BIM Environment: Quantity Surveyor’s Information

Lifecycle Abstract:

With the increasing implementation of Building Information Modeling, the quantity

surveyors’ fundamental responsibility of measuring and pricing is being challenged. For

the continuation of their professional position within the industry, quantity surveyors

need to be able to find information and knowledge based services provided, where

requires quantity surveyor’s insight view and analysis on the information from various

sources. However, throughout the building process quantity surveyors make decisions

based on subjective judgments about the value and quality of the information; still they

rarely find the key information to get the task done. The value and quality of

information are both different in nature; information quality is context-independent,

while the value of information content-dependent. The quality and value of information

are inherently difficult to quantify, and so there is a lack of methodologies on assessing

information value and quality. The research poses the following challenges to quantity

surveyors: "How can we identify high value information within quantity surveying

firms? Is it possible to establish a filter mechanism to record the high value information

for reusing and help quantity surveyors judging the value of information?" This paper

looks to investigate quantity surveyor’s information life-cycle within design centre

environment. Investigation throughout people, process, and technology indicate that

existing working flow is hard to be changed. At current stage of BIM, its contribution is

focusing on bills of quantities. Because of lacking of a sufficient filter mechanism,

quantity surveyor can not provide the insight view of information, where already been

recorded throughout construction project process, e.g. Life Cycling Costing (LCC).

Technology is available on providing such service, but the development on such system

is stopped.

Keywords: value of information, quantity surveyor, building information

modelling (BIM), Life Cycling Costing.

Introduction

Quantity surveyors exist everywhere in the construction industry (Poon 2003).

Conventionally, quantity surveyors’ services are utilizing at the stage of costing a

design, e.g. the preparation of preliminary estimates and feasibility studies, cost plans

and schedules; and the production of procurement and construction documentation.

(Ashworth & Hogg, 2007) Due to increasingly sophisticated computer applications, e.g.

Microsoft Excel, Buildsoft, and Computer Aided Taking-off (Matipa, Kelliher, &

Keane, 2008), as well the emerging of Building Information Modeling (BIM), quantity

surveying is argued to be a dying profession. (Aouad et al., 1993; Olatunji, Sher, & Gu,

2010) Notwithstanding the observation shows that there has been a suppressed demand

for the essentially traditional and technical skills of surveyors(RICS, 2002), ‘costing a

design’/’design to a cost’ is still where quantity surveyor can contribute their knowledge

and skill. The main reason is that it is difficult to produce estimation at conceptual stage

(Matipa et al., 2008) because they require the ability not to count the bricks, windows,

and doors but the ability to presume the specific product information in line with the

designing concepts. However, quantity surveyors are struggling on meet the demand for

‘value for money’ by wasting their time on measuring and lacking of the insight of

information. Regarding measurement, not till recently, quantity surveyors typically

begin by digitizing the architect’s drawings, or importing their CAD drawings into a

Computer Aided Taking off(CATO) package, or doing measurement manually, where

consuming 50~80% of quantity surveyor’s time spending just on quantification. (Revit,

2006; Sabol, 2008) On the other hand, concentration on technology over last 20 years

(National Computing Centre, 2010) leads to the development of object-oriented CAD

and a further step to BIM, which offers a common information repository for all

participants, including quality, time and cost information together. BIM is claimed to

release quantity surveyor from the tedious task of quantifying, and allows them to focus

on higher value project-specific factors, e.g. identifying construction assemblies,

generating pricing, factoring risks etc. (Barker, 2011; Matipa et al., 2008; Matthews,

2011; Revit, 2006; Sabol, 2008) Although BIM is academic sounds, and opens

opportunities for quantity surveyor concentrating their attention on high-value factors,

but the responds from industry is not good as we expected (Howell & Batcheler, 2005).

“BIM is best viewed as just one of many purpose-built models, as a ‘source’ of information about the building, rather

than being viewed as a ‘destination’ for every item of information about the project.”

