014 changes-cost overrun measurement

CHANGES- SOURCE OF CHANGE‘COST OVERRUN MEASUREMENT’

[email protected]://www.construction-productivity.co.uk

mailto:[email protected]

During construction projects, many decisions have to be made under

uncertain conditions.

The Change/re-work problem is often caused by poor project change

management.

CHANGES- SOURCE OF CHANGE

If any assumption is proven wrong, some decisions have to be revised.

In other words, changes are often inevitable.

Designers, engineers and other professionals have to make assumptions

based on existing available information and their past experience.


How to avoid or reduce the negative impact of changes.

The need for effective change management is essential for productivity

improvement.

The key is:


Managerial Technological Social factors

SOURCE OF CHANGE-MAJOR INFLUENTIAL FACTORS

The main areas pertain to


The objective of change management is to forecast possible changes.

It can be caused by either Internal or External Factors.

Different changes may have different effects or consequences.


CHANGES- SOURCE OF CHANGE •Identify changes that have already

occurred

CHANGES- SOURCE OF CHANGE •Plan preventive impacts & coordinate

changes across the entire project.

CHANGES- SOURCE OF CHANGE •A radical change is sudden, dramatic and

has a marked effect.


CHANGES- SOURCE OF

CHANGE•Gradual Changes often occur during the

design development stage, where many decisions are fine Tuned and refined progressively.

CHANGES- SOURCE OF

CHANGE

•Radical changes occur during construction phases.

•Project changes can also be classified as “anticipated changes” and “emergent changes”.



•At a more detailed level, the causes of construction project change are usually generated from either design or construction activities.


•Changes can cause cost overrun.


CHANGES- SOURCE OF CHANGE •To reduce the negative effects of change, it is important to identify the main causes of change.

CHANGES- SOURCE OF CHANGE •How these causes can effect the KPI’s.

CHANGES- SOURCE OF CHANGE •Ask questions-how can poor communications lead to higher chance of change, how can...?



• What is the relationship between a change that has occurred with total cost of a project?


•Project characteristics, which represent the amount of information available at the early stages of a project, are often the original source of change cases as concluded from the case studies undertaken for this research - see Motawa et al. (2003b).


Motawa.A (2003)


Typical cause-and-effect relationship-Motawa.A (2003)

(Fi) Projectcharacteristics

Rij(Cj) Causesof change

RjkEk) Change effects

Change effects are the change consequences on the project parameters (e.g. time, cost, etc).

Rij and Rjk are two measures that represent the degree of dependency between Fi’s and Cj’s and between Cj’s and Ek’s.

They actually represent the sensitivity of the impact of one set of elements to variations in another set of elements.





• Identification of the parties who are affected with the cost overrun.


• Determination of the penalties or consequences to the affected parties.

CHANGES- SOURCE OF CHANGE •Consideration of the interrupted cash flow, financing costs and loss/growth of earnings.


Indirect consequences of change would always be harder to identify and define than a directly attributable consequence.

In terms of measurement, the metrics for these items will be qualitative.

Examples of such indirect consequences include:




•There is often difficulty in determining equitable adjustment compensation for the parties involved.


•It may also impact on the amount of labour that is not being effectively deployed, or result in loss of learning curve.


The team’s momentum and equilibrium may be disrupted by a change

event

Therefore causing a normally effective team to become

inefficient and ineffective for a period of time, which may

increase co-ordination failures and errors.


Change may alter the morale

amongst the project team.

Morale is a complex issue that could

severely affect the project’s performance.


