To expedite the adoption of pre-built wall panels, shop labor must be significantly lower than site labor. That means replacing hand-nailing, measuring, cutting, and manhandling with practices that have been proven in truss fabrication. In addition, major builders and reluctant framers demand the same degree of precision with panels that they have grown to expect from trusses. To achieve this exactitude in a dwindling labor market dictates adoption of the best manufacturing practices:
Optimal Material Sourcing means storing and handling raw materials efficiently, just in time for cutting. Given that linear saws like the Blade can cut all parts, header material can be stored with stick lumber close to the saw infeed and fed to the saw just in time. Soon automated retrieval systems like the Ranger will drastically reduce the labor to feed the saw for wall panel parts.
Precision Cutting is imperative on all wall parts, but identification of resulting indistinguishable pieces is just as critical. These parts need to be marked as they are cut to lessen downstream handling and to guide framing, and is best done with a linear saw. There is no better way to cut the studs of rake panels.
Likewise, the X-Y saw has been reborn to rip and crosscut sheathing, eliminating manual measurements.
Just-in-Time supply of panel parts means that ALL necessary pieces and assemblies are delivered to framers marked and ready to put together. CMs have begun investigating “cart bots” – robotic carts with optical sensors that can be summoned from tables to deliver the next cart of assembly parts to the table. Walmart has patented such a system for retrieving and returning shopping carts to/from holding areas.
Kanban aggregation of repetitive parts, like studs, jack-sets, and sheathing, combines the best of both mass production and just-in-time practices. The component nailer is also being re-adapted in this vein to lessen labor and minimize hand-nailing in the production of carts full of these common components.
Workflow Control via programs like ShopNet eliminates paperwork, expedite the workflow, and now enable labor tracking. The inclusion of extensive blocking and sheathing holdbacks/extensions has debunked the linear-foot-costing model. Measuring actual labor consumption and comparing it to estimated labor enables much more accurate pricing going forward, and is the key to panel profitability.
Proper Integration of Automation is essential, so that an automated piece of equipment, like a sheathing bridge, is not dependent on imprecise hand-nailing of studs. Since the bridge operator keys off the nail heads, if they are off by even a one quarter inch, the sheathing fasteners are likely to miss the studs, causing rework or, at worst, rejection in the field. Safety and integration of automation will require use of nail carriages on framing tables, long since rejected by framers, but far superior in accuracy.
More Innovation is being sought to leverage the efficiency of the Single Tool Bridge by production managers like Owen Eldridge of Homestead Building Systems. Owen believes an automated sheathing bridge is needed so that he may redeploy the operator to stack panels or other tasks while sheathing is automatically nailed. Any innovation that reduces staffing on the panel line is worth trying, according to Owen, and clearly innovation in the wall panel business is just beginning.