Intro to Lean Midterm Vocab

Rework

Work that has to be done twice, including punch lists and tear-outs. It accounts for roughly 10% of project costs.

Interoperability

The ability of different software systems across the design and construction supply chain to exchange information smoothly; poor interoperability causes annual losses between $17 billion and $36 billion due to communication difficulties.

Rethinking Construction

A 1998 landmark report from the UK that issued 15 key recommendations to overhaul the construction sector, including senior leadership commitment, client focus, better health and safety, integrated processes, and lean thinking.

Craft Production

Highly skilled workers building one product for one customer at a time (e.g., custom furniture, art, hand-built cars); it was too expensive for most consumers.

Mass Production

Unskilled and semi-skilled workers using specialized machines to produce standardized products in huge quantities; it is cheap and uniform, but rigid and wasteful.

TPS (Toyota Production System)

The production system developed by Toyota (led by Eiji Toyoda and Taiichi Ohno) that forms the foundation for every lean tool used today.

Just-in-Time (JIT)

A pillar of the TPS house meaning to make only what is pulled, paced by takt time and signaled by kanban.

Jidoka

A pillar of the TPS house meaning to stop the line for quality issues, building quality into the process rather than inspecting it at the end.

Kanban

Japanese for "card"; a visual pull signal used to control production where nothing moves without a card saying "send me one more".

Takt

German for "beat" or pulse; calculated as available production time divided by customer demand to establish the exact production pace.

Genchi Genbutsu

"Go and see for yourself"—the practice of managers going directly to the jobsite floor without clipboards or reports to observe the work and find waste firsthand.

Kaizen

Japanese term for "change for the better" or continuous improvement.

Buffer

An allowance of extra inventory, extra time, or extra people held in reserve so that surprises never stop the production line.

DOWNTIME

The modern 8 Wastes of Lean: Defects, Overproduction, Waiting, Non-utilized talent, Transportation, Inventory, Motion, and Excess processing.

TIMWOOD

Shigeo Shingo's original 7 Wastes: Transportation, Inventory, Motion, Waiting, Overproduction, Processing (Excess Processing), and Defects.

Data Date

A snapshot in time used to compare planned progress versus actual progress in earned value analysis.

BCWS (Budgeted Cost of Work Scheduled / PV)

The approved cost baseline planned to be spent on a given activity over a specified period of time.

BCWP (Budgeted Cost of Work Performed / EV)

The earned value of work actually completed to date.

ACWP (Actual Cost of Work Performed / AC)

The total actual costs incurred in performing work on an activity in a given period.

Earned Schedule

An extension of earned value that translates monetary schedule variance into time units (such as months or days).

Project Control vs. Change Control

Project control monitors how effectively a project follows its plan, while change control provides a formal process for identifying change requests and processing changes; both traditional processes are reactive, whereas Lean control is proactive.

Seiri (Sort)

Step 1 of 5S; keeping only what is necessary in the work area and discarding or red-tagging everything else.

Seiton (Set in Order)

Step 2 of 5S; arranging and labeling necessary items using shadow boards, labeled bins, and floor markings for easy use and instant retrieval.

Seiso (Shine)

Step 3 of 5S; keeping everything swept and clean so daily cleaning doubles as inspection for safety and preventive maintenance.

Seiketsu (Standardize)

Step 4 of 5S; the state where the first three S's are maintained as a repeatable routine using color-coding, checklists, and signage.

Shitsuke (Sustain)

Step 5 of 5S; making it a habit through regular audits, recognition, and leadership walkthroughs to maintain correct procedures.

Red Tag

A marker used during the Sort phase to tag items you are unsure about keeping or discarding.

Shadow Board

A visual organization board where tools have designated silhouetted outlines so missing items or gaps are immediately obvious.

Visual Controls

Standardized visual cues and displays used to maintain workplace order and eliminate waste.

Servant Leadership

A leadership style that views leadership as an opportunity to serve others, shares power and control to drive engagement, measures success through growth, listens, and understands it is not about them.

Sensei

A teacher or coach who guides teams on their Lean journey.

Constraint Log

A log used in make-ready planning to identify site constraints, record commitments to remove them, and assign owners.

PPC (Percent Plan Complete)

The percentage of planned weekly commitments successfully completed by the project team.

Variance Reasons

Documented explanations for why planned commitments were missed during weekly work planning.

Make-Ready

The look-ahead planning phase (1,000-foot level) focused on identifying and removing constraints so work can be made ready to execute.

Obeya (Big Room)

Japanese for "Big Room"; a project approach bringing key individuals together to speed communication, accelerate decisions, and reduce siloed thinking.

Latency

The lag time between asking a question and getting an actionable answer you can build on.

Champion

An empowered decision-maker in a Big Room session who has the authority to say "yes".

Facilitator

A peer (not a boss) who keeps the Big Room meeting agenda moving forward and calls ELMO when needed.

Timekeeper

A role responsible for enforcing hard time stops and saying times out loud.

Scribe

A role responsible for updating the decision log and managing the parking lot.

Decision Log

A record on the Big Room wall tracking what was decided, who owns it, and the completion date to prevent re-deciding issues.

Plus/Delta

A quick feedback tool used at the end of a session to evaluate what produced value and what should be changed next time.

Customer

The person making a request in a promise network.

Performer

The person fulfilling the requested action in a promise network.

Conditions of Satisfaction (CoS)

Measurable, negotiated statements agreed upon by the customer and performer that define what tests a project or task must pass to be accepted as a success.

Counteroffer

An alternative response a promiser can make instead of accepting or rejecting a request outright.

Trust

A core foundation built on sincerity, consistency, reliability, integrity, competence, and commitment.

Daily Huddle

A short, 10-minute standing coordination meeting used to review area, work today, handoffs, constraints, and asks to enable rapid learning.

Visual Management

Using visual displays, boards, and 5S tools to track metrics, status, and workflow transparently on the jobsite.

Gemba

The actual place where work is done and value is created ("go to see to understand reality").

Value Stream Mapping

A team method to map and analyze current flow and design a future state that removes waiting, overstock, and rework.

Value-Added Ratio

The ratio of value-added work time divided by total lead time.

Lead Time

Total elapsed time from order to delivery, during which most time is spent waiting rather than working.

PDCA

Plan-Do-Check-Act; the foundational scientific cycle used for continuous improvement.

First Run Study (FRS)

A short, planned trial execution of a process using PDCA to determine the best means, methods, tools, and sequence before full rollout.

Standard Work

A description of the best-known method for a task, including task sequence, timing, expected output, and quality checks, used to reduce variation.