When $20 Billion behemoth Builders First Source (BFS) launched a robotic truss line in April, CMs were surprised that they would select House of Design (HoD)’s first truss machine, and the industry’s first robotic floor truss line. Remarkably, after just over 3 months, they’ve achieved a steady stream of production in one of their Atlanta plants. Greg Griggs, BFS’s SVP of Manufacturing, acknowledges the developmental nature of this venture, but also the inevitability of robotics, and prefers to be a leader and shape the technology, rather than be a follower. On first glance, floor trusses seem to be the best entry point for robotics because of their uniformity. However, BFS will also be tackling roof truss robotics in one of their Texas plants later this month. But for both roofs and floors, the devil is in the details. And with BFS already committed to 8 more HoD systems, they’re especially committed to overcoming any obstacles in their way.
Lumber variances, always the bane of automation, are being put-to-the-test by the Southern Pine (SYP) material running through the BFS-HoD installation. Prior machinery offerings often struggled with the increased variability of SYP over the European or Canadian Spruce upon which they were developed. With SYP, the wane on a board may extend halfway through its thickness, which is particularly troublesome for robotic grippers.
Short pieces also challenge robotic assembly and plating, even if pieces are cut accurately and are without defect. Ribbon blocks are part of nearly every floor truss and are connected with miniscule truss plates. Bearing blocks, beam pockets, and other special details occur less often, but further complicate assembly. As Greg Griggs reiterated from the outset, the HoD system must handle these end and interior details, and today he reports that HoD is making progress.
Unique about the BFS/HoD robotic floor line is that it produces two trusses on each cycle, and that it has been designed to work with two assemblers. Their primary function is to seat truss plates after the robots precisely position all parts on the table. Their secondary job is to hustle into the protected workspace and resolve glitches. Perhaps this intervention won’t be necessary with a more mature system, like the one we will examine next month. But, over time, BFS and HoD can attack these glitches and, with enough effort, resolve most of them. All the while, the line can be running and proving its viability.
And finally, what is most promising about robotic assembly of floor trusses is the potential for them to displace EWP floor systems. As output likely will ramp up, much of the cost advantage held by totally automated EWP mills will be diminished. Then the primacy of the open web design can be the decisive factor. This has come about because cutting holes in I-Joists has dramatically increased the cost and the overhead of putting together EWP packages. And the number of I-Joist penetrations has been dramatically increased, as energy codes have forced HVAC runs into floor cavities. The final straw may be the adoption of modern Rheia ducting (see my April 2022 The Last Word on Rheia HVAC Systems) which greatly advantages open web design.
As the largest seller of EWP, BFS is the ideal entity to drive forward the automation of floor trusses and arguably has the most to gain. This is wholly consistent with their corporate mandate to continually increase their sales of manufactured products over commodities. When Greg Griggs and his team proves that they can make more money for BFS with floor trusses than I-Joists, and builders gain tangible installation cost advantages, floor trusses will regain their proper share of residential construction.