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→ see Tasks Anticipated

Tabular Method [CBA]

A method for Choosing By Advantages, especially for complex decisions.

Step 1: Gather all relevant stakeholders and determine impasse resolution method.
Step 2: Choose alternatives likely to yield important advantages.
Step 3: Define factors to evaluate the alternatives.
Step 4: Define must criteria and want criteria for each factor.
Step 5: Identify attributes of each alternative that speak to the criteria.
Step 6: Underline the least preferred attribute in each factor by criterion (row by row).
Step 7: Calculate advantages for each factor by comparing each attribute to the least preferred attribute.
Step 8: Circle the most important advantage for each factor/criterion.
Step 9: Choose the paramount advantage among all the most important advantages (circled in step 8).
Step 10: Assign the maximum importance score to the paramount advantage.
Step 11: Assign importance scores to the most important advantages based on the paramount advantage.
Step 12: Assign importance scores to the other advantages based on the most important advantages and the paramount advantage.
Step 13: Sum importance scores for each alternative.
Step 14: Evaluate cost data if applicable.

takt, takt time

[unit of time]

Takt is the German word for “beat,” referring to the regularity with which something gets done.

It is the maximum unit of time within which a product must be produced (supply rate) in order to match the rate at which that product is needed (demand rate).


If you have a total of 8 hours (480 minutes) in a shift (gross time) and subtract 30 minutes lunch, two 15 minutes breaks, 10 minutes for a team briefing, and 10 minutes for basic maintenance checks, then the net time available to work = 480 min – 30 min – 2 * 15 min – 10 min – 10 min = 400 min.

If customer demand was, say, 400 units per day and you were running one shift, then the takt time must be set at 1 minute. Your line would be required to produce one unit every minute in order to be able to keep up with customer demand.

Takt Time Planning (TTP)

Use of takt time in the course of work structuring in order to develop a (phase) plan with smooth work flow.

Target Cost (TC) [TVD]

[unit of money]

In Target Value Design, the cost that a project team is striving to achieve, either less than or equal to the allowable cost, and typically a stretch goal relative to previous performance capability.

Note that the project target may be set in terms of scope: to deliver more value for a given cost.

Target Value Design (TVD)

The practice of defining scope, performance goals, and target cost in advance of starting design, and then steering the design and construction process so as to meet all.

Macomber and Barberio (2007) coined the term “target value design” proposing practices different from conventional project management namely:

“Rather than estimate based on a detailed design, design based on a detailed estimate.
Rather than evaluate the constructability of a design, design for what is constructable.
Rather than design alone and then come together for group reviews and decisions, work together to define the issues and produce decisions then design to those decisions.
Rather than narrow choices to proceed with design, carry solution sets far into the design process. [in other words, practice set based design]
Rather than work alone in separate rooms, work in pairs or a larger group face-to-face.”

Macomber, H. and Barberio, J. (2007). “Target-Value Design: Nine Foundational Practices for Delivering Surprising Client Value.” Lean Project Consulting, Inc.,, self-published, 3 pages.
Tommelein, I.D. and Ballard, G. (2016). Target Value Design: Introduction, Framework, and Current Benchmark. P2SL Report, Project Production Systems Laboratory, University of California, Berkeley, CA, March, 51 pp.

task [LPS]

Description of a part of an activity as it gets exploded into smaller pieces (boulder – rock – pebble – grain/dust) in the make-ready planning process to address the concern of making means meet ends (e.g., by operation design in first run studies).

Specific type and amount of work assigned to a production unit that the production unit can commit to performing.

Tasks Anticipated (TA) [LPS]

A lookahead metric in the Last Planner System that gauges the percentage of all tasks in a plan for a target week, that were anticipated in an earlier plan for that target week.

TA is the ratio of the number of tasks common to two sets of tasks, one set further out from- and the other closer to the tasks’ execution time, to the total number of tasks in the set closer to execution. These sets could be any number of time periods apart, in general TAj-to-i

Together with Tasks Made Ready (TMR) it characterizes the ability of the planning team to make work ready.

Example: Assume today is June 2.

The plan for June 5-9 in the 4-week LOOKAHEAD May29-Jun23, was labeled WEEK 2 as it was two weeks prior to execution. It consisted of the set of tasks A, B, C, D, E, and F. The plan for that same week, June 5-9, but updated one week later as shown in the 4-week LOOKAHEAD Jun05-Jun16, is now labeled WEEK 1 as it is one week prior to execution. It consists of the set of tasks B, D, E, G, and H. Thus, 3 tasks appear in both sets, namely B, D, and E.

Accordingly, TA2-to-1 = BDE/BDEGH = 3/5 = 60%.
In other words, 60% of the tasks in a later plan for the target week were anticipated in an earlier plan for the week.

Accordingly, TMR2-to-1 = BDE/ABCDEF = 3/6 = 50%
In other words, 50% of the tasks in an earlier plan for the target week were made ready in the later plan for that week.

Note: PPC = TMR1-to-0


Image by Iris D. Tommelein, all rights reserved, (c) 2016.

Tasks Made Ready (TMR) [LPS]

A lookahead metric in the Last Planner System that gauges the percentage of all tasks in a plan for a target week, that are included in a later plan for that target week. It describes the ability of the plan(ner) to forecast (predict) accurately at one point in time what tasks will take place at another point in time in the future.

TMR is the ratio of the number of tasks common to two sets of tasks, one set further out from- and the other closer to the tasks’ execution time, to the total number of tasks in the set further out. These sets could be any number of time periods apart, in general TMRj-to-i

Together with Tasks Anticipated (TA) it characterizes the ability of the planning team to make work ready.

Example and illustration → see Tasks Anticipated (TA)


→ see Target Cost

Transformation Flow Value, TFV theory of production

Theory of production that recognizes three competing schools of thought exist in production management:

  1. the transformation view (predominant in Project Management),
  2. the flow view, and
  3. the value view.

In lean construction, all three are pursued at the same time.

Reference: Koskela, L. (1992). Application of the New Production Philosophy to Construction. Technical Report 92, CIFE, Stanford University, Stanford, CA.


Image source: Iris D. Tommelein


[unit of product/unit of time]

The output rate of a production process. The number of units that are produced in a stated period of time.


→ see Tasks Made Ready


Range of variation permitted in a specified dimension or location (1D, 2D, or 3D) without impacting structural integrity, operating capability, or abutting components (after CII 1993). This definition pertaining to geometry equally applies to any material, resource, or process property such as duration, temperature, impact strength, etc.

Reference: CII (1993). Constructability Implementation Guide. CII Special Pub. 34-1, Univ. of Texas, Austin, TX.

total time

[unit of time]

Time (lead time, cycle time, or both) computed as the sum of value-added time (VAT) plus non-value added time (NVAT) in a process.

Toyota’s 14 Principles

→ see Principles of the Toyota Way


Toyota Production System; Thinking People System.

Reference: Ohno, T. (1988). The Toyota Production System: Beyond Large-Scale Production. Productivity Press, Portland, OR. 143 p.

transfer batch

→ see batch


The conversion (changing of characteristics) of an input into an output.


One of 7 wastes defined by Ohno (1988) referring to unnecessary movement of products and materials. This may be reduced by one-touch handling: lifting materials off the truck and positioning them in their final location without rehandling (no laydown or staging).

true north

The ideal or a set of principles that a business sets out to strive for.


→ see Target Value Design

Two-list Method [CBA]

A method in the decisionmaking system called Choosing By Advantages, used to choose one of two alternatives.