CONTRACT & ESTIMATING

Example 1

Calculate cost of brickwork (230mm wall thickness). The

price of 1 unit of brick is RM0.70 including operating and

transporting costs.Number of bricks required for 230mm brick wall thickness 118 bricks
Rm 0.70/brick(no)

Mortar required for 1m2 brickwork 0.05 m3

Cost of mortar 1:3 per m3 RM 100

Labour constant for general worker 1.2hour/ m2

Labour constant for bricklayer 2.4hour/ m2

Labour cost of general worker per hour RM3.00

Labour cost of bricklayer per hour RM4.00

Overhead cost and profit 20%
1 m3 cement 28.7 bags
Price of a bags of cement RM 16.00
Price of 1 m3 sand RM 18.00
wastage 33.3%

Mortar: Tambah air berdasarkan nisbah 1:2
simen+pasir
Kapur + pasir

1. Material Cost (MORTAR) Solution:
(mortar 1:3)
1 m3 of cement x 28.7 bags x RM 16.00 RM 459.20
3 m3 of sand x RM 18.00 RM 54.00
4 m3 material RM 513.20

33.3 % increment due to shrinkage and wastage RM 170.90
33.3 x RM 513.20 = 170.90 RM 684.10
100
Total cost of materials for 4 m3 of mortar
Rm 513.20+Rm170.90

Therefore, 1 m3 of mortar = RM 684.10 RM 171.03/m3
4 RM8.55

MORTAR cost (for 1m2 )
1m2 = 0.05 m3
=RM171.03/m3 x 0.05m3 = RM8.55

solution RM82.60
RM91.15
BRICK
=RM0.70x118 = RM82.60 RM9.60
Total material costs ( mortar + brick) RM3.60
= RM8.55 + RM82.60 = RM91.15 RM13.20

2. LABOUR COST RM104.35
Bricklayer
=2.4 hour x RM4.00/h= RM9.60

General worker
=1.2 hour x RM3.00/h= RM3.60

Total labour costs
= RM9.60+ RM3.60= RM13.20

Total costs
Material cost + labour cost
= RM91.15+ RM13.20
= RM104.35

4. Overhead cost and Profit
= 20 x RM 104.35 = Rm 20.87
100

5. Costs of 1m2 bricks
= RM 104.35 + RM 20.87
= RM 125.22

How to calculate number of brick wall 1500

Calculate:
1. Area of wall : 1500mm x 1500mm= 2250000
2. Area of 1 brick : 75(65 + 10mm) x 225(215+10mm) = 16875

No of brick = 2250000/16875 =133.33

Wastage = 5%

5/100 x 133.33 = 6.67

Total = 133.33 +6.67= 140

1500

Built Up Cost for reinforcement Work

Reinforcement work usually involves : Cutting, bending
and placing in the workplace.

Calculation should include:
1. Labour cost - skilled and labourer

2. Material cost:
* Depends on the type and size of the reinforcement
* Types
i. Mild steel-Link/stirrup (R )
ii. High Tensile Steel-main reinforcement( Y/T)
* Wastage : 5%



Reinforcement/bar

Main bar

Brc/ Wire mesh

3:00 PM stirrup

Table : Labour Constant

Num. Reinforcement Wall, Slab and Beam and Foundation
Diameter Roof column,

1 Not exceeding 10mm 6 hour 4 hour 3 ½ hour
2 10 mm to 16 mm 4 ½ hour 3 hour 2 ½ hour
3 Exceeding 16 mm 2 ½ hour 2 ¼ hour
4 hour

Hour of labour constant refer to 50kg reinforcement

Example 6

Calculate the cost of reinforcement work for a 10 mm
diameter in the foundation of the building, including
cutting,bending and placing. Calculate price of 1 kg
reinforcement work

Cost of 1 tonne ( 1000 kg ) bar reinforcement with 10 mm RM1850.00
diameter

Labour cost of skilled worker per day RM 40.00
Labour cost of general worker per day RM 25.00
Labour constant for cutting and bending of 50kg 2 1/2 jam
Labour constant for remove and placing of 50kg 2 1/2 jam
Overhead cost and profit
Wastage 20%
5%

solution RM1850.00
RM92.50
1. Material costs(50kg) RM 4.63
1 tonne ( 1000 kg ) bar reinforcement
RM 97.13
Therefore 50kg
1850x50= RM92.50
1000

5% increment due to wastage
5/100 x 92.50 = RM4.63

Total material costs
= RM92.50+RM4.63 = RM 97.13

Costs of 50kg of reinforcement

2. Labour costs RM 5.00
Labour cost of skilled worker per hour
RM 40.00 =RM 5.00 RM 3.13
RM12.50
8 RM7.83
Labour cost of general worker per hour RM 20.33
RM 25.00= RM 3.13