Influential factors (related to early stage of project) Economical Technological Customers Stakeholders Environmental Legislative Procurement route Organizational factors Financial factors Sustainability Etc

Process model of Change Management

Pre-construction Activities Client brief Project objectives Specification Design/build-ability Constructability Contractual arrangement Planning Scheduling Estimating

Labour Characteristics Subcontracting Labour Direct labour

Management System Planning Communication Controlling Co-ordinating

Resource Management & Weather Labour selection Labour control Material selection Material handling Plant Waste on site Delay and Disruption on site

Motivating Factors Hygiene Factors

Construction Productivity

Project Performance Time Cost Quality Safety Customer

satisfaction

Rewards

Effort

Ability and skill of management and workers

Site/Project Manager Characteristics Experience/capability Leadership style Authority/influence Goal commitment Involvement

Job Satisfaction

Changes inConstruction

Projects

OmissionAdditionErrors

DesignchangeBad

weather

site conditionsUncertainty

Lack of propersite investigation

Changesmade by the

client

Resources

Scope

Goals

Remove any Ambiguity

RESOURCESSCOPEGOALS

REMOVE ANY AMBIGUITY

LeadershipCo-ordinationcommunication

Team work MORE LEADERSHIP AND TEAM,WORK LESSCHANGES TO THE ORIGINAL PLANS


Changes at theHead office and

on site

Optionalchanges

(improves thechances of

expansion andsurvivor)

Essential changes(for survivor and high

productivity)

Suddenchanges

Gradualchanges

AnticipatedNot

anticipated


Causes ofchange

EconomicalEnvironmentalTechnological

SocialGovernmental/Political

Etc.

National&

international

External

Organizational changes

Internal


Changes

Direct Indirect

Badweather

Badworkmanship

Designerror

Reworkdue to

Omitting

Additionalwork

MaterialsMachinery/equipments

Skilledworkforce

Shortageof

Dispute

Communication

Cash flow

Materials

Lowe moraleamongstworkforce

Reorganizere schedule

change workmethods

DelayCauses:

Bottleneck-uncertainty

amongst workforce-morale change-

Lack of coordination-failure-

errors

Delay

Con-currentExcusable

Suppliers

Bysub-contractor

Causedby contractor

Non-excusable

waiting time

Caused byclient

compressible

Mistakes inthe drawings

Machinerybreakdown due to

age of machine

Not enoughsupervisors

on site

Idleness

Disruption1-Lack of material

availability2-Lack of skilled

workforce3-Shortage of

Machinery/tools4-Information

availability4-Lack of good

decision making5-Bad working

relation6-Poor supply chain

7-Accidents8-Poor site layout

Changes onconstruction site

due to:

Poordetailing

Supervisorydecisions

Not fault of:client

contractorsub-contractor

etc.

LOW PRODUCTIVITY ON SITE

Changes inConstruction

Projects

Designerror

Designchange

Badweather

site conditionsUncertainty

Lack of propersite investigation

Resources

Scope

Goals

Remove any Ambiguity

RESOURCESSCOPEGOALS

REMOVE ANYAMBIGUITY

LeadershipCo-ordinationcommunication

Team work

MORE LEADERSHIP ANDTEAMWORK

LESS CHANGES TO THEORIGINAL PLANS

DirectChange

Indirect

Badworkmanship

Changesmade by the

client

Reworkdue to

Omitting

Additionalwork

BadMaterials

Reorganizere schedule

change workmethods

CHANGES- SOURCE OF CHANGE •Changes can cause cost overrun.

CHANGES- SOURCE OF CHANGE •To reduce the negative effects of change, it is important to identify the main causes of change.

CHANGES- SOURCE OF CHANGE •Ensuring that all appropriate changes are recorded’

COST CONTROL AND CHANGES

CHANGES- SOURCE OF CHANGE •prevent incorrect, inappropriate, or unauthorized changes from being included in the project.

CHANGES- SOURCE OF CHANGE •Acting to bring expected costs within acceptable cost limits.

CHANGES- SOURCE OF CHANGE •Scope change control.


CHANGES- SOURCE OF CHANGE •Once the construction work starts on site, the management team on site will be responsible for day-to-day cost control as well as other responsibilities.

CHANGES- SOURCE OF CHANGE •The CM,PM, must not only know the project’s costs to date, but also be able to project costs For any additional work.

CHANGES- SOURCE OF CHANGE •The CM, PM,.. is responsible for controlling costs to ensure that construction is completed within budget.


