Loqust Glossary


A3 1

A one-page report prepared on a single 11 x 17 sheet of paper that adheres to the discipline of PDCA thinking as applied to collaborative problem solving, strategy development or reporting. The A3 includes the background, problem statement, analysis, proposed actions, and the expected results.

Actual Production Line

A Production Line© representing “Actual” work progress as reported in the Loqust “Quantity Tracking” module.


The person or group that makes assignments to direct works to complete a Task. (Last Planner® in LCI terms)

Average Production Line

A Production Line© representing the completion of a Task based on its "to date" history. ("Here is how this Task will be completed if we continue doing what we have been doing")


Backward Analytical Pass

The third and last Management Centric Project Schedule step; analysis of execution metrics. Involves a repetitive comparison of actual to planed (as created in the Forward Planning Pass) performance and providing periodic completion projections based on actual progress. Backward refers to starting at the detail Task Work Structure performance and progressing to summary performance.

Backward Work Structure Pass

The first Management Centric Project Schedule step; determines a supporting Task Work Structure. Involves an analysis of sub-Tasks (Split Tasks), Tasks and Sequential Task elements necessary to manage the completion of a Project. Backward refers to starting at the detail requirement and progressing to a summary Task Work Structure.

Base Production Line

The Base Production Line is the Production Line® being compared to the Superscript Production Line. Noted as Base Production Line Superscript Production Line.

Big Room 1

Literally refers to the colocation of the design and/or construction team in one place to facilitate collaboration However, the Big Room concept is more than co-location of people; it is about fostering the collaborative behavior and the work they are producing.

Buffer 1

As a verb: “to isolate one activity from the next.” A mechanism for deadening the force of reality unfolding in a manner that is contrary to what was anticipated in the plan. For example, a capacity buffer is created by committing to complete less work than what would be achieved according to the planned capacity of the resource. If production falls behind schedule, there is capacity available for catching up. (Lean production/construction generally prefers capacity buffers to inventory buffers.)


Child Task

See Split Task

Child Work Quantities

See Split Task


Used to provide to other enterprise Project Control systems empowering the sharing of Loqust data with other systems.

Completion Line

A horizontal line on a Production Graph© representing the “Quantity at Completion” for a particular Task.


When a Successor Sequential Task is not being completed fast enough and/or a Predecessor Sequential Task is being completed too fast, progress on the Successor Sequential Task can be delayed. This is graphically represented by an intersection of the two respective Production Lines©.


A Predecessor Sequential Task or Milestone that prevents a Successor Sequential Task from being completed. For example materials being delivered late.


A group of resouces organized to compete a Task. See Dimensions.



Empowers the expansion of the 2D Production Graph to multidimensional Production Control analysis such as Location, Crew, size, color…

Dimension Group

A collection of related Dimension that can provide the basis for a Split Tasks. e.g. Location, Crew, size, color…



A collection of one or more Production Graphs© designed to provide information for specific stakeholder(s) that is shared in perpetual real time by a URL link to both licensed and unlicensed Loqust users.

Efficiency Metric

The Base Production Line is the Production® Line to which the Evaluation Production Line is being compared to when developing an Efficiency Metric. Noted as Evaluation Production Line Base Production Line.


An organization that controls one or more Projects.


Forward Planning Pass

The second Management Centric Project Schedule step; planning. Involves creating Planning Production Lines at the summary Task Work Structure level as determined in the Backward Work Structure Pass and refining to the detail Split Task level as work start dates approach. Forward refers to starting at the summary level and progressing to a detail Task Work Structure.



A collection of related Tasks; Groups can be created in a hierachal relationship allowing Groups to be used in re-creating a hierarchy of Tasks.


Kaizen 1

The Japanese word for continuous improvement. Kaizen has come to mean the philosophy of continuous improvement.

Kanban 1

Japanese term meaning "signboard"; a communication tool used in JIT production systems. The signal tells workers to pull parts or refill material to a certain quantity used in production. The Loqust anaolgy is the Production Graph© that is a visual "signboard" easily understood by all construction Stakeholders.


Last Planner® 1

The person or group that makes assignments to direct workers. Project Architect and ‘discipline lead’ are common names for Last Planners® in design processes; "Superintendent" or "Foremen" are common names for Last Planners® in construction processes.

Lazy S Production Line

A general descriptor for a typical Production Line©. It is characterized by reduced production during the beginning phase of a Task due to learning curve impact; increased production during the middle phase of a Task as a crew gains competency and reduced production during the later phase of a Task due to anticipated completion impact.