From this point of view, BIM is a concept for organizing and sharing building

information, which are far from fully mature as well. The level of detail is still varying

depending on the project phase. (Sabol, 2008) suggested that

‘Firms employing BIM will need to develop methods and standards for object development that support the level of

detail required for useful estimates, as well as provide a framework for providing consistent information for the BIM

components tallied by cost estimators’.

Regarding the technological part, there are varies applications lead BIM to Costing, e.g.

Application Programming Interface (API), and ODBC connection (Revit, 2006), which

all depend on production of consistent shared information across the project. It is crucial

that populate the database with the relevant information, as if information is incomplete

or out of date or inaccurate, the representations and coordination can be misled. (Harty,

Throssell, Jeffrey, & Stagg, 2010) Consequently, it leads to a fundamental question

‘What information must be exchanged by parties in order to meet their respective

responsibilities?’.(Chiara & Talbot, 2006) BIM assemble and shape various actors

involving in the project, and brings a new way of managing information and

collaborating throughout the project. Information will not necessarily be scarce in BIM,

though well-analysed, well presented, and well-disseminated information is not always

available. It is prudent to evaluate information, not only of quality but also value for

consolidating the use of BIM. Thus a sufficient information evaluation methodology, to

filter high value information for reuse, retain, and accumulate, is urgently required in

quantity surveying organisations.

BIM in Reality from a perspective of QS

Searching for a definition of BIM, which varies at the beginning, different software

vendors provide varies definitions. (Raic Practice Building, 2007) Till recently,

academics and industry participants reached the consensus that incorrectly seen as a

technological solution to object-oriented CAD, BIM’s core heart is sharing and

exchanging information. BIM is placing ‘information’ at the heart of the construction

process(National Building Specification, 2011; National Institute of Buidling Sciences,

2007), where enhanced visualization and automatic scheduling is a side part. National

Building Specification (2011) also revealed that 45% responds just aware of BIM, plus

13% aware and currently using BIM, by holding the definition that

‘Building Information Modelling is the process of creating and using electronic data models of buildings to facilitate

a co-ordinated understanding of a broad range of real world building issues, both as a design/specification tool and as

an analytical tool for achieving statutory approvals or client driven performance requirements.’

People

Nowadays, the key difference between recent debate and the original one is that BIM is

being used on some major projects universally, e.g. the Freedom Tower in New York

City, BIM solution: Autodesk REVIT (Autodesk, 2005), The Bart’s and The London

Hospital project, BIM solution: Autodesk Architectural Desktop(Harty et al., 2010),

refurbishment of the Sydney Opera House, BIM solution: Bentley’s BIM tools(Bentley,

n d), and the Eureka Tower in Melbourne, BIM solution: Graphisoft’s

ArchiCAD(GRAPHISOFT, 2002). Without commenting on any one specific BIM

system, it does serve well to demonstrate some of BIM’s inherent limitations by

studying these live projects. (Howell & Batcheler, 2005)

Figure 1 QS Working flow with BIM implementation (adopted from (Xu & Tang, 2011))

Standard Methods

of Measurement

Tangible Information Entity:

E.g. Taking off

Bill of quantities

Context-bearing

E.g. Title

Along

with

stan

dard

s

Quantity surveyor

Using CATO etc.

Measurements on

buildings

Informatio

n

Fragment

Viewed as

Information

Object

Viewed as

Data

Viewed as

Tangible container:

Drawings

(with physical feature of building

And their meaningful relationship)

Intangible

Information

Entity:

Knowledge

Alie

n w

ith B

uild

ing

Info

rma

tion

Mo

de

ling

Tangible Information Entity:

E.g. Taking off

Bill of quantities

Context-bearing

E.g. Title

Checking on SMM

Measurements on

buildings

Informatio

n

Fragment

Viewed as

Information

Object

Viewed as

Data

Viewed as

Building Information Model

API, ODBC connection

Alo

ng w

ith

stan

dard

s

Literature review on the lessons learned from these real project, as well considering