If any changes are anticipated during the construction process, immediate steps must be taken and they are:

1. the CM must notify the senior management as soon as possible;

2. an informed decision can be made on whether or not to proceed with the change;

3. Once the decision is made can the necessary funding be obtained?



There most be a method to report to the management the cost overrun for each activity as it happens.

Software’s such as ‘asta’ shows the cumulative cost of the project.

There is no method of estimating cost overrun for a small project or cost overrun for activities with change or disruption or delay.


Developments in Cost Control Systems forchange management There are three reliable cost control systems in

construction management. They can be used for improving cost control in

a project. 1. Short term scheduling and control. This system was developed at Loughborough

University. Its main aims are: to bring together the planning and supervision

of a project; to obtain a zero or close to zero response time


2. Project Cost model. This a system developed by Dr Martin Barnes for simulating future actions and thus guiding the managers to take immediate corrective action.


3-Quantitative scheduling One of the Construction software that provides construction cost control tool for construction management is the CFF3 for cash flow forecasting.

Version three has taken into consideration the possible deviations from estimates of cost.

As well as providing cash in patterns


It gives early warning to return back to the original estimate to carry out corrective measures.

This can be done by damping out these deviations through the remaining period of construction.

Updated estimates are provided each time an actual figure is added.

The end cost remain same as was originally estimated.


Let MD=Cost of Material /unit A =% allowed for material wastage in

Spons, Laxton, the schedule of rate. X=% actual recorded waste after

completion of the job. Productivity change relating to wastage is

measured by the difference between the expected level of waste on site.

As normally, scheduled in SPONS or LAXTON’s price book,

The actual waste on site after the completion of the job can be calculated.

CHANGES- SOURCE OF CHANGEHELPDESK PROPOSAL

1 2

12

14 17 19

13

15

16

18

3

5

4 9

6

11

7

10

21 22

20

S

8

DU=2

DU=4

DU=2

DU=6DU=8 DU=10

DU=3

DU=5

DU=1

DU=7DU=8DU=6

DU=9DU=7

DU=1

DU=5

DU=

DU=4

DU=6

DU=14

DU=12DU=10

A

B

D

F

G

K

C P Q

DU=6

DU=8

DU=3

DU=7

DU=5

UT

V

W

Y

H

L

CC

HH

EE

AA

FFX

GG

0 0

2 2

8 8

6 21

8 2914 35

DU=4E

19 42

19 43

16 16 26 26

26 48

38 38

DD

BB

22 43

32 5319 52

12 38J

20 46

32 53

R M

65 65

58 5826 49

52 52

CHANGES- SOURCE OF CHANGEFig-1 Vining St-London

Compare Actual completion time for Activities 1-2, 2-3,..against allocated time for Activities 1-2, 2-3,

Compare Actual completion cost for Activities 1-2, 2-3,..against allocated cost for Activities 1-2, 2-3,

Compare Actual waste allowed(%) for Activities 1-2, 2-3,..against allowed waste (%) for Activities 1-2, 2-3,


ACTIVITIES 1-2, 2-3, 3-4, 1-12, 1-9, ….(Before any changes and after changes)To measure Items such as: Time (increase/decrease), Cost (increase/decrease), Labour (increase/decrease), Material (Material

waste-increase/decrease) Machinery (efficiency increase/decrease).


Total material cost per unit rate=MD [A-X] EC= Estimated time for Craft to carry out a unit rate of a job. HC= Hourly rate for a Craft Operative

HL= Hourly rate for a Labour Operative EL= Estimated time for a Labour to carry out a unit rate of a job.

AC= Actual time for Craft to carry out a unit rate of a job. AL= Actual time for a Labour to carry out a unit rate of a job. PR (Loss/Gain)=MD [A-X] + {(EC . HC)+ (EL . HL)}-{(AC . HC)+ (AL . HL)}

Or PR (Loss/Gain) =MD [A-X] + HC(EC- AC)+ HL(EL- AL) PR=Productivity loss/gain per unit rate.

