Construction Productivity

How does productivity varies by day of the week?

"Blue Monday Syndrome" decreases beginning of the week productivity. Cumulative fatigue at the end of the week can decrease productivity. People tend to not want to work weekends (you loose about half your usual productivity on the weekend). There is less support/supervision on weekends. Also, Saturday is sometimes a makeup day.

How can a contractor recruit/attract skilled craft workers to a construction project?

1) wage rates 2) per diem 3) overtime 4) completion (ROF) bonus (ROF - Reduction of Force) 5) safety bonus 6) relocation assistance.

List two ways in which PPMOF practices may increase some project costs?

1) Engineering. Increased design detailing is necessary. 2) Transportation. 3) With limited availability to inspect, the prefabricated material may not meet expectations and must be remade, driving up costs.

List the three primary recognized paths to productivity improvement...

1) Increase the percentage of time spent by craft professionals on direct work. 2) Reduce the number of work hours required to complete one unit of work. 3) Reduce the amount of rework that occurs on projects.

How can adverse weather be mitigated?

1) Mudslabs to mitigate wet weather conditions 2) Lime treatment to mitigate wet weather on construction roads and lay down areas 3) enclosure systems and heating for cold weather concrete lays 4) cool down stations for used during extreme heat

What are the sources of rework?

1) Owner change - owner changes projects definition, scope or requirements. 2) design error/omission - necessary items or components in the project design are erroneous or omitted. 3) design change - changes are made in the project design or requirements 4) vendor error/omission - necessary items or components are erroneous or omitted by vendors. 5) constructor error/omission - errors or omissions in construction methods, procedures, activities, or tasks. 6) constructor change - changing constructors, construction methods or procedures. 7) transportation error - mistakes, accidents, or errors in transportation 8) other - misplaced designs, having old designs, etc.

What are some temporary facilities that you need to strategically place on the layout of your worksite?

1) Parking facilities 2) hiring process buildings 3) orientation and safety training buildings 4) transportation on site 5) lunch and break facilities 6) first aid and hygiene areas 7) trailers for supervision and support staff

List two way in which the use of PPMOF practices may reduce construction labor costs.

1) Reduced labor rate and no per diem in the shop environment. 2) Improved labor productivity in the shop environment. 3) Reduced scaffold and equipment costs. 4) improved labor density 5) less elevated work 6) site overhead reduction

List three potential weaknesses of the measured mile.

1) The chosen "measure mile" period must be long enough to be considered representative. The productivity during the period must be able to be sustained without impact. 2) The work being performed during the MM period must be representative of the work being analyzed outside of the MM period. This includes the type of work, the difficulty, and the crew being used. 3) The work being analyzed must only be work that was impacted by the alleged owner-caused problems. You can't include work that was not impacted by the alleged owner-caused problems. The productivity of the analyzed work must not be impacted by any contractor-caused issues.

What would a company need to assess to determine the availability of skilled craft in the area?

1) available labor sources and demand in the area 2) area employment data 3) area wage data 4) per diem requirements 5) area accommodation & service information 6) similar work in the area (can be good and bad) 7) training needs 8) labor contingency recommendation

What are the major reasons for turnover in the construction industry?

1) compensation 2) overtime available on another job site 3) work closer to home 4) inadequate tools and equipment 5) poor planning 6) poor overall management 7) mediocre supervision 8) unsatisfactory relationship with boss and colleagues 9) working environment including safety

How does PPMOF improve quality?

1) higher quality control due to controlled manufacturing conditioning and ability to weld in preferred conditions. 2) pipe and other materials are not subject to weather.

How does PPMOF cause risk in terms of engineering?

1) it requires a different engineering approach by all disciplines due to interfaces and shipping. 2) limited knowledge base of designers with PPMOF components. 3) engineering cost will be about 5-15% higher.

What are typical reasons for underreporting rework?

1) lack of rework reporting system 2) lack of training or discipline in cost code system 3) reluctance to self report mistakes

What are some typical work activities that would be included in the concrete direct work activities?