8
Skilled worker
2.5 hour x RM5.00= RM12.50

General worker
2.5 hour x RM3.13= RM7.83

Total labour costs of 50kg
= RM 12.50+ RM 7.83= RM 20.33

3. Total costs RM 117.46
= Material cost + Labour cost RM 2.35
= RM 97.13 + RM 20.33 = RM 117.46 RM 0.47
= RM 2.82
Total costs of 1kg
= RM 117.46/50= RM 2.35

4. Overhead cost and profit 20%

= 20 x RM 2.35 = RM 0.47
100

Total costs of 1kg reinforcement work
= RM 2.35+ RM 0.47 = RM 2.82

EXERCISE

Exercise 1

Calculate cost of brickwork ,given price of 1 unit of brick is RM0.65 including
operating and transporting costs.

Area of wall 2000 mm x 2000mm

Mortar required for 1m2 brickwork 0.06 m3

Cost of mortar 1:3 for 1 m3 RM 100

Labour constant for general worker 1.2hour/ m2

Labour constant for bricklayer 2.4hour/ m2

Labour cost of general worker per hour RM5.00

Labour cost of bricklayer per hour RM6.00
Overhead cost and profit 15%
wastage 5%

Answer:

How to calculate number of brick 2000
wall
Calculate:
1. Area of wall : 2000mm x 2000mm= 4 000 000 2000
2. Area of 1 brick : 75 x 225 = 16875

65 + 10mm 215+10mm

No of brick = 4 000 000/16875 =237.04

Wastage = 5%

5/100 x 237.04 = 11.85

Total = 237.04 +11.85= 248.89 === 249

Exercise 2

Calculate the price rates of 1 kg reinforcement works by using the data given.

Reinforcement (R10)/ tonne RM 2850.00
Skilled labour/day RM 65.00
Labour /day RM 35.00
Cutting and bending 50 kg bar 2.15 hour
Lifting and fixing 50kg bar 2.10 hour
Wastage 5%
1 day 8 hour
Overhead cost and profit 20% (klu xde assume)

Exercise 3

Based on the data below, build up cost 1m3 concrete of ground beam work manually. Mixing, transporting,
casting and compacting into the formwok.

Berdasarkan data di bawah, kirakan bina kadar 1m3 kerja konkrit bagi rasuk tanah secara manual. Menggaul,
mengangkut, menuang dan memadatkan ke dalam kotak bentuk.

Concrete ratio/nisbah simen: 1:2:4-20mm aggregate
1 m3 cement/1 m3 simen: 28.7 bags/28.7 beg
Price of a bags of cement/harga 1 beg simen: RM 17.50
Price of 1 m3 sand/ harga 1 m3 pasir:
Price of 1 m3 coarse aggregate/harga 1m batu baur kasar: RM 25.00
RM 35.00

Labour cost/kos buruh: RM 40/day

Labour/ buruh: 1 person

Increse in volume due to shrinkage,wastage and compaction/ peningkatan 50%
isipadu terhadap pengecutan ,pembaziran dan pemadatan konkrit:

Labour constant: mixing, transport, casting and compacting per day/ 7.75h/m3
menggaul,mengangkut,menuang dan memadatkan per hari:

Original price of machine/ Harga asal mesin: RM 20 500.00
Diesel: RM 1.93/liter@ 20 liter/day
Lubricant/Pelincir: RM 6.50/liter@ 4 liter/day

Overhead cost & profit/ pengurusan& keuntungan: 18%

Manually

1. Material cost
2. Labour cost
3. Total cost(material + labour)
4. Overhead cost
5. Cost for 1m3

Machine

1. Material cost
2. Capital cost(purchase) / rental cost(Hire)
3. Operating cost-labour cost
4. Oil cost
5. Daily machinery cost( labour+fuel+capital cost)
6. Production cost
7. Overhead cost
8. Cost for 1m3

Exercise 4

Based on the data below, calculate the build up rate of 1m3 concrete work using machinery mixer
Berdasarkan data di bawah, kirakan bina kadar 1m3 konkrit menggunakan mesin pembancuh
Assume wastage: 50%

Concrete ratio/nisbah simen: 1:3:6-20mm aggregate
1 m3 cement/1 m3 simen: 28.7 bags/28.7 beg
Price of a bags of cement/harga 1 beg simen: RM 18.00
Price of 1 m3 sand/ harga 1 m3 pasir: RM 20.50
Price of 1 m3 coarse aggregate/harga 1m batu baur kasar: RM 35.80

Original price of machine/ Harga mesin: RM 20500.00
Investment returns of capital at a rate / kadar pulangan pelaburan: 12% per annual for 5 years.