BIM from a measurement and costing perspective, figure 1 above shows the comparison

between traditional workflow within quantity surveying firm and workflow in BIM

solutions, on the left is the traditional working flow of quantity surveyors, which

interpreting drawings manually, however, with inexorable advance of computing

technology, quantity surveyor’s productivity is improving by Computer Aided Taking

off (CATO). BIM solutions, which mainly consist of object-oriental CAD, is claimed to

automate the tedious task of quantifying. However, the reality is that BIM data still need

to be filtered that they can comply with the rules, the Standard Methods of

Measurement(SMM). (Olatunji et al., 2010) Therefore, quantity surveyors still need to

spare times on measurement by checking their compliance with SMM. Additionally,

figure 1 also implies one limitation that being discovered from live project, which is

sharing BIM information as drawing files. This phenomenon is against the definition of

BIM, but existing in the real world. (Howell & Batcheler, 2005) This discussion is

beyond this research, but address the problem that it is not reasonable to expect that the

use of BIM can influence or abandon the project team’s individual work process, or

switch the tools they familiar with.

Process

During traditional process of construction project, accurate, practical costing

information is difficult to be defined, especially in the early stages, e.g. preliminary

design. With the adoption of BIM, which a new concept on organizing information

throughout project, project information at these early stages is still general and at a high

level, e.g. number occupants, gross square feet area, and enclosed volume. Standard

CAD, Object-oriental CAD, and now BIM, technologies have provided information far

in excess of what is needed. Detailed and poor organized models can confuse decision-

making, unless delineating what information is required to support the decision-making

processes.

Figure 2 Quantity surveyor’s service during phases of construction project

Pre-Project Planning Preliminary Design Design Bidding Procurement Construction Operations

Info

rma

tio

n S

erv

ice

sB

IM im

pa

ct o

n c

ost

Info

rma

tio

n g

en

era

ted

by p

ha

se

sB

IM M

od

el L

eve

l

(Pro

po

se

d)

0%

20%

40%

60%

80%

100%

120%

General Conditions Structural Mechanical, Electrical, Plumbing Finishes Overall

Cash flow analysis

· General Conditions

· Overhead and Profits

· Management fees

· Design Contingency

· Escalation

Construction· Sitework

· Foundations

· Floor systems

· Columns

· Roof systems

· Exterior wall

· Interior wall

· Exterior Glazing

· Doors

· Specialties

· Conveying system

· Plumbing

· Fire protection

· Heating, Ventilating

· Air conditioning

· Electrical

Building Related

Costs· Operation

· Maintenance

· Replacements

· Alterations

Building Related

Costs· Financing

· Taxes

Life Cycling Costing· Non-building Costs

· Building Related Costs

· Building Costs

Building Costs· Site development

Non-Building Costs· Administration

· Financing

· Legal

· Surveys

· Land purchase

· Fees

· Furniture & Equip.

· Contingencies

Building Costs· Architectural

Building systems

Building Costs· Structural

Building systems

Building Costs· Mechanical

Building systems

· Electrical

Building systems

Exporting quantities

And

components informationPricing feedback

Pricing feedbackExporting quantities

Track changes

Discrepancy feedback

Value for money Analysis

Lesson learned database

Variation orders Certificates

Certification of Payments

Final

Account

Variation

orders

Valuation

Pricing

Tendering

DocumentsContract

Cost plan Bills of Quantities

Cost Estimation

A study had been conducted throughout the construction project phases to reveal the

contribution of BIM on the quantity surveyors’ work. (See above Figure 2) Start from

cost plan, at the conceptual level, costing is generally based on templates from past

project experience, or on standard square foot costs based on project type, region, or

type of construction, where impossible on counting of individual pieces. With the

development of project definition, cost plan (e.g. ‘standard cost $ × sq. ft.’) turns into

cost estimation, where bill of quantities can be conducted. Additionally, cost estimation

should extract certain information from cost plan, in other words, split ‘standard cost$’

into elements pricing, and split ‘sq. ft.’ into bill of quantities. Apparently, at the initial

phases, the information is vogue, and the bill of quantities is roughly calculated, where

the elements are more likely an unspecified none, e.g. doors, windows, etc. The level of

detail depends on the phase of the project, from ‘door’ to ‘flush door’ to ‘5-Ply Particle