1) loading materials at the jobsite yard 2) local layout, excavation, and backfill 3) hauling to and unloading at jobsite 4) fabrication, installation and stripping forms 5) installation of rebar 6) installation of embeds 7) all concrete placement (curing, finishing, rubbing, etc.)

How does PPMOF cause risk in terms of transportation?

1) method and route of transportation impose size and weight limitations as well and width and height restrictions during transit and at the site. 2) permit requirements, restrictions, and the availability of transportation and lifting equipment.

What are some demotivators?

1) non-availability of the right material, tools, or equipment 2) poor relations between workers and management (easier to replace management usually) 3) poorly organized projects 4) breakdown in communication 5) lack of recognition of outstanding effort 6) disrespectful treatment 7) unfair work assignments 8) incomplete engineering/design work 9) lack of cooperation between crafts 10) poor supervision 11) rework 12) no participation in the decision-making processes 13) restrictive and burdensome procedures

What are the major reasons for absenteeism in the construction industry?

1) personal or family illness 2) poor overall management 3) poor supervision 4) excessive travel distance to the job 5) excessive rework 6) unsafe working conditions 7) overtime 8) lack of interest of responsibility

Provide two examples of material type in which the prefabrication process is typically employed in heavy industrial construction?

1) pipe spools 2) Structural steel or steel foundations

Why would you want to track rework?

1) recover cost associated with change 2) recover cost associated with error and omission by others 3) contractual requirements (incentives) 4) drive accountability internally 5) benchmark against industry 6) drive improvement efforts

Drivers/Benefits of PPMOF: Risk Management

1) reduced impact of the community near the site 2) Reduced risk of weather delays, environmental impacts, permitting delays, and interference with ongoing construction.

What are some factors that magnify the losses associated with change?

1) timing of the change 2) complexity of the added work 3) amount of time it takes to get the change formalized (processing time). 4) interdependencies among activities 5) intensity of the work and the amount of the room in the schedule

What should you consider when looking at material, tool, and equipment shortages?

1) tool room location 2) tool checkout efficiency 3) quantity of tools 4) quality of tools 5) management of tool return for availability 6) management of tool theft Workers want to get their jobs done, they can't do this without tools. Therefore, workers won't check tools back in.

What is the workforce view of factors that affect construction productivity?

1) tools and consumables 2) material 3) Engineering, drawings, management 4) construction equipment 5) supervisor direction 6) safety 7) communication 8) project management

To recover lost productivity costs (damages) the contractor typically must sufficiently demonstrate the following:

1. Compliance with the notice requirements of the contract. 2. The events that occurred were unforeseeable at the time of the contract or change order. 3. the events were beyond the control of the contractor. 4. The events were cause by the owner of some entity the owner was responsible for. 5. The events caused change in the performance of the work and results in increased costs or time required to perform the work.

What are the steps involved in the measured mile?

1. Determine Discipline and scope of work. 2. Determine the MM period of non-impacted work. 3. Estimate the productivity during the MM period of non-impacted work. 4. Estimated the Should Have Been productivity of the impacted period. 5. Estimated the loss in productivity and resulting cost.

Construction makes up about _____% of total US GDP

4.2%

What is the average percentage of direct costs cause by rework?

5% of total construction costs. In the US, if we work 1.3 trillion $ in construction, about 66 billion $ is rework annually.

Construction employees around how many people per year? (Data from March 2018)

7.2 million, about 4.9% of total major industry sector employment

How much has construction spending increase from January 2013 to January 2019?

8 trillion$ to 1.287 trillion$. Has increased about 5 trillion dollars.

What is a module?

A major section of a plant resulting from a series of remote assembly operations and may include portions of many systems; usually the largest transportable unit or component of a facility.

What is prefabrication?

A manufacturing process, generally taking place at a specialized facility, in which various materials are joined to form a component part of a final installation; a common practice of most industrial project today.

What is off-site fabrication?

A practice of preassembly or fabrication of component both offsite and onsite at a location other than the final point of installation.

What is preassembly?

