Estimating presentation (final)

S E M I N A R
GROUP MEMBERS
BENJAMIN NG KIEN FUNG
GOH PEI JENG
LAI EUGENE
MELVIN TAN TENG HUNG
TANG LAM YU
YAP CHOE HOONG
0324541
0329735
0324075
0324938
0324966
0323161
BENJAMIN NG 0324541 | GOH PEI JENG 0329735 | LAI EUGENE 0324075 | MELVIN TAN 0324938 | TANG LAM YU 0324966 | YAP CHOE HOONG 0323161

QUESTION 5
You are currently working as a trainee at Taylor’s QS consultant. You are required
to provide an estimate for a medium cost housing development in Petaling Jaya
based on a set of preliminary sketch drawings. You are given a day to complete the
task.
a) Explain the various methods of estimating. (15 marks)
b) Select the appropriate methods of estimating that you will apply for the task
and justify your selection. (10 marks)

METHOD OF ESTIMATING
SINGLE RATE
UNIT METHOD SQUARE METRE
METHOD
CUBIC METRE
METHOD

UNIT METHOD
• cost per car space
HOSPITALS
• cost per pupil place
Multiplying the number of
accommodation for a new building
with the cost per unit of
accommodation based on a suitable
building.
standard
units of
accommodation
x cost / unit
• calculating from sketch design
• information from client
• project design estimates
• bid estimates
• cost per car space
SCHOOLCAR PARKS
CURRENT UNIT OF ACCOMMODATION
OBTAINED BY
USED FOR

ADVANTAGES OF UNIT METHOD
can be done quickly where a
ballpark figure is required instantly
no take-off or measurements
needed
useful for buildings where
standard-sized units occupy most of
the space
no consultant charge
estimate can be done even if there
are no drawings or specifications

DISADVANTAGES OF UNIT METHOD
not a reliable method not based on drawings or
specification
large deviation from the accurate
value

SQUARE METRE METHOD
Internal gross floor area obtained by
• within external area
• without adjustments for partition walls,
staircases or lifts
Measuring internal gross floor area
of a building and multiplying by
the cost per m2.
internal gross
floor area
x cost / m2
• first sketch designs produced by architect
• building project from a low-income house
to a large commercial project
INTERNAL GROSS FLOOR
OBTAINED BY
USED FOR

ADVANTAGES OF SQUARE METRE METHOD
reliable on architect’s sketch
drawing & building plan
faster to produce than a Bill of
Quantities
current building index can
incorporated in the estimate
estimates are based on past similar
project

DISADVANTAGES OF SQUARE METRE METHOD
does not take into account the
aerial configuration of the
buildings
does not take into account total
perimeter of the wall
does not take into account floor-to-
ceiling height
does not take into account area
and type of wall finishes

CUBIC METRE METHOD
• within external area
• height of the building is taken from top of
foundation to roof
Measuring cubic content and
multiplying rate per cubic metre
Volume x cost / m3
• building project
• to overcome the current criticism floor area
method that does not take possible
variations of the storey height.
VOLUME OF SUBJECT
OBTAINED BY
USED FOR

ADVANTAGES OF CUBIC METRE METHOD
simple math process and easy to
understand
quick method
satisfactory on works of a recurring
nature
suitable where cubic content of a
space or building directly influence
cost of an element

DISADVANTAGES OF CUBIC METRE METHOD
required higher levels of skill to
access unit rate
difficult to adjust unit cost due to
large number of variables
does not provide indication about
amount of usable space
fail to take variations in plan,
shape, height

METHOD OF ESTIMATING
DETAILED ESTIMATING
APPROXIMATE
QUANTITIES
METHOD
ELEMENTAL
METHOD
COMPARATIVE
METHOD

APPROXIMATE QUANTITIES METHOD
Based on measurement groups where Bill Items with the same unit
group together by using Group Unit of Measurement.
INTRODUCTION
More accurate & reliable
More flexible
Require sketch plan/preliminary working
drawing before calculating
REQUIREMENT

WHEN USE APPROXIMATE QUANTITIES METHOD
• Cost planning purposes when full drawings and
specification are prepared
• Prepare accurate multiple rate estimates
• Measuring extensive renovations and refurbishments
• Estimator can use for tendering or
negotiating with the client

ADVANTAGES OF APPROXIMATE QUANTITIES METHOD
Faster than a normal Bills of
Quantities
Reliable estimate for major
renovations and refurbishment
Accurate based on advanced
drawings

DISADVANTAGES OF APPROXIMATE QUANTITIES METHOD
Composite rate build-up takes a lot
of the Quantity Surveyor’s time
Percentage addition for sundries is
hard as it cannot be measured

ELEMENTAL QUANTITIES METHOD
IMPORTANCE
• a budget setting technique which considers the major elements of a building
• elemental method can also be used to develop an initial cost model
• the sum of the cost targets for group elements
• measure quantities and produce the project cost much faster than
detailed Bills of Quantities.

WHEN USE ELEMENTAL QUANTITIES METHOD
• best used for comparing design alternatives.
• suitable for securing finance or presentation purposes
• Quantity Surveyor can keep a check on costs.

ADVANTAGES OF ELEMENTAL QUANTITIES METHOD
cost are easily identified and
can be adjusted as required.
This estimate is good for cost planning
able to check the elemental costs
throughout the design stage.
estimate much more closer to the tender value
than the superficial area method.

DISADVANTAGES OF ELEMENTAL QUANTITIES METHOD
Plan adjustments and constant cost
checking in the preliminary stage.
• More work is needed in adjusting the Item
Elemental Rate Build Up for BOQ linking.
• The Architect and QS involved in the
preliminary stage need to be well versed with
the cost implications of design specifications.

COMPARATIVE QUANTITIES METHOD
IMPORTANCE
Take the cost of a previous project and make adjustment for
the differences to derive new project estimate
Uses closest matched part as basis
Rationalize cost difference based on related parameters.
Material cost differ from fluctuation on previous project

WHEN USE COMPARATIVE QUANTITIES METHOD
When having the same type of building but with different
specifications
Don’t have a lot of information on your current project but
have past project which are similar
Cost based on independent variable and dependent
variable
Complexity factors of the new project

ADVANTAGES OF COMPARATIVE QUANTITIES METHOD
Allow the BQ to be
completed faster
Not that costly

DISADVANTAGES OF COMPARATIVE QUANTITIES METHOD
Less accurate May be different from the
previous project
Require considerate
experience to do well

METHOD TO USE
WHICH METHOD TO USE?
Medium-cost housing Time given : 1 day
Based on Preliminary
Sketch Drawing
SQUARE METRE METHOD

REASON TO USE
Estimation can be obtained quickly
Applicable at the very early stage, based
on Preliminary Drawing
SQUARE METRE METHOD
Can compare for better alternative
drawing/scheme (different shape and
size)
Flexible & adaptable method

REASON TO USE
SQUARE METRE METHOD
Does not require much expertism
Meaningful and easily understood by
all parties
Lesser work and complication (does
not need to build up composite rate)

THANK YOU

Estimating presentation (final)

More Related Content

Similar to Estimating presentation (final)

More from Lam Yu

Recently uploaded

Estimating presentation (final)