O

Total Productivity loss/gain (for a given activity)= Productivity loss/gain for a given unit per hour x Quantity of that activity

OR = PR x TQ Labour Productivity (Pi) for time period i=WHi /Qi WHi = Total work hours charged by the crew for time period of i Qi = Quantity of work placed during period i in unit rate


Net Rate

Gross Total Total Total Total Total Time

Total Time

Total Cost

Total Cost

Total Time

Total Time

Total Cost

Total Cost

Unit

(£) Rate Quant-

Quant-

Cost Cost Est- Est- Est- Est- Act.- Act.- Act- Act-

(Est-) (Act-) (Est-) (Act-) Craft Labour

Craft Labour Craft Labour Craft Labour

(£) (£) (£) (Hrs) (Hrs) (Hrs) (Hrs) (Hrs) (Hrs) (Hrs) (Hrs) 64.5

5 72.94 160 - 1167

0 - 464 688 3257.3 3969.7

5 - - - - M2

57.29

64.73 130 - 8414.9

- 63.75 315.9 447.15 1822.75

- - - - M2

40.81

46.12 225 - 10377

- 506.25

393.75

3553.9 2271.95

- - - - M2

35.24

39.82 410 16326

- 922.5 451 6475.95

2602.25

- - - - M2

13.91

15.98 440 - 7031.2

- 638 484 4478.75

2792.7 - - - - M2

5.04 5.69 1125 - 6401.3

506.25

258.75

3553.9 1492.95

- - - - M2

3.99 4.5 785 - 3532.5

196.25

102 1377.7 588.55 - - - - M2

26.88

30.37 90 - 2733.3

- 90 54 631.8 311.6 - - - - M2

Net Rate


Total Time

Total Cost

Total Cost

Total Time

Total Time

Total Cost

Total Cost

Unit

(£) Rate Quantity

Quantity

Cost Cost (Est-) (Est-) (Est-) (Est-) (Act.-)

(Act.-) (Act-) (Act-)



(£) (£) (£) (Hrs) (Hrs) (Hrs) (Hrs) (Hrs) (Hrs) (Hrs) (Hrs)

64.5 72.94 114 - 8315. - 330.6 490.2 2320.8 2828.4 - - - - M2


CHANGES- SOURCE OF CHANGEProductivity measurement table-related to case no.1

CRAFT/LABOUR

PRODUCTIVITY

CASE NO.1 POOR

Total MD =Cost of material

Waste Waste Craft Optve

Craft Optve

Labour Labour

Productivity Loss or Gain £

Total loss/Gain =PR x TQ

Unit

3x3 Bed House-2 Story level

Quantity (TQ)

Delivered to site

(Estimate)

(Actual)

Hrs Hrs Hrs Hrs- PR=MD[A-X]+HC(EC-AC) +HL(EL-AL)

LOSS £

Description-Activities

(Act-) % % (EC) (AC) (EL) (AL)

SUPERSTRUCTURE

Facing Brick P.C £350 PER 1000 /Common Block

156 31.14 5% 6.50% 2.55 2.58 1.95 1.97 -0.9 -140 M2

Common Brick/Block

264 18.88 5% 6.50% 2.25 2.26 1.75 1.76 -0.47 -124 M2

Internal Walls-LWC Block

282 8 5% 7.00% 1.45 1.47 1.1 1.12 -0.38 -107 M2

Internal Walls-Plastering-13mm thick

708 1.71 5% 6.50% 0.45 0.45 0.23 0.23 -0.03 -24 M2

Internal Finish-Ceiling finish-set

504 0.47 5% 6.50% 0.25 0.25 0.13 0.13 0.47x (-0.02) 4 M2

Wall Tiling-152x152

75 14.5 5% 6.50% 1 1 0.6 0.6 1.71x (-0.02) 22 M2

COST OVERRUN MEASUREMENT

Formula one

PR (Loss/Gain) =MD [A-X] + HC(EC- AC)+ HL(EL- AL)

Formula two

AC = a EC (1+Σ xi) and similarly AL = a EL (1+Σ xi)

xi = % of influential factors such as weather, crew size, absenteeism, machinery,

accidents on site, etc.