A process by which various materials, prefabricated components, and/or equipment are joined together by different crafts at a remote location for subsequent installation as a sub-unit. It is generally focuses on a system; also a common practice on most industrial projects today.

What are some advantages and disadvantages of shift work?

Advantages: Avoid Premium Pay. Does not have the productivity losses associated with overtime or congestion. May be able to minimize the equipment rental cost if paying per day. Can give weather support if there are warm conditions during the day. Disadvantages: Not an option for many site conditions. Difficult coordination between shifts. Requires extra management support.

What are some advantages and disadvantages of overmanning and trade stacking?

Advantages: Avoids fatigue problems. Flexible option for acceleration. Disadvantages: New workers have to be brought up to speed. Can have productivity losses due to congestion. Paying for onboarding on new worker.

What are some advantages and disadvantages of extended overtime?

Advantages: Decreases overall schedule time. Attracts workers because of increased pay. Disadvantages: Premium pay. Loss in efficiency as hours per workweek increase. Requires increased management.

What are some advantages and disadvantages of sporadic overtime?

Advantages: Limited impact b/c of short duration. Handles immediate problems quickly. Very flexible. Disadvantages: Premium pay. Requires increased management. Fatigue causes productivity loss.

What is activity analysis?

Also known as work sampling, is a high level of sampling. A continuous measurement aimed to improving the amount of time that craft workers spend on actual construction. This measured time is also known as tool time, wrench time, or direct work.

What is change?

Any action, incidence or condition that makes differences to an original plan or what the original plan is reasonably based on. It is common and 5-10% cost growth due to change should be expected.

Discuss craft density and its affect on productivity...

As the workforce becomes more dense, you loose productivity. You want approximately 300 sqft /worker for there to be no loss. Example: Pulp and paper projects have limited space, so you have to determine how many crews you can fit in the space without decreasing productivity.

What do manufacturing facilities have that construction sites do not?

Automated factory assembly lines.

How does PPMOF cause risk in terms of flexibility and coordination?

Change is especially detrimental when using this approach. Coordination requirements increase significantly.

What is work sampling?

Consists of observing and classifying a small percentage of a project's labor activity. This observation is a mental snapshot, do not assume they are doing something different than what is in this snapshot.

What are the ways construction differs from manufacturing?

Construction projects ... 1) are mostly relativity short duration 2) have workstations that are not permanent 3) have unique designs 4) are usually the preliminary step, this may make access for construction difficult. 5) need highly skilled craftsmen rather than unskilled workers to do specialized tasks. 6) are usually outside, so various interruptions must be accounted for. 7) have large-scale vessels/components that are difficult to handle. 8) have deeply involved owners, while manufacturing owners are not.

What are the categories for work sampling?

Direct work Supportive work (transport, travel, instruction) Delays (personal, idle)

What are some reasonable number for these categories?

Direct work ~ 44% Travel ~ 14% Transport ~ 10% Instruction ~ 7% Idle ~ 20% Personal ~ 5%

How can management avoid rework?

Do NOT mobilize to the field prematurely. Make sure engineering is sufficiently complete to support a efficient work schedules.

Explain how project construction phases can impact productivity...

Early work phases have low productivity (resources are still being established and craft workers are being hired). Middle phase usually has the best productivity (everyone is in their own grove and they have learned their craft/area). Later phases have lower productivity (craft density is higher, congestion from installed facilities, diminishing work fronts, and punchlist work).

True or False. A generally recognized drawback of PPMOF is it typically exposes workers to less safe working conditions.

FALSE.

How does overtime specifically affect productivity?

For every 10 hours added to the work week you decrease 10% in efficiency.

What are the typical projects for heavy industrial versus infrastructure?

Heavy Industrial - oil refining, pulp and paper, power, chemical, manufacturing. Infrastructure - highway and bridge, water and wastewater, flood control and navigation, rail.

What is the typical project delivery method for infrastructure versus heavy industrial projects? Describe the differences

Infrastructure projects are typically Design-Bid-Build, where all engineering & design is completed before the bid takes place and construction begins. However, heavy industrial projects are usually "Phase Overlap" where engineering, design, and construction all take place at once.

