Clients of the construction industry often express their dissatisfaction with the

performance of the industry. This criticism comes on the basis that clients want

greater value from their investment on project and achieve a product this is delivered

in a timelier fashion, and of quality standards. The supply team has raised concerns

that construction has a low and unreliable rate of profitability, and thinks that efforts

are not generally being rewarded accordingly for all the hard works, safety measure,

challenges and difficulties encountered bringing these projects to completion. While

all these factors and more plague the construction industry, this is also coupled with

mistrust and the engagement of blame game. However, the manufacturing industry

on the other hand has been exceeding, using lean management principles to deliver

its products with continuous improvement.

As pointed out by (Bertelsen & Koskela, 2004) only half of the work scheduled

for a week on construction projects sometimes get accomplished. This indicates that

the construct industry needs to improve its product output and that new approaches

and concepts must be the employed. Lean thinking can be one of these

approaches. The main driver behind lean thinking is that it recognizes, only a small

fraction of total time and effort put into delivering the product adds value to the end

user. The Lean method is considered to be a dynamic process, always looking for

ways of improvement but ensuring waste elimination. (Alarcon, 2007) Defines

waste as all activities that produce cost, direct or indirect, but do not add value or

progress to the product can be called waste.

The construction process is made up of a number of activities and tasks that

is carried out to meet project goals and objectivities. Within the scheme of things

there are certain activities or task which adds direct value to the project, while some

task dont. However, tasks that do not add value to the finish product, are often

necessary components of the work that ensures the satisfactory completion of the

finished product. Example, the construction of a reinforced concrete column,

requires the sub-trade to construct the formwork in place so that the concrete can be

poured into the form. The true value of this task is the finished concrete column(s) in

place. The formwork was required for the task but in the end it has added no value

to the project. Lean philosophy are founded on the premise of the concept of

conversion and flow, where only conversion adds value to the product as pointed out

by (Alarcon, 2007). Therefore close attention should be made to those activities

bounded together when reducing or eliminating waste, thus making conversion more

efficient.

Base on study conducted by A. Serpell et.al. most waste came from flow

activity, conversion activity and management activity, as factors identified that

produce waste in construction and came from two condition which contributes to this,

are work inactivity and ineffective work. Inactive work contributes to waiting time,

idle time, traveling, resting and physiological needs. On the other hand ineffective

work contributes to reworking working slowly and inventing work (Alarcon, 2007).

Therefore, to reduce or eliminate waste the role of managers becomes critical in

providing adequate planning. The lack of poor layout distribution, poor allocation of

work, all contribute to the lack of proper planning, and thus the waste.

According to (Miller, 2009) Taiichi noted that keeping waste at absolute

minimum or elimination all together, two things must be considered. a) Improved

efficence is tied to cost reduction, and this is achieved only by producing what are

needed using minimum resources and; b) Look at efficiencies at all levels which

must be improved at every step and at the same time.

Non-value added activity can be seen as activities that has no impact on the

finish product or the activity was done poorly which could be considered a waste of

time and effort from the client perspective. Waste according to (Sayer & Williams,

2007) is an activity that consumes resources without creating value for the

customer. Seven forms of waste was identified by Ohno Taiichi, in the

manufacturing industry of which principles could be applied in the construction

industry. These key forms of waste reviewed by (Forbes & Ahmed, 2011) are

transport, waiting, overproduction, defects, inventory, motion and extra processing.

The transportation or unnecessary movements of materials from one place to

another is waste. In the case where a drywall sub-trade stock pile materials in a

common route on the site that end up requiring multiply moves of the materials. The

constant movement can cause damage to the material, use of effort and resources,

which adds no value to the work. This reflects on the level of planning, the lack of

process flow and or poor site layout.

Waiting or idle time is waste. Waiting can be caused by any reason, which

includes waiting on instruction or a go-ahead to carry out an activity. The delay or

idle time before a person can begin the next activity because the upstream task is

not yet completed. Lack of proper instruction or late decisions and or use of

resources to do the required assignment.

Overproduction is building or performing more than what is required which

does not add value to the project and thus seen as waste to the customer. For

example the block work sub-contractor move along quickly with the block work

installation without allowing the electrical nor the plumbing sub-contractors a chance

to install their first fix runs in the wall. This may results in the unnecessary cutting

and or damages to the installed block wall. Lack of work coordination can contribute

to overproduction.

Defects or rework is another form of waste. Substandard works that fail to

meet project specification often have to be redone, which is adds no value to the

project. Take the case of a tile finishes that did not follow instruction given in laying

out the tile pattern but carries out the activity differently. A task should be done right

at the first time. Remedial work to this mistake cost material, money and time.

Inventory or stock that is not currently needed in the flow of thing is non-

added value, and in this case, it is a waste of financial resource tied up in stock.

While it is necessary to have stock on hand, it poses a risk when these stock gets

damaged or loses it shelf life then these item would have to be replace when

required for installation.

Motion or ineffective movement of person not positively contributing to the

process or work flow, is a waste that does not product any addition value to the

project. This can be attributed to a worker who is carrying out an activity on a

scaffold but is constantly moving up and down in search of tool or equipment to carry

out the task. This reflect a level of poor organization, and no pre-planning of the

equipment of tool needed for the task.

Over Processing is seen as performing more operations of using excessive

specification which in itself adds no value to the project. for example the contract

manager may give a supplier last minute order approval for purchase of product that

cost more than the tendered amount in the document, because of the availability and

need to complete the task and to stay project on track. This is a scenario where

expensive material or product is being used which adds no value to the client. This

further indicates the lack of adequate planning and procurement arrangement.

However, studies have shown that waste has been identified in other area in

the construction industry that can be reduced or eliminated. According to (Alarcon,

2007) review, other authors have considered three waste areas noted; bureaucracy,

people and time. These three area could clearly address. The bureaucratic process

or top down management approach to address things. Lack of people (human

resource) with adequate skills set to assist in creative thinking thereby improving the

process of things and the time that can be saved by being effective and efficient in all

aspects of delivery.

SUMMARYThe concept of waste and value in the construction industry is considered to

be not clearly understood by construction personnels, according to (Alarcon, 2007),

and some level of training is needed so that they can improve performance by

adopting strategies that can reduce or eliminate waste in the industry. Many of the

problems associated with waste and non-value added activities can be controlled or

eliminated by first recognizing the need for improvement and then implementing new

approach and concepts to improve the processes. One such strategies that can be

adopted for improvement is lean construction principles.

Performance measurement can be use as an indicator for improvement of the

company. Egan stated clearly that measurable objectives should be set and then

focus on them by use of quantified targets. Best practices performance benchmark

targets are set for achieving the objectives. As stated in the course notes

WORKSCITEDAlarcon, L. (2007). Lean Construction. New York: Taylor Francis.

Bertelsen, S., & Koskela, L. (2004). Construction Beyond Lean: A neaw understanding of construction management. 12th annual conference in the International Grop for Lean Construction (p. 11). Elsinore, Denmark, 2004: IGLC.

Forbes, L. H., & Ahmed, S. M. (2011). Modern Construction Lean Project Delivery and Integrated Practices. Florida: Taylor & Francis Group.

Miller, J. (2009, January 18). The Toyota Production System by Taiichi Ohno, Chapter 2 Pt.1. Retrieved February 24, 2015, from Kanzen Institute: message posted to http://www.gembapantarei.com/2009/01/the toyota production system by taiichi ohno chapt 2.html

Sayer, N. J., & Williams, B. (2007). Lean for Dummies. New Jesser: Wiley Publishing.