1) Defects
Anything that wasn’t done correctly the first time and must be repaired, replaced or redone. This includes damaged material, rework, or punch list items. A flooring material not installed per the specifications or a finished wall damaged by the electrical contractor would fall under that category.
2) Overproduction
Fabricating material too soon or ordering extra material because of poor quality, as opposed to “Just-in-time” thinking, which consists of producing and delivering the right amount of material at the time it is needed for production. While it’s easy to label excess material as waste, material being delivered too soon is also wasteful since it results in excess inventory, which may then need to be discarded should the design change.
3) Inventory
Being burdened by excess materials, often caused by overproduction. This includes material stored on-site or at the fabrication yard, work in progress, and unused tools & parts. While having some inventory on hand is necessary to keep the project going, these materials should be minimized as much as possible, as they tend to require a fair bit of handling and storage space.
4) Extra Processing
Unnecessary steps in the project value chain, such as transforming or double-handling material. There are also a lot of coordination and administrative workflows on a construction project that can lead to double data entry: multiple signatures on forms, organizing field notes into a report, redundant daily logs, and forwarding emails with drawings and RFIs to the field, to name a few.
5) Motion
Extra steps are taken by people to accomplish their work as a result of inefficient processes. This includes time spent looking for a tool or file, as well as walking extra yards due to poor layout of the work area.
6) Transportation
Unnecessary movement of materials or equipment. This can involve movement from one jobsite to another, or from a yard to a material laydown area and then again to the actual work area. While this type of waste cannot be eliminated 100%, transportation should be minimized as it not only adds time to the whole construction process, but also exposes the material to handling damage.
7) Waiting
Crews waiting for the delivery of material or equipment, or the completion of a preceding activity. This also applies to anyone on the project waiting for information, such as field personnel waiting for a plan or an RFI, a scheduler waiting for progress updates, or payroll waiting for time sheets.
8) Underutilized Talent
Failing to make use of people’s skills, creativity, or knowledge on the project. This is not one of the Seven Wastes (or 7 Mudas) found in Lean literature, but it is accepted as an additional waste commonly found in the industry. Your people are your greatest asset, and they should be empowered and listened to in situations that could benefit from their strengths.
