Production Control Best Practices #12: Coordinate logistics and lay-down areas with your production plans
It is a common problem that deliveries and lay-down areas interfere with production plans. Stacked materials prevent subcontractors from completely finishing locations. Deliveries are planned on an ad-hoc basis and/or the materials are in wrong locations. Materials are delivered far too early and in too large quantities. This makes it convenient for subcontractors to work out-of-sequence where materials are easily available. The plans should be synchronized to prevent loss of productivity and out-of-sequence work.
5D models include detailed quantities of materials related to each location. In a project managed with location-based principles, deliveries and storage should also follow the same Location Breakdown Structure. The original plan can be used to schedule rough delivery times and quantities. Forecasts provide more real-time information and can be used to “pull” deliveries in. We recommend that deliveries are scheduled as close to actual production as possible based on Lean Construction principles. Any deliveries which are scheduled well-ahead of production should always require approval by the General Contractor. Often subcontractors want early deliveries to maximize their cash flow. However, these deliveries are not adding value to the project before the materials are actually incorporated to the building…
Caption: Here is a perfect example of logistics gone wrong on a jobsite. The holding area for scrap steel is rising faster than the building structure.
Even with pull scheduling deliveries, some long-term storage may be necessary. Depending on space availability, it may make sense to create specific locations for lay-down areas and bypass these locations on the first pass through the building. All trades finish all their work in other locations and then move on to these “storage” locations. Big open spaces with little interior work are often good candidates for this. A best practice is to show these areas in a 4D simulation by modeling a pile of materials for each trade and removing these elements when the work is finished on that floor.
Handling logistics and deliveries properly can make the plan happen. If materials are only available in the location where work is supposed to be taking place, it is very inconvenient to work out-of-sequence. I have seen a few projects where deliveries were allowed only just before production and there were very few tasks which did not follow the planned sequence. This increases productivity and production rates for everyone and enables significant duration compression.
To learn more about representing deliveries and lay-down areas in your planning, please refer to the following resources.
Video Training: Schedule Planner Video Training – Level 6
FAQs: 4D Manager
Be sure to catch up on past articles in this LBMS and Production Control best practice series: