractor.

Hong Kong

Chan and Kumaraswamy

Project scope

Project complexity

Project environment

Management related attributes

Florida

Ahmed and Azhar

Design related

Construction related

Financial/economical

Management/ Administrative

Code related

Acts of God

Table 2.3 Summary of previous studies of the causes of delay in construction project some data from above table is taken from Sweis et al (2008)

2.6 SUMMARY:

A total of 73 factors and 8 major groups of causes of construction delays were identified through intensive literature reviews in order to consider maximum factors. These factors will be helpful in data analysis so as to forecast delay at planning stage and treat it as risk so that risk management methodologies can be implemented to delay so as to mitigate and minimizing it.

These eight major categories can be brought down as shown in figure.

Fig 2.4 Classification of delay groups.

All major 8 groups can be brought down to 2 major groups which are Internal and external causes. Internal is further subdivided in owner, consultant, contractor and resources. Resources are further subdivided in Material, equipment and labour.

Overall if we need to classify groups for the causes of delay 5 major groups covers all 73 factors they are Owner, Contractor, Consultant, Resources and External.

These causes and classification will help us to rank and treat delay as a risk at planning stage so as remedial measures can be applied. Though in spite of all studies and delay causes know till now it is hard to forecast delay because it’s very unpredictable, we can’t analyse frequency of delay due to some reason in a project. Sometimes external causes are so dominating that co-ordination of internal groups get disturbed and project faces delay.


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