Core WDMA Extra Heavy Duty PC-5 Flush door’, where end with a well-defined level

of detail. In BIM situation, this information can be acquired from model automatically,

where claimed to save 50~80% quantity surveyors’ working time. (Sabol, 2008) On the

other hand, pricing is where quantity surveyors play the state of art, as obviously keep

the consistence on pricing from ‘door’ to ‘5-Ply Particle Core WDMA Extra Heavy

Duty PC-5 Flush door’ is very difficult and majorly depends on personal experience.

Proceeding to next phase, cost estimation consist of two single parts, which are bills of

quantities and pricing, when cost estimation phase enter into Class 1, or the Level of

project definition has been reached 50~100% (Bates et al., n d), bill of quantities and

pricing should be extracted into tendering documents for conducting estimation on

bidder price. After bidding process, both of bill of quantities and pricing have been

agreed between contractor and clients, where turns into contract documents. This

documents will be proceed, plus the difference to contract (Variation orders), to final

account.

From above figure 2, it is obviously that information is transmitted throughout the

phases, and the process should be integral. In literature, ‘cost plan’ should be consistent

with final account within a certain variable, where in line with contract types. In other

words, review ‘cost plan’ as a ‘Top-down’ estimate, where should meet with final

account, which can be regarded as a ‘Bottom up’ estimate, to some extent. A further

investigation has been conducted into information requirement of life cycling costing,

where consist of building related costs, non-building costs, and building costs.

Additionally, these three terms can be split into more detailed slots. Apart from the

requesting on these information at the beginning phases, these information is

progressive, in other words, it only can be provided out during different phases. Before

it actually happened, even specified in contract, the ‘information’ are made from all

participants’ presumption and expectation. It is widely acknowledged that the reason

why whole life costing has not been more widely used is to be the lack of appropriate,

relevant and reliable historical cost information and data. (Ashworth & Hogg, 2007)

Suermann (2009) conducted a Key Performance Indicators (KPIs) survey on BIM, 83.7%

respondents said that BIM improves cost of general conditions, structural, mechanical,

electrical, plumbing, and finishes. With a further interpretation on the original data, the

contribution of BIM on providing accurate information is focus on Mechanical,

Electrical, Plumbing phases, where the project is on constructing. It is said that Pre-

project planning, preliminary Design, and Design phases are the three most important

phases that have ability to impact cost and functional capabilities dramatically, where

leaving these decision stages with loads of assumptions will highly influence the cost of

design changes. (The Construction Users Roundtable, 2004) However, to author’s

knowledge, apart from operation, maintenance, replacements and alterations cost

information, the rest of the information are all contained in the information services

where quantity surveyor provided. Because of without a sufficient filter mechanism,

they are all drawn in these paper documents. Additionally, information technology is

helping us on converting paper-based documentation to the Electronic Document

Management System (EDMS), where can be an automated process on analysing data.

Technology

Traditional information and communication technology approaches to sharing static

project information via file exchange, e.g. .dxf, .dwf, and .pdf, do not transfer the

dynamic object intelligence, where requires quantity surveyor to put their efforts on

measurement. To current stage of BIM, where objects and assemblies can be encoded

into the model to some extent, cost applications can harvest information from BIM

objects, and to really appreciate the true benefits of BIM, the information in the models

must be coordinated with information in master specification systems. (Gu, Singh,

London, Brankovic, & Taylor, 2008; National Institute of Buidling Sciences, 2007)

As discussed in previous section, it is not reasonable to expect that the use of BIM can

influence or abandon the project team’s individual work process, or switch the tools

they familiar with. Quantity surveyor requires a mechanism to cull object information

from the model, identify and export such information and quantities, e.g. assemblies,

and families, to their purpose build models. Additionally, such mechanism is suggested

to be bi-directional to gradually consolidate the database of alternatives and

substitutions of design models within BIM. (Sabol, 2008) Furthermore, such filter

mechanism can be accomplished in several approaches, e.g. Application Program

Interface (API), Open Database Connectivity (ODBC), and Industry Foundation Classes

(IFC).