1. Consider formula one and two2. Consider activity 13-16 (fig-1 Vining St)3. Project manager asks for a change to the activity

(13-16)4. As a result KPI’s for this activity will alter5. To calculate Time, cost, Material waste, etc6. Formulas one and two are used.7. Table one shows changes8. Time overrun, cost overrun etc. Is as a result of

changes made to activity 13-16 (Code-C/FB13-16)9. Therefore, total project time, cost etc will change.


CASE NO.1 POOR



Craft Optve

Labour Labour Productivity Loss or

Gain £


Unit


Quantity (TQ)

Delivered to site

(Estimate)

(Actual) Hrs Hrs

Hrs Hrs- PR=MD[A-X]+HC(EC-AC) +HL(EL-AL)

LOSS £


(Act-) % % (EC) (AC) (EL) ()

SUPERSTRUCTURE


156 31.14 5% 6.50% 2.55 2.58 1.95 1.97 -0.9 -140 M2

Common Brick/Block

264 18.88 5% 6.50% 2.25 2.26 1.75 1.76 -0.47 -124 M2

Influential factors (related to early stage of project) Economical Technological Customers Stakeholders Environmental Legislative Procurement route Organizational factors Financial factors Sustainability Etc

Process model of Change Management

Pre-construction Activities Client brief Project objectives Specification Design/build-ability Constructability Contractual arrangement Planning Scheduling Estimating

Labour Characteristics Subcontracting Labour Direct labour

Management System Planning Communication Controlling Co-ordinating

Resource Management & Weather Labour selection Labour control Material selection Material handling Plant Waste on site Delay and Disruption on site

Motivating Factors Hygiene Factors

Construction Productivity

Project Performance Time Cost Quality Safety Customer

satisfaction

Rewards

Effort

Ability and skill of management and workers

Site/Project Manager Characteristics Experience/capability Leadership style Authority/influence Goal commitment Involvement

Job Satisfaction

Product Improvement Tools (PIT) Earned Value Management (Evma) Lean Construction (Lcon) Benchmark (Ben) Front End Management (Fema) Just In Time (Jiti) Benchmarking (Bing) Quality Control (Qcon) Supply Chain Management (Scma) Buildability (Buil) Quality Assurance (Qass) Value Engineering (Veng) Buildability/Deconstruction (Buil/Deco) Quality Management System (Qmsy) Value Management (Vman) Otherp Product Improvement Tools

To have realistic cost overrun of a change or several changes- add % of variables in Product Improvement Kit tool into Formula one.

Some highly productive construction firms consider one or more variables in (PIK tools) within their management improvement policies.

Therefore, items relevant in the (PIT’s) is added to formula one.


PR (Loss/Gain) =MD [A-X] + HC(EC- AC)+ HL(EL-AL) AC = a EC (1+Σ xi) and similarly AL = a EL (1+Σ xi)xi = % of influential factors such as weather, crew size,absenteeism, machinery, accidents on site, etc.

Let us assume that in fig-1 Project – Project management have

adopted Earned Value Management (E vma) ,Buildability/Deconstruction (Buil/Deco) , Value Engineering (V

eng).Therefore new formula is:


Inside PIK box we have: Benchmark (Ben) Benchmarking (Bing) Buildability (Buil) Buildability/Deconstruction (Buil/Deco ) Earned Value Management (Evma) Font End Loading Quality Control (Qcon) Front End Management (Fema) Quality Assurance (Qass)


Quality Management System (Qmsy) Lean Construction (Lcon) Just In Time (J) Supply Chain Management (Scma) Value Engineering (Veng) Value Management (Vman) Other Product Improvement Tools (Ben)+ (Bing)+ (Buil) +.........= Σ(PIK’s)


How to calculate PIKs ( (E vma) + (Buil/Deco) + (Veng)+...)) Planning Engineer's total salary = TS (per year) or PH (Per

Hour) Let us assume that the Average Time spent for Vining St

project for carrying out VE, TQM, QA, FEL, JIT, Lean Construction etc. = AT

% of (At) used for activity (13-16) is obtainable from Planning Engineer=let us assume that 2.2% of total cost was used for all the relevant PITs.


