Work Breakdown Structure and Sequence of Work
The project team should be concerned with the effectiveness as well as the efficiency of the project. Effectiveness will be enhanced if there is more of an overlap in the roles played by design and construction so that each individual player may take action in the light of a greater understanding of client requirements.
2.3 Sequence of Work
Table 2.1c Courtesy: (Chudley and Greeno, 1999) Sequence of work for building construction
NO SEQUENCE OF WORK
SUBSTRUCTURE WORK
1 FOOTING
2 Caisson Excavation
3 Drilling Cassion
– 4 Prefabricated Steel Casing
– S Installation Temporary Steel Casing
6 Remove water from Hole
– 7 Installation Reinforced Bars
8 Pouring Concrete Work
9 Concrete Vibration
10 FOUNDATION
Table 2.1c: Continued
ii Positioning Formwork
12 Prefabricated Reinforcement Bar
13 Installation Reinforcement Bar
14 Pouring concrete
15 Concrete Vibration
16 Curing Process
17 Striping Concrete Formwork
18 GROUND FLOOR BEAM
19 Positioning Formwork
20 Prefabricated Reinforcement Bar
21 Installation Reinforcement Bar and Plumbing
22 Pouring concrete
23 Concrete Vibration
24 Curing Process
25 Striping Concrete Formwork
26 GROUND FLOOR SLAB
27 Cleaning of Slab Form
28 Positioning Formwork
29 Prefabricated Base Reinforcement Concrete (BRC)
30 Installation of Base Reinforcement Concrete (BRC)
31 Pouring Concrete
32 Concrete Vibration
33 Curing Process
34 Striping Concrete Formwork
SUPERSTRUCTURE
1 GROUND FLOOR COLUMN
2 Prefabricated Steel Cage of Column
3 Installation Steel Cage
– 4 Column Rebaring
5 Column Plumbing
6 Cleaning of Column Form
7 Positioning Formwork
8 Pouring Concrete
9 Concrete Vibration
10 Curing Process
11 Striping Concrete Formwork
12 STAIRCASE CONSTRUCTION
13 1 Positioning Formwork
I
Table 2.1c: Continued
Prefabricated Steel Reinforcement Bar
T15 Installation Reinforcement Bar
Poured Concrete
17 Concrete Vibration
18 Curing Process
– 19 Striping Concrete Formwork
20 GROUND FLOOR LEVEL WALL
CONSTRUCTION
– 21 Installation of reinforcement bar(wall height more
than3m)
22 Mortar mixed
23 Concrete Block Lying
24 ROOF CONSTRUCTION
25 Prefabricated Roof Trusses at Plant
26 Installation of Roof Trusses
27 Installation of Roof Membrane
28 Installation of Roof Covering
INTERNAL CONSTRUCTION and FINISHES
1 DOOR
2 Prefabricated Door
3 Installation of Door
4 WINDOW
5 Prefabricated Window
6 Installation of Window
7
–
PLASTERING
8 Gypsum Mixing
9 Installing the Wall Plaster
– 10 ROOF CEILING
– 11 Prefabricated Ceiling
12 Installation of Ceiling
13 PLUMBING
12
13
Table 2.1 c: Continued
GROUND FLOOR COLUMN
15 Prefabricated Pipe for Plumbing Work
Installation of pipe
17 Pipe Fitting
18 ELECTRICAL WORK
19 Prefabricated Electrical Accessory
20 Wiring Work
21 Installation of Electrical Accessory
22 PAINTING
23 Wall painting
For the structure above the ground level, the sequence of work for the
construction process just repeated the super structure work above and the sequence of
work will be repeated until the project complete.
2.4 Work Breakdown Structure (WBS)
Work breakdown structure is a process of dividing the project task into smaller
manageable components for planning purpose. A complex project is made manageable
by first breaking it down into individual component in a hierarchical structure, known as
the work breakdown structure (WBS). The WBS is the structure which defined task,
facilitating resource allocation, assignment of responsibilities and measurement and
control the project. The WBS is widely use by the project manager as a tool in the
planning activity for the construction project (Newitt, 2005).
14
The Work Breakdown Structure (WBS) is a key planning tool used to define a
project in terms of its deliverables, while providing a method for breaking down those
deliverables into meaningful work efforts. The WBS enables project managers to clearly
describe the hierarchical nature of work to be performed. The WBS also establishes a
foundation for other elements of the formal project plan. Project managers regularly are
challenged to clearly describe desired project outcomes to all involved, while they also
capture the order and sequence of the work necessary to produce those outcomes. Once
it is complete, the WBS becomes an essential building block and reference point for
other project plan components. (Newitt, 2005).
2.4.1 Use of Work Breakdown Structure (WBS)
Some companies prefer to use WBS to help identify the activities prior to
developing the schedule. This is systematic means of defining the activities so that each
activity can be readily identify by its WBS number. The WBS numbers builds
intelligence into the activity ID number. The numbering system is typically unique for a
company or project. Some prefer to divide the project by the responsible person, firm, or
subcontractor. Others divide the project or break it down according to the building or
area of work. Sometimes it makes sense to break it down according to the divisions in
the specification. A common method is to break down the project according to phases.
(Newitt, 2005).
For example with a building, start with the major phases of the project and number them
accordingly:
Phase I Project Feasibility
Phase 2 Design and Engineering