This document describes a line of balance (LOB) planning example for constructing 40 similar houses. It provides the man-hours and crew sizes needed for each activity of foundations, brickwork/plastering, and roofing. Using this information, the document generates a LOB chart showing the start and finish dates for each activity on each unit over time. Based on the LOB chart, it determines that after 50 days of construction, foundations would be complete on 33 units, brickwork on 25 units, and roofing on 18 units. The total planned completion time of 71.93 days is less than the required 15 weeks, showing the project will meet its deadline.

1. MANAGEMENT:CIVIL II_ MCIV 2/0
MODULE FIVE(5): LINE OF BALANCE(LOB) PLANNING
JB NARTEY

2. LINE OF BALANCE(LOB)
• In construction there are some projects in which a predominant feature is
that of repetition.
• The following are typical examples:
• Housing contract
• VIP Toilets
• Piling contract
• Capping piles
• A block of flats
• A hotel with a series of identical rooms
• etc.
• For such work it is extravagant, as well as difficult, to draw and maintain
critical path networks illustrating the detail of the construction process for
each of the units involved.
•

3. LOB REQUIREMENTS
• A required delivery programme/Rate of
delivery for completed units.
• Contract Period
• The dependency and relationship of work
activities .
• Labour input per section of the unit

4. EXAMPLE
LOB TUTORIALS
Your company has been appointment for construction of 40 similar RDP houses in East London
rural areas. Details of the contract are as follows:
 You are required to deliver the houses at a rate of 4 units/ week.
 Total project period not to exceed 15 weeks.
 You plan to work a 5 day week.
 You plan to work 8hrs per day.
The table below illustrate the information after you have done the calculations.
Operation Man-hours/unit Gang/Team Size
Foundations 240 3
Brickwork/plastering 160 6
Roof 75 5
You are required to do the following:
(a) Draw the LOB chart graph. Allow a 4-day buffer period between activities.
(b) Use the information provided to determine the number of units expected to be started
and completed after 50 days of construction.
(c) Does the project meet the specified duration for completion? Provide explanation to
support your answer.
(d) How many planned days does it take to complete the project?

5. FOUNDATIONS
Solution;
a) Foundations;
Duration = Man-hours/unit/ [Gang Size/unit x hrs/day] = 240/3x8 = 10 days
No. of Gangs needed(theoretical) = Desired prod rate x man-hours/unit/[gang
size/unit x hrs/dayxdays/week] =4 x240/3x8x5 = 8 gangs
No. of Gangs needed(Actual) = 8 gangs
Start of foundations on unit 1= day 0
Finish of foundations on unit 1= day 10
Start of foundations on unit 40 = 0 +(40-1)x10/8 = day 48.75
Finish of foundations on unit 40= day 58.75
Rate of Construction = Desired prod rate x Actual No.of gangs/Theoretical No.of
gangs= 4x8/8 = 4 units per week.
Checks: Rate of Construction = 40 units/ (58.75/5) = 3.75 units per week approx 4
units per week.
Keep the rate of construction as uniform/balanced as possible between the activities
and close to 4 units per week
58.75 days( 11.75 weeks)
0 10
Foundunit1
10 days
48.45 58.75
Found unit 40
10 days

6. BRICKWORK/PLASTERING
Brick work/Plastering;
Duration =Man-hours/unit/ [Gang Size/unit x hrs/day] = 160/6x8 = 3.33 days
No. of Gangs needed(theoretical) =
Desired prod rate x man-hours/unit/[gang size/unit x hrs/dayxdays/week] = 4
x160/6x8x5 = 2.67 gangs
No. of Gangs needed(Actual) = 3 gangs
Start of brickwork/plastering on unit 40= 58.75 + 4 = day 62.75 ( 4 days buffer)
Finish of brickwork/plastering on unit 40 = 62.75+3.33 = day 66.08
Start of brickwork/plastering on unit 1= 62.75-(40-1)x 3.33/3 = day 19.46
Finish of brickwork/plastering on unit 1= 19.46+3.33 = day 22.79
Rate of Construction = Desired prod rate x Actual No.of gangs/Theoretical No.of
gangs =4x3/2.67 = 4.49 units per week> 4 units/week
46.62 days( 9.32 weeks)
Checks; Rate of Construction = 40 units/9.32 weeks =4.2 units per week>4
units/week,ok
Keep the rate of construction as uniform/balanced as possible between the activities
and close to 4 units per week
19.46 22.79
Brickwork/plasteringunit1
3.33 days
58.75+4/62.75 66.08
Brickwork/plastering unit 40
3.33 days

7. ROOFING
Roofing;
Duration = Man-hours/unit/ [Gang Size/unit x hrs/day] =75/5x8 = 1.87 days
No. of Gangs needed(theoretical) = Desired prod rate x man-hours/unit/[gang
size/unit x hrs/dayxdays/week] =4 x75/5x8x5 = 1.5 gangs
No. of Gangs needed(Actual) = 2 gangs
Start of roofing on unit 40= 66.08+4 = day 70.06 ( 4 days buffer)
Finish of brickwork/plastering on unit 40 = 70.06+1.87 = day 71.93
Start of roofing on unit 1= 70.06-(40-1)x 1.87/2 = day 33.60
Finish of roofing on unit 1= 33.60+1.87 = day 35.47
Rate of Construction = Desired prod rate x Actual No.of gangs/Theoretical No.of
gangs =4x2/1.5 = 5.33 units per week> 4 units/week
Checks: Rate of Construction = 40 units/7.67 weeks = 5.2 units per week>4 units per
week,ok
38.33 days( 7.67 weeks)
Keep the rate of construction as uniform/balanced as possible between the activities
and close to 4 units per week
33.60 35.47
Roofingunit1
1.87 days
66.08+4/70.06 71.93
Roofing unit 40
1.87 days

8. LOB Diagram/chart
4 days buffer 4 days buffer
10 20 30 40 50 60 70 80
40
39
38
37
36
35
34
33
32
Units 31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7 Time of Completion
6
5
4
3
2
1
0 10 20 30 40 50 60 70 80
Duration(days)
Time of measuring progress
Foundations
Brickwork/Plastering
Roofing

9. CONCLUSIONS
• Refer to LOB Chart/Graph;
• After 50 days of construction;
• Foundations are expected to be completed on 33 units
• Brickwork/plastering is expected to be completed on 25
units
• Roofing is expected to be completed on 18 units.
•
• Refer to LOB Chart/Graph;
• Expected period of completion ; 71.93 days = 14.3
weeks< 15 weeks
•