CONTRACT & ESTIMATING

Flat roof

 Roof with less than 10 0 pitch is categorized as flat roof
 Two types of flat roof which is :
1. Fully flat roof
2. Flat roof with parapet walls

Parapet wall



Concept of height FLAT ROOF

FULLY FLAT ROOF

T= 0.6m

Building height = H + 0.6m
H

T= Height of parapet wall
Building height = H+ T

H

If parapet wall < 600mm
❖Height = H + 0.6 m

If parapet wall > 600mm
❖Height = H + T(parapet height)

PITCHED ROOF

PITCHED ROOF

Roof with more than 10 0 pitch is categorized as pitched roof

FORMULA
Building height= H + T/2

Roof height = T

H

Ground
level

Example 1

Refer to the data below, calculate the cost of the building using the
Cubic Content Method. Assume cost rates as RM100.00/ m3

Building Length, L = 45.00 m

Building Width, W = 15.00 m

Building Height, H = 20.00 m

Solution:

Building Volume = LxWxH
= = 45.00 x 15.00 x 20.00
13, 500 m3

Building Cost = Building Volume x price rate / meter
= 13, 500 m3 x RM 100.00 /m3
= RM 1,350,000.00

Example 2

Refer to the figure, calculate the Rear view
cost of the building using the
Cubic Content Method.
Assume cost rates as RM350.00/
m3

1500

Plan view

solution 9.5-6.5-2.5= 0.5
0.5 +6.5 = 7m
Flat roof volume area
= 7.00 x 4.50 x (9.5 + 0.60)
=7.00 x 4.50 x 10.10
=318.15 m3

Pitch roof volume area
=4.00 x 1.50 x (7.00 + 2.50/2)
=4.00 x 1.50 x 8.25
=49.00 m3

Building Cost =(318.15 + 49.00) x RM 350.00
=367.65 x RM 350.00
=RM 128, 677. 50

EXERCISE

Exercise 1

Calculate the cost of new school building which
accommodate 4000 students. Given the factor of
cost increment is 15%.

Type Construction Costs (RM) Number of
students
School A 4,000,000.00
1500
School B 5,000,000.00
2100
School C 6,500,000.00
2800

Exercise 2

Base on diagram below, calculate the cost of the
building, assume cost rate as Rm 350/m2

18 m garaj
ANSWER: RM 52500
Room 2 Room 1

10 m

Area 3

12 m

Exercise 3 600
7500
Base on diagram below, calculate the cost of the building, assume cost rate as Rm 300/m3

800

8600

REAR VIEW
20 m

wc Room 2 wc
Room 3
13 m
Area 2

Room 1 Area 1

15 m

PLAN VIEW

ANSWER: RM 688350.00

Exercise 4

A= RM 1932.22 B= RM 3 956 470.00

ANSWER: RM 50 352.00

Section A Final exam question

1. List four types of engineering work in construction industry

2. Name four types of head system based on the scope of work in construction

3. List and briefly explain three main catergories of contractors

4. List four importance of organization chart in contractor firm

5. State two duties of Contractor Service Centre

6. Identify two diferences between Domectic and nominated sub-contractor

7. Explian two activities related to construction

8. State two types of work which are involved in the construction industry

9. State two roles of CIDB

10.Complete the table below regarding Garade and Tendering capasity by CIDB

grade Tendering capasity

G1 RM

Section B
1. Explian the role of each member of builder team as listed below
i. Contractors
ii. Architects
iii. Civiland Structural Engineer/electrical and Mechanical Engineer
iv.Quantity Surveyor
2. Explian seven activities involved in construction
3. Explian the role of CIDB
4. Identify the roles of each member in design team and builder team members.
5. Describe the relationship between consturction industry and economic growth.

CHAPTER 6 :
BUIL-UP RATE METHOD

What is rate

Price per unit of measurement
Example:
Price rate for 1 m3

RM 4.14/ m3 unit of
measurement

It is the list of rates of various items
of work.

The schedule is prepared by the
Public Work Department / JKR.

The purposes Of The Built-Up Rate Methods

 Know the financial allocation employer.
 Know the suitability design based on limit

allocation.
 As information and record for reference and

estimate projects for the future.

Types of built up work

1. Excavation work(manual & machine)
2. Concreting work(manual & machine)
3. Brick work
4. Reinforcement work

Types Of Cost
Material cost
Labour cost
Plant and equipment costs
Overhead cost and Profit

1.0 Material Cost

- Material cost such a brick, roof, tile, glass, iron, cement
and sand.