Lead/ Lag 1

The amount of time delay between a Predecessor and Successor Sequential Tasks to minimize the risk of work flow interruption. Also see Buffer.

Lean 1

Culture of respect and continuous improvement aimed at creating more Value for the customer while identifying and eliminating Waste.


Management Centric Project Schedule

A project schedule designed with "Pull" concepts designed to be managed and owned by individuals performing and managing the work.


An external schedule related event independent of a specific Task important to tracking work progress.


Native Unit of Measure

Task unit of measure used to measure work progress expressed in its native terms (e.g. Lineal Feet, pounds, cubic yards…)

Non-Working Production Line Segment

A segment of a Production Line that corresponds to Non-Working Time. Typically represented as a horizontal segment of a Production Line on a Production Graph.

Non-Working Time

Time that individuals performing work on a Task would typically not work (most commonly holidays).

Normalized Unit of Measure

Represents the percentage of work accomplished on a Production Graph. Commonly used to compare work progress of Tasks with different Units of Measure (e.g. cubic yards, Lineal Feet, ton...)



Occurs when a Task's actual Production is in excess of its planned rate Production.


Parent Task

See Split Task

Parent Work Quantity

See Split Task

Pay as Paid

A contractual term to control payment so that it is based on the same work quantity as payment received.

Pay when Paid

A contractual term to the control payment due date to be based on the same payment received date.


Stands for Plan – Do – Check – Adjust. The cycle introduced by Walter A. Shewhart and popularized by Dr. W. E. Deming as a method of continuous improvement.

Percent Promised Complete (PPC) 1

A basic measure of how well the planning system is working – calculated as the “number of promises/activities completed on the day stated” divided by the “total number of promises/activities made/planned for the week”. It measures the percentage of assignments that are 100% complete as planned.

Plan of the Week (POW)

A construction acronym used to identify a weekly planning meeting during which a Weekly Work Plan is developed.

Plan Production Line

A Production Line© representing a plan to complete a Schedule Task; a Schedule Task may have one or more Plan Production Lines.

PPC Metric

The vertical measurement of the difference between a Plan or Projection Line and the Actual Production Line.

Predecessor Sequential Task

A Sequential Task that must precede a Successor Sequential Task.


Most meaningfully represented as Work Quantity expressed in its Native Unit of Measure over time such as cubic yards per day. While Production can be expressed utilizing the Normalized Unit of Measure, it is less meaningful however it does have use in illustrating certain concepts of Production Control.

Production Balancing

When the Production of Sequential Tasks are equal, they are said to be balanced; they all proceed at the same rate. Production Lines© are balanced when they are parallel on a Production Graph©.

Production Control

Used to focus on how work is planned, executed and improved. The synonym for control is direction; Control deals with future expectations.

Production Graph

A 2D graphical representation of work progress; the vertical axis representing work accomplished and the horizontal axis representing time.

Production Line

A line plotted on a Production Graph made up of a series of related work and time coordinates. The slope of these lines at any particular point is Production. Production Line can have a number of contexts to include Plan, Actual, Average, Projection and Summary.


A set of interrelated Tasks to be executed over a fixed period and within certain cost and other limitations to achieve a specific goal.

Project Controls 2

Used to satisfy project accounting and reporting requirements. The synonyms for controls are ‘measurements’ and ‘information’; Controls deal with facts, that is with events of the past.

Projection Production Line

A Production Line© where a Task Assignee can project how an “in progress” Schedule Task will be completed. By definition the current Projection Production Line starts where the current Actual Production Line ends for a specific period. A Schedule Task may have one or more Projection Production Lines for a given period.

Pull 1

A method of advancing work when the next in line customer is ready to use it. A “Request” from the customer signals that the work is needed and is “pulled” from the performer. Pull releases work when the system is ready to use it.

Pull Planning 1

Used to design a project-based production system in conformance with Lean principles; s a collaborative approach that includes those who are directly responsible for supervising the work on the project.

Push 1

An “Order” from a central authority based on a schedule; advancing work based on central schedule. Releasing materials, information, or directives possibly according to a plan but irrespective of whether or not the downstream process is ready to process them.



A representation of work for a particular task; used to measure progress and completion of a Task.

Quantity Remaining

Work Quantity at Completion minus Quantity to Date as of a specific date.

Quantity at Completion (QAC)

Estimated Work Quantity required to complete a Task.

Quantity to Date (QTD)

Work Quantity completed for a Task as of a specific date (date sensitive).