Provide one example of how the use of PPMOF practices may have a positive impact on a construction project schedule by utilizing parallel activities performed offsite.

It can shorten project duration, help meet outage requirements and ease permit constraints. Example: Assembly can start on modules while site work and foundations are underway.

Why is the measured mile favored?

It is favored because it attempts to consider only the actual effect of the alleged impact and thereby eliminates disputes over the validity of cost estimates, or factors that may have impacted productivity due to no fault of the owner.

What is project acceleration?

It is the deliberate or unintentional speeding up of a project. It may result in overtime, second shifts, or more labor added beyond the saturation point of the site.

What is direct work rate?

Observations of direct work/Total number of observations

How does working inside an operating plant effect productivity versus working in a greenfield site?

Operating plants have space restrictions, have permitting requirements, require training for specific risks, scheduling issues, may expose workers to temperature extremes. These all reduce productivity. Greenfield sites allow for management to effectively layout site plans to create ideal conditions for workers. You want about 300 sqft/worker on site.

Lost Productivity

Planned - Actual = Variance

True of False? If the owner of a project delays a construction contractor such that work planned to be performed during a desirable weather time period must be performed during an undesirable weather time period, then they may be subject to a claim from the contractor for additional compensation due to productivity losses.

TRUE

True or False. Improved quality control is typically recognized as a benefit of using PPMOF practices.

TRUE

True or False. It is generally accepted that the use of modularization can enable shorter project durations.

TRUE.

True or False? Project construction activities during phases later in the project time period tend to have lower productivity than experienced in the middle of the project. If true, list some reasons for this.

TRUE. 1) high craft density 2) more congestion from installed facilities 3) diminishing work fronts 4) punchlist work.

What is the measure mile?

The measured mile is a widely accepted method of calculating lost labor productivity in the construction industry. This method compares identical activities in impacted and non-impacted section of the project to determine the loss of productivity result from the impact of a known set of events.

What are some sources of change?

The most common sources of "field originated changes" are differing site conditions. Examples: unexpected underlying bedrock or underground utilities.

What is a foreman delay survey?

This is sampling from a foreman, and contains reports by the foreman about causes of delays of their crew. Helps measure management's effectiveness of planning work, and allocating tools, equipment, and materials.

What is a craftsmen questionnaire?

This is sampling from craftsmen, and asks what is causing THEM problems. They are used to survey the craft on problems with the availability of materials, tools, equipment, scaffolding, etc. These surveys help isolate issues relating to rework, crew interference, job instructions, and working conditions. Helps identify inefficiencies management can improve on.

What is out of sequence work? List some causes

This is when, for some reason, you have to work out of plan. So, you move activity B up in the plan because you can't complete activity A. However, you may not be able to work on B if you don't have the appropriate materials to do so. Causes: Late design deliverables, change in design, late delivery from vendors, late scope changes, etc.

What is punchlist work?

When you turn work over to the owner, they will do an overview/inspection of the work. If anything comes back as nonconformance work it goes on the punchlist to be reworked.

With an increase in construction spending over the past 6 years, how does this affect productivity?

With a large growth and shortage of skilled workers, productivity will be lower since more people are on the learning curve... this also drives up wages.

What is the productivity ratio?

actual direct workhours/estimated direct workhours or actual labor productivity/estimated labor productivity. this provides a relative performance measure of actual versus estimated. Productivity Ratio <1 is good.

How can adverse weather affect productivity?

bad weather is to be expected on all projects. However, pushing weather sensitive work back from good weather periods into periods of bas weather, or encountering unusually severe weather can lower productivity. (example: don't move backfill and compaction work into wet weather periods)

Definition of productivity?

direct workhours / quantity installed relative efficiency of labor utilization in the construction process measured as a ratio of input to output.

What is production?

quantity installed/time this is the rate of installation in the construction process measured as a ratio of output to period of time.

How does PPMOF improve Safety?

safer working condition reducing the exposure of workers to weather, heights, hazardous operations, and neighboring construction activities.