BIM acts as a common information repository for all project participants, where multi

parties can tap into a construction project, and derive object information for their

purpose or tasks, such as environment test, energy consumption analysis, and costing

analysis. Therefore, BIM data must consistent with purpose-built models, where raise a

hypothesis that BIM can be and should be an open database for project information, and

allow the re-use of project data which has already been created during the process and

thus ensure consistency between each of these purpose build models as different

representations of the same building. In other words, is there a need for BIM database to

filter high value information, furthermore to sort them for particular user?

Value for Money, Money for Information

Clients pay massive fees for Quantity surveyor’s information based service on ‘Value

for Money’. However, it is interesting to address that quantity surveyor struggling on

the accurate measurement of quantities for decades, where is the barrier on getting the

insight view of information, and BIM now is providing the capability to release quantity

surveyor on counting components of building, and improving the accuracy on cost

information throughout the entire building lifecycle. At current stage of BIM, automate

bill of quantities is where BIM contributes, it promises to free quantity surveyors to

focus on higher value tasks. It is time for quantity surveyors to chase ‘Value for

Information’.

Value for Money (VfM), as we all know, in simple, is that obtaining the maximum

benefit with the resources available, where apply this definition into ‘information’ term,

it can be that obtaining the maximum benefit with the information available.

Figure 3 Value for Information(adopt from (Improvement and Development Agency, 2010))

Value for Information

Economy Efficiency Effectiveness

Cost Input Output Outcomes

Table 1 Value for Information(adopt from (Improvement and Development Agency, 2010))

Economy

is what goes into

providing a service, such

as the cost on storing,

searching, and achieving

information.

Cost

reducing costs for the same outputs

Input

reducing inputs (eg, people, materials, time, effort) for the same outputs

Efficiency

is a measure of

productivity ie, how much

you get out in relation to

what is put in. Output

getting greater outputs with improved quality (eg, extra service or productivity) for the same inputs

Effectiveness

is a measure of the

impact that has been

achieved, which can be

either quantitative or

qualitative.

Outcomes

getting proportionally more outputs or improved quality in return for an increase in resources.

Discussion on Value for Information can be started from three terms, Economy,

Efficiency, and Effectiveness. Firstly, Economy is the cost on storing, searching, and

achieving information, where we have invested money over last two decades. (National

Computing Centre, 2010) The development on the software is reducing inputs for the

acquisition, storage and processing of data, where also improving the efficiency.

However, there is a lack of information assessment methodology within quantity

surveying firms to record high value information for reusing and helping quantity

surveyors study on historical data of buildings, and then provide the value for

information.

Conclusion

Ideally, BIM is an open database for exchanging building information, is a central

detailed intelligent information database. BIM provide the capacity on breaking down

the inherent barrier on communication between all participants. Regarding the Quantity

surveying profession, it is essential to develop processes and methods throughout

project phases for using BIM-based costing, otherwise sharing BIM as drawings with

intelligent information will be another phenomenon. On the other hand, it is

unreasonable to expect that using BIM can influence individual work process or switch

their familiar tools, therefore, exporting components information for cost application is

also important. Furthermore, this leads to an urgent question on how to keep consistence

on the information services from quantity surveyors.

We can conclude that information regarding Life Cycling Costing (LCC) can be all

recorded by BIM database. However, at current stage of BIM, these information is not

well organized, well presented for quantity surveyor and other participants to reuse and

to setup lesson learned database, where preventing the development on Value for

Information. Technology is reducing costs and inputs for the same outputs, but for

getting greater outputs and more outcomes, where is quantity surveyor’s looking for

value for information.

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