Relative Time

Used to represent a nonspecific duration of time on a Production Graph© (e.g. Week 1, week 2, Week 3…) as opposed to Specific Time.


Schedule Production Line

A Task Type intended to be used in the scheduling process.

Sequential Tasks

A series of Tasks that must ne accomplishes in a specific sequence (e.g. excavate the foundation, pour the foundation, backfill the foundation)

Specific Time

Used to represent a date specific duration of time on a Production Graph© as opposed to Relative Time (e.g. 1 May, 8 May, 15 May…)

Split Task

A Task that has been divided into sub-Tasks in order to provide additional Production or Project Control metrics creating a Dimensional capability. Splitting a Tasks creates a "Parent/Child" relationship. Tasks can be split multi-generationally creating grandparent/parent/child... relationships. The sum of all Child Work Quantities must equal the Parent Work Quantity; Parent and Child must have the same Native Unit of Measure.


Any individual or organization that has an interest in the progress or completion of a Project. Stakeholders can range from an individual worker to a foreman, to a project manager, to an executive, to an engineer, to an architects, or to a project owner.

Successor Sequential Task

A Sequential Task that must follow a Predecessor Sequential Task.

Summary Production Line

A weighted Production Line© that summarizes a selected number of detail Production Lines©whose behavior automatically mimics the detail behavior based on the weighting scheme.

Superscript Production Line

The Superscript Production Line is the Production Line® to which the Base Production Line is being compared to when developing an Efficiency Metric. Noted as Base Production Line Superscript Production Line.


Takt Time

A work structuring method used to balance cycle times between Sequential Tasks. Generally accomplished in 6 steps:

  1. Establish Production data
  2. Location Identification & Cycle Time (Tact Time) Definition
  3. Task Sequence
  4. Production Balancing by Resource Leveling
  5. Create Production Graph to show Task relationships
  6. Measure Production and adjust as necessary

Target Production

The Production used to create an Ideal Production Line; the Production targeted for ideally completing a Task assuming no external impacts such as learning curve, holidays or weather.


An identifiable item of work with a measurable start and end necessary to complete a Project.

Task Assignee

The person or group that makes assignments and directs work to complete a Task. (Last Planner® in LCI terms)

Task Completion

Task Start

Task Start

Task Type

A Task categorization identifying the underlying Project Controls or Production Control purpose; a Task may have one or more Task Types(e.g. Cost Controls, Billing Controls, Payment Controls, Schedule Control, inventory controls…).

Task Work Structure

A Work Structure designed utilizing Pull concepts employing Sequential Tasks, Task and Split Task models and capabilities to facilitate the creation of a Management Centric Work Schedule. Developed in the Backward Work Structure Pass.



Occurs when a Task's actual Production is lower than its planned Production


Value 1

What the Customer wants from the process. The customer defines Value.

Value Stream 1

The sequence of activities required to design, produce and deliver a good or service to a customer, and it includes the dual flows of information and material.

Value Stream Mapping 1

A team-based methodology for analyzing the current state and designing a future state for a series of events that take a product or service from its beginning through to the Customer.

Visual Management 1

Placing tools, parts, production activities, plans, schedules, measures and performance indicators in plain view, This assures that the status of the system can be understood at a glance by everyone involved and actions taken locally in support of system objectives


Waste 1

The opposite of Value. There are seven basic types of waste including: defects, waiting, transportation of goods, motion, inventory, overproduction, and unnecessary process steps.

Weekly Work Plan(WWP) 1

The commitment-level (“will”) planning step of LPS identifying the promised task completions agreed upon by the Task Assignees. The WWP is used to determine the success of the planning effort and to determine what factors limit performance. It is a more detailed level than the Look-ahead and is the basis of measuring PPC.

Weekly Work Planning 1

The process by which the Last Planner®establishes the plan for the coming period.

Work Flow 1

The movement of information and materials through networks of interdependent specialists.

Work Quantity

The amount of work used to measure completion progress of a Task such as lineal feet, cubic yards or tons.

Work Quantity Note

Relevant Note for a reported Work Quantity

Work Structure 1

Designing the production system to determine who does what, when, where and how, usually by breaking work into pieces, where pieces will likely be different from one production unit to the next. The purpose of work structuring is to promote flow and optimize system throughput by focusing on handoffs and opportunities for moving smaller batches of work though the production system.


1=Courtesy Lean Construction Institute

2=R. Arbulu, H. Choo, M Williams (2016). Contrasting Project Production Control