Repairing cost for 5 years/ kos membaiki selama 5 tahun: 10%

Transportation costs for 5 years/ kos pengangkutan selama 5 tahun: 8%

Machine working / Penggunaan mesin: 290 days a year/ 290 hari setahun

Rate of machine capability/keupayaan menggaul: 3.5m3/hr

Labour cost/kos buruh: RM 30/day
Operator/Operator : 1 person
Labour/ buruh: 4 person
Diesel: RM 1.93/liter @ 20liter/day
Lubricant/Pelincir: RM 6.50/liter@ 4liter/day
Overhead cost & profit/ pengurusan& keuntungan: 17%

CHAPTER 7(1) :
THE QUANTITY MEASUREMENT

Quantity Bills of quantity
measurement
is a document which contains
- Taking off quantities item list of building item and its

Find the uses of quantity.
bill of

quantity?

Taking off

1. Earthwork(site clearance, cut & fill)
2. Piling work
3. Sub structure

- pad foundation
- column stump
- ground beam
- ground floor
4. Super structure ( column,upper floor….)
5. Finishing work( floor,wall,ceiling)

Bill of Quantity

- Bill of Quantity is a document which contains list
of building item and its quantity.

- Bill of Quantity is prepared based on standard
principles.

- To produce the Bill of Quantities, a detailed
quantity survey or materials take off has to be
completed.

- The services are provided by a professional
Quantity Surveyor (QS).

- The Bills of Quantities are usually indicated by
items of work, units of measurement, how many
Units, quantities of work, rate for doing the work,
and total value of the work.

Uses

- To provide sufficient information on the quantities of
Works to be performed to enable bids to be prepared
efficiently and accurately.

- To provide a priced Bill of Quantities for use.

i. To prepare progress payments
ii. To evaluate non compliance work
iii. To order and purchase materials
iv. To call for tender

Bill of Quantity

Rate Total
RM Sen
No. Description of item Unit Quantity RM Sen

3.0 SITE CLEARANCE

3.1 Site clearance approximately 1.0 m

wide from outside and inside fencing

line including shrubs and trees less

than 600 mm girth as directed

including grubbing of roots and

remove to contractors own dumping

ground. M 4 500 1 50 6750 00

Bill of Quantity

Rate Total amount
RM Sen
No. Description of item Unit Quantity RM Sen

1 Element 1: work below lowest floor finish

Generally

All excavation are measured from

formation level unless otherwise stated

Surface excavation

Excavate oversite to reduce level; maximum

depth not exceeding 1.00m depth, get out

and cart away from site including level and

grading to surface of exacvation

hardcore M3 200

200mm under raft foundation M2 350
Lean concrete

50mm thick under raft foundation

M3 18



UNITS IN QUANTITY MEASUREMENT

In the preparation the bill of quantity, a standard method of measurement
is used. For every quantity measurement there is standard unit applicable.

Measurement Units

Length Linear metre (m)

Area Square metre (m2)

Volume cubic metre (m3)

Weight Kilogramme / tonne

Number No

Item Removing Item Mobilization of
tree piling plant

Slip sort form/taking off form - Piling
- Work below lower floor
DRWG NO. BILL ELEMENT - brick
HEADING
DESCRIPTION NO. SLIP NO

- Jointing pile UNIT
- Excavation QUANTITY
- Column
- beam
- Internall wall

TIMESING COLUMN
DIMENSIONING
COLUMN

SQUARING COLUMN
DESCRIPTION
COLUMN

TIMESING

DIMESIONING
SQUARING
example

21

DESCRIPTION COLUMN

TIMESING COLUMN (COL 1)
 The ( / ) means times
 Dotting ( . ) is a quantity surveying term which means

adding

DIMENSIONING COLUMN (COL 2)
 Dimensions (length, width and height or depth).
 Dimension are always given in meters and to 2 decimal

points

SQUARING COLUMN COLUMN (COL 3)
- answer

DESCRIPTION COLUMN (COL 4)

 The description of the items measured.
 The description should contain information required to

enable the contractor to price for the items.
 A bracket – using bracket for a set of dimension.
 Ditto - is a quantity surveying term which as means “as

above”
 a.b.d. as before describe

structural drawing,

• Consist of all the drawings that describe the structural members
of the building:

Foundation plans and details, framing plans and details, wall
sections, column and beam details, and other plans, sections,
details, and schedules necessary to describe the structural
components of the building or structure.

example

example

example



Footing layout
Typical pad footing detail

Pad Footing schedule

Column schedule

Ground floor beam layout

Ground beam detail

Ground floor slab layout

estimate

Earthwork

- Estimate earthwork (site clearing, remove unsuitable
material, cut & fill)

Substructure

Produce taking off quantities:
- Piling work(concrete pile, timber pile,steel pile)
- Work below lowest level( concrete, formwork, and

reinforcement)
i. Foundation
ii. Column stump
iii. Ground beam
iv. Ground slab





Ground beam

Foundation &column stump