The installation of solar mounting structures is a repetitive and time-sensitive process, making it a perfect setting for applying the principles of lean construction. Of course, some basic steps to installation can’t be changed, like drilling pilot holes or wearing safety harnesses. But crews can think and plan ahead on a larger scale. They can anticipate what will happen next and finish more quickly. For example, shaving off a single minute from a step repeated 60 times saves one hour of labor. To apply lean construction philosophy to projects, managers should think of projects as a production system.
Quickly and efficiently executing a job contributes positively to a contractor’s bottom-line. Installation crews range in size from three members on a residential installation to 100 or more members on large-scale projects. Optimized operations maintain work flow, while minimizing costs and time, reducing materials and tools (especially on a roof) and eliminating wasted movements. Shaving a minute off a step that 60 installers do 60 times saves more than a week of labor. Lean solar construction works to drive waste out of processes, streamline work flow—including having the right tools accessible—and dedicate appropriately skilled teams with tasks that work in parallel whenever possible.
A pre-determined plan is key to success. Here’s an example, based around a hypothetical residential installation:
Two people get on a roof with safety harnesses and construction aprons. One stays on the ground. Once anchored, one roof person marks the roof while the other locates rafters and inserts flashings. As marking finishes, that person helps complete flashings installations, a time-consuming phase of the project. Anticipating the roof team’s needs, the ground person loads a bucket with flashings, lag bolts and L-feet, and gets the first row rail ready for installation. This plan of action continues until the array is finished.
Streamlined processes keep the roof clear of debris and improve safety, so lanyards don’t get hung up on excess boxes and parts, less material is moved around and everyone has assigned tasks that get done in parallel. As a result, no one is waiting for the next step.
For more information, check with your racking company product specialists.
This tip was contributed by Andy Davidson, project and engineering solutions manager at Unirac.