2.2% of Total Cost(TS)=2.2% X TS=CS Let us assume that 4 major changes has been

recorded. Planning Engineer’s calculation suggest that 12.5% of

cost overrun for change during activity (13-16) is (12.5/100) x CS =Total Cost Overrun for activity=TCO

Therefore, PR (Loss/Gain) as a result of changes for Activity 13-16 =

MD [A-X] + HC(EC- AC)+ HL(EL-AL) –( 12.5/100 X 2.2 X TS )

When AC = a EC (1+Σ xi) and similarly AL = a EL (1+Σ xi)


Also considering:1. The Arithmetic Mean2. Geometric Mean The Arithmetic Mean can be applied for

individual projects. Geometric Mean can be considered for

more than one project cost overrun of more than 1 project can

cause financial loses



The geometric mean between two numbers is:

The arithmetic mean between two numbers is:

Matrix Multiplication


Matrix cost overrun after a change

bdb

A ;11

m × n matrix and s is a scalar

310221

A

930663

331303232313

3A

Square matrix

A

a11 ,, a1n

a21 ,, a2n

am1 ,, amn

Aij

Square matrix with ones on the diagonal and zeros elsewhere.

Square matrixExample:

Solution:


Definition Let A = [aij ] be an m ´ n matrix and B = [bij ] an n ´ p matrix.

Then v the product of matrices A and B, denoted AB, is the m ´ p matrix C = [cij ] where


FIG-1

Fig-1 illustrates a matrix product AB, where A is m ´ n and B is n ´ p.

Inner Products

Vector Inner Product(Dot Product)