- Estimated price depends on:

i. The original cost of the material
ii. Transportation cost
iii. Storage cost
iv. Wastage cost

2.0 Labour Cost

Labour cost is a fee or wages to the workers after
work has been completed. In the construction
industry, workers are divided into two classes:
i. Skilled worker
 Workers who are skilled in their own field such as bar

bender, carpenter and bricklayer.
ii. General worker
 Workers who carry out general work such as transporting

dumping and clearing of site.

Types of labour

 Craftsman
Carpenter, blacksmith, bricklayer, craftsman plaster,
plumber and others

 Semi-skilled Labour
Craftsman’s assistant

 Labourer
Craftsman or semi-skilled labour assistant

 Head
Somebody which lead a group of craftsman, semi-
skilled labour and labourer.

3.0 Plant and equipment costs

Contractor can purchase or hire plant and equipment as
follows;

i. Non-machinery plant and equipment such as scaffolding,
ladder, wheelbarrow, pails and others.

ii. Machinery plant and equipment such as lorry, bulldozer,
concrete mixer, concrete vibrator equipment and others.

4.0 Overhead/operating cost and profit

Overhead cost and profit:
Percentage of materials, labour, plant and equipment
costs and others.

Include management/operation cost:
 Electricity, water and telephone bills related to office and

workshop operations.
 Cost of office and workshop furniture and purchase of

stationery.
 Allowances for company’s board of directors.
 Salary of management personnel
 SOCSO
 office rental and others.

1) Built Up Cost for Excavation Work

They are two ways of conducting excavation work ;

i. Manual excavation work

- Using hand equipments such as hoe and shove.
- Suitable for small work and limited working area.

ii. Excavation work using machinery

- Using machineries such as tractor, bulldozer, backhoe
and excavator.

- Suitable for large excavation work.

Calculation should include:

 Excavation
 Transporting and dumping of the excavated soil
 Backfilling and compacting
 Constructing temporary trench support on the

sides of excavated trench if necessary.
 excavation Unit : m3 (>100mm)

m2 for topsoil (<100mm)

Table 1: Increasing volume

types Increase (%)
Sand 10
Clay 20
Natural soil 25
gravel 50

Table 2: labour constant/Angkatap Buruh

Example 1

Excavation by hand

Example:

Built up cost for manual excavation work, as follows:

Manual excavation of ditch, not exceeding 1.5 meter deep
and dumping to an average distance 100m from the site.

Important information :

- Excavating trench/ditch not exceeding 1.5m deep : 1.74hour/m₃(refer table 2)

- Dumping of soil 100m away from site. : 1.00 hour/m₃(refer table 2)

- Increased volume of soil after excavation : 25% (refer table 1)

- Overhead cost and profit. :10%

- Labour cost for excavating and dumping trench/ditch per day (8 hours) : RM 40

(refer price rate-jkr)

1. Labour Cost solution

- Excavating trench not exceeding 1.5m deep :1.74 hour /m₃
:1.00 hour/m₃
- Dumping of soil 100m away from site. :25%
:0.25 hour /m₃
- Increased volume of soil after excavation
2.99 hour /m₃
= 25 x 1.00 hour /m₃

100

Total labour constant

1.74+1.00+0.25 =2.99

Labour rates for excavate, remove and disposal of 1 m₃ : RM 14.95

2.99 hour x RM40 = RM 14.95/hour RM 1.50
------------
8 RM 16.45
=========
2. Overhead cost and profit ( 10 % )
= 10 x 14.95=1.50
100

Total excavation cost for trench for every 1 m₃

Excavation By Machine ( rental)… (1 m3 )

Calculate in 1 m3 excavation work, starting from ground
level more than 1.50m but not exceeding 3.00m depth.
Important information :

- Rental rate RM 50.00/ hour
- Machine operator 1 person
- Labour 1 person
- Machine operator cost RM 4.00/hour
- Labour cost RM 2.50/hour
- Diesel consumed 4.55 liter/hour
- Lubricant oil consumed 0.24 liter/hour
- Cost of Diesel RM 2.05/liter
- Cost of lubricant oil RM 25/ liter
- Production capability 19.11 m3 /hour
- Overhead cost and profit. 10%

Excavation By Machine = 1 person x RM 4.00 Example 2
= 1 person x RM 2.50
Solution: RM 50.00