<a|b> =

ponml

***** zyxwv ***** pzoynxmwlv

By Definition acbcba

An Outer Product is a Ket multiplied by a Bra


|a><b| =

ponml

=

*****

*****

*****

*****

*****

pzpypxpwpvozoyoxowovnznynxnwnvmzmymxmwmvlzlylxlwlv

***** zyxwv


1 2

12

14 17 19

13

15

16

18

3

5

4 9

6

11

7

10

21 22

20

S

8

DU=2

DU=4

DU=2

DU=6DU=8 DU=10

DU=3

DU=5

DU=1

DU=7DU=8DU=6

DU=9DU=7

DU=1

DU=5

DU=

DU=4

DU=6

DU=14

DU=12DU=10

A

B

D

F

G

K

C P Q

DU=6

DU=8

DU=3

DU=7

DU=5

UT

V

W

Y

H

L

CC

HH

EE

AA

FFX

GG

0 0

2 2

8 8

6 21

8 2914 35

DU=4E

19 42

19 43

16 16 26 26

26 48

38 38

DD

BB

22 43

32 5319 52

12 38J

20 46

32 53

R M

65 65

58 5826 49

52 52

Net Rate


Total Time

Total Cost

Total Cost

Total Time

Total Time

Total Cost

Total Cost

Unit

(£) Rate Quant-

Quant-

Cost Cost Est- Est- Est- Est- Act.- Act.- Act- Act-



(£) (£) (£) (Hrs) (Hrs) (Hrs) (Hrs) (Hrs) (Hrs) (Hrs) (Hrs) 64.5

5 72.94 160 - 1167

0 - 464 688 3257.3 3969.7

5 - - - - M2

57.29

64.73 130 - 8414.9

- 63.75 315.9 447.15 1822.75

- - - - M2

40.81

46.12 225 - 10377

- 506.25

393.75

3553.9 2271.95

- - - - M2

35.24

39.82 410 16326

- 922.5 451 6475.95

2602.25

- - - - M2

13.91

15.98 440 - 7031.2

- 638 484 4478.75

2792.7 - - - - M2

5.04 5.69 1125 - 6401.3

506.25

258.75

3553.9 1492.95

- - - - M2

3.99 4.5 785 - 3532.5

196.25

102 1377.7 588.55 - - - - M2

26.88

30.37 90 - 2733.3

- 90 54 631.8 311.6 - - - - M2

Net Rate


Total Time

Total Cost

Total Cost

Total Time

Total Time

Total Cost

Total Cost

Unit

(£) Rate Quantity

Quantity

Cost Cost (Est-) (Est-) (Est-) (Est-) (Act.-)

(Act.-) (Act-) (Act-)



(£) (£) (£) (Hrs) (Hrs) (Hrs) (Hrs) (Hrs) (Hrs) (Hrs) (Hrs)

64.5 72.94 114 - 8315. - 330.6 490.2 2320.8 2828.4 - - - - M2

Productivity measurement table-related to case no.1

CRAFT/LABOUR

PRODUCTIVITY

CASE NO.1 POOR



Craft Optve

Labour Labour

Productivity Loss or Gain £


Unit


Quantity (TQ)

Delivered to site

(Estimate)

(Actual)

Hrs Hrs Hrs Hrs- PR=MD[A-X]+HC(EC-AC) +HL(EL-AL)

LOSS £


(Act-) % % (EC) (AC) (EL) (AL)

SUPERSTRUCTURE


156 31.14 5% 6.50% 2.55 2.58 1.95 1.97 -0.9 -140 M2

Common Brick/Block

264 18.88 5% 6.50% 2.25 2.26 1.75 1.76 -0.47 -124 M2

Internal Walls-LWC Block

282 8 5% 7.00% 1.45 1.47 1.1 1.12 -0.38 -107 M2

Internal Walls-Plastering-13mm thick

708 1.71 5% 6.50% 0.45 0.45 0.23 0.23 -0.03 -24 M2

Internal Finish-Ceiling finish-set

504 0.47 5% 6.50% 0.25 0.25 0.13 0.13 0.47x (-0.02) 4 M2

Wall Tiling-152x152

75 14.5 5% 6.50% 1 1 0.6 0.6 1.71x (-0.02) 22 M2

CostcontrolInput

DataProcessing

Output

ContractDocuments

Stored DataPrice book

etc

DataBase

DisplayCost

Overrun

LabourActivities

1-2,2-3,...

15-16

Materials

Machinery

FormulasAC = a EC (1+? xi) and similarly AL = a EL

(1+? xi)

FormulaPR (Loss/Gain)=MD [A-X] + {(EC . HC)+ (EL

. HL)}-{(AC . HC)+ (AL . HL)}

Labour Productivity (Pi) for time periodi=WHi / Qi


Waste Waste

Quantity (TQ)

Delivered to site

(Estimate)

(Actual)

(Act-) % %

156 31.14 5% 6.50%

264 18.88 5% 6.50%

282 8 5% 7.00%

708 1.71 5% 6.50%

Costoverrun?

c

Yes

No

Highproductivity


Labour(Actual)

with cost overrunactivities

4-6

1-12

3-4

Labour(Estimates)

4-6

1-12

3-4

5-7

Materials(Actual)

with wasteincrease

4-6

1-12

4-6

Machinery(Actual)

Lossof

efficiency(%)

1-2

2-3

Materials(Estimate)

4-6

1-12

4-6

Machinery(Estimate)

1-2

2-3

3-5 Database

5-7

PR (Loss/Gain)=MD [A-X] +HC(EC- AC)+HL(EL- AL)

AC = a EC (1+? xi) and similarlyAL = a EL (1+? xi)

xi = % of influential factorssuch as weather, crew size,

absenteeism, machinery,accidents on site, etc.

c

Cost overrun documentLabour

MaterialsMachinery

send tomanagement team