1. Machinery cost RM 4.00
RM 2.50
Rental rate per hour RM 6.50

2. Labour Cost RM 9.33
RM 6.00
Machine operator ( 1 person ) RM 15.33
Laborers

3. Oil cost = 4.55 liter x RM 2.05
= 0.24 liter x RM 25
Diesel
Lubricant oil

solution

Total machinery cost per hour = Machinery cost + Labour cost + Oil cost
= RM 50.00 + RM 6.50 + RM 15.33
= RM 71.83/hour

4. Production capability

Production capability 19.11 m3/hour
Machinery costs for 19.11m3 soil :

19.11 m3 /hour = RM 71.83/hour

1 m3 =RM 71.83 x 1 hour = RM 3.76/ m3
hour 19.11 m3

Excavation costs for 1 m3 = RM 3.76

5. Overhead cost and profit ( 10%) RM0.38
= 10 x 3.76

100

6. Price rate for 1 m3 RM 4.14/ m3

RM 3.76 + RM0.38

EXERCISE

Calculate in 1 m3 excavation work, starting from ground level more than
1.50m but not exceeding 3.00m depth.
Important information :

- Rental rate RM 20.00/ hour
- Machine operator 1 person
- Labour 1 person
- Machine operator cost RM 4.00/hour
- Labour cost RM 2.50/hour
- Diesel consumed 4.55 liter/hour
- Lubricant oil consumed 0.24 liter/hour
- Cost of Diesel RM 2.05/liter
- Cost of lubricant oil RM 25/ liter
- Production capability 12.30 m3 /hour
- Overhead cost and profit. 10%

3:00 PM

Excavation debris, throw from site at average distance of 50.00m from excavation site. Example 3

1. Machinery costs RM 20.00
Rental rate per hour
RM 4.00
2. Labour costs = 3.41 liter x RM 0.70 RM 2.39
Machine operator ( 1 person ) = 0.11liter x RM 3.60 RM 0.40
= 1 person x RM 4.00 RM 2.79

3. Oil costs
Diesel
Lubricant oil

Total machinery cost per hour
= Machinery cost + Labour cost + Oil cost
= RM 20.00 + RM 4.00 + RM 2.79
= RM 26.79/ hour

4. Production capability Solution
Production capability 12.30 m3/hour
Machinery costs for 12.30m3/hour = RM 26.79/hour = RM 2.18/m3

= RM 26.79 x 1hour
12.30 m3

Excavation costs for 1 m3

5. Overhead cost and profit ( 10%) = RM 0.22
= 10 x 2.18 = RM 2.40/ m3

100

6. Price rate for 1 m3
RM 2.18 + RM 0.22

Built Up Cost for Concreting Work

Two ways of mixing :

1. Manual concreting work
- Using light equipment such as hoe, shovel and pail.
- Suitable for small quantity.

2. Mixing concrete using machinery
- Using special machine.
- Suitable for large scale work.

Calculation should include

Material Price
- Cement
- Sand
- Aggregate.

Shrinkage and Wastage
- Shrinkage : volume change.
- The volume of concrete reduces when the concrete

mixes with water.
- Most of the concrete will waste during mixing,

removing and pouring concrete.
- 50 % increment due to shrinkage

3:00 PM

Manual Concreting Work ( 1m3) Example 1

Built up cost of mixing concrete manually, as follows:
“Solid concrete (1:2:4-aggregates 20mm) for ground beam;
transport and cast into the formwork”. (unit m3)

Important information:

1 m3 cement 28.7 bags
Price of a bags of cement RM 10.00

Price of 1 m3 sand RM 15.00

Price of 1 m3 coarse aggregate 28.7 bags RM 25.00

Increase in volume due to shrinkage, wastage and compaction of concrete 50 %

Overhead cost and profit 20%
RM 40.00
Labour cost for 1 worker per day (8 hours) RM 40.00 7.75 hour/m3

Labour costant for mixing, transporting, casting and 7.75 hour/m3
compacting concrete into formwork per day (8 hours)

1. Material Cost RM 287.00
1 m3 of cement x 28.7 bags x RM 10.00 RM 30.00
2 m3 of sand x RM 15.00 RM 100.00
4 m3 of coarse aggregate x RM 25.00

7 m3 concrete material RM 417.00

50 % increment due to shrinkage, wastage and compaction

50 x RM 417.00 = 208.50 RM 208.50

100

Total cost of materials for 7 m3 of concrete RM 625.50

417.00+208.50

therefore, 1 m3 of concrete = RM 625.50 RM 89.36/ m3

7

2. Labour Cost

Labour costant for mixing, transporting, casting and 7.75 hour/ m3
RM 38.75 / m3
compacting 1 m3 of concrete
RM128.11/ m3
= 7.75 hour/ m3 x RM 40.00 =38.75

8 hours

3. Total Cost

Total material cost + labour cost

RM89.36 + RM38.75= RM128.11

4. Overhead cost and profit

= 20 x RM128.11
100

= RM 25.62/ m3

5. Manual cost rate for concreting work per 1 m3 RM153.73/ m3
RM128.11 + RM25.62= RM153.73/ m3

Example 4

Mixing Concrete Using Machinery (beli jentera)

Built up cost of mixing concrete using concrete mixer
, as follows: “Mass concrete (1:2:4-aggregates 19mm)”.
(unit m3)
Material cost refer to example 1 = RM 89.36/ m3

3:00 PM

Example 4

Price of concrete mixer RM6000.00
3.44 m3/hour
Production capability of concrete mixer 1/20 of the original
price
Rates of transport machinery to the construction site for 5 10 %
years 10 %
150
Bank interest costs a year 3.41 litre/hour
0.50 litre/day
Cost of repairing machines for 5 years 1 person
4 person
The number of days using the machine for a year 10 %
8 h/day
Diesel consumed per hour 1 h/day
RM1.04/litre
Lubricant oil consumed per day RM5.00/litre
RM2.00/hour
Operator needs

Assistants needs

Overhead cost and profit

Working period

Duration of cleaning and maintenance machines

Cost of diesel

Cost of lubricant oil

Labour cost per hour

Solution:

1. Material cost RM 89.36/ m3
RM 6000.00
2. Capital cost
Price of concrete mixer RM 3000.00
Interest on capital
= 10 x 5 year x RM 6000 RM 300.00
RM 9900.00
100
= RM 3000.00 RM 1980.00
Repairing machines cost RM 13.20
= 10 x RM 6000 = RM600
RM 600.00
100
Transport costs
= 1 x RM 6000 = RM 300.00

20

Total capital cost for 5 year

Rm 6000+Rm3000+Rm600+ Rm 300 = RM 9900

Total capital cost per year
=RM 9900.00/5 = RM 1980.00

Total capital cost per day
=RM1980.00/150= RM 13.20

3. OPERATING COST 8 + 1(maintenance)

Labour cost

Labour operator (1 person)

= 1 person x 9 hour x RM 2.00= RM 18.00 RM 18.00
RM 64.00
Labour assistant rm 28.37
= 4 person x 8 hour x RM 2.00= RM 64.00 rm 2.50
Rm 112.87
4. FUEL
Diesel Rm 126.07/day
3.41L x Rm1.04x 8= Rm 28.37
Lubricant
0.5L x Rm5.00= Rm2.50

5. Daily operating cost
Rm18.00+Rm64.00+Rm28.37+Rm2.50
= Rm 112.87

6. Daily Machine Cost
=Capital cost + Operating Cost
=Rm13.20 + Rm 112.87
=Rm 126.07

7. PRODUCTION COST 27.52 m3
Production capability (3.44 m3/hour)
Daily production capability (8hour) RM 4.58
= 3.44m3/h x 8 hour/1 d = 27.52 m3 / day
Mixing costs for 27.52 m3 /d concrete= RM 126.07/d RM 93.94
1 m3 = RM 126.07 = Rm 4.58 Rm 9.39
Rm 103.33/m3
27.52 m3
Mixing costs for 1 m3 concrete = RM 4.58

Total mixing cost for 1 m3 concrete
=Material Cost + mixing cost for 1 m3
=RM 89.36/ m3 + RM 4.58 /m3
= RM 93.94 /m3
8. Overhead cost and profit
= 10 x RM 93.94 = Rm 9.39

100
9. Cost 1 m3 concrete
Mixing cost for 1 m3 concrete
=RM 93.94 + RM 9.39 = Rm 103.33

Built Up Cost for Brick Work

- Brickwork is calculated based on square metre(m2) .
- The unit price per square metre of brickwork is

calculated based on the following:

 Materials: brick and mortar
 Labour costs
 Overhead cost and profit

Brick size

102.5