Capitalizing on CrossLam
October 24, 2017•News
By Erica Spiritos- Mass Timber Specialist at Structurlam
If you attended the Mass Timber Conference in Portland this past spring, you may have heard me compare the construction of a building to the construction of a rocket. Here is a story I think we can learn from:
When Elon Musk decided to embark on a mission to explore Mars and propel the human species toward an interplanetary existence, he started with several visits to Russia to inquire into the cost of an intercontinental ballistic missile (ICBM) – the closest thing to a launch vehicle available for purchase and potentially affordable. Russia, it turns out, was selling repurposed ICBMs for $7M apiece, or $21M for three. The negotiations escalated over several months, but by the third meeting, Russian officials changed the game and insisted that the price was $21M for ONE. (I imagine the GCs reading this can relate!)
Elon, undeterred, was forced to consider more creative alternatives: on the flight home from Russia, Musk and his partner resolved to build a rocket themselves.
At this point, Elon asked himself this crucial question: What is the ratio of costs between atoms and the arrangement of atoms? Or, put another way, what are the costs of the raw materials required to construct a rocket? And how can we optimize our assembly to reduce the costs of putting the pieces together, and minimize the overall project expense?
What does this have to do with buildings? And what is the connection to CrossLam?
Elon calculated the cost of raw materials to be roughly 2% of the overall cost of an ICBM, meaning that roughly 98% of the cost was related to the way in which materials were assembled. In theory, if we could wave a magic wand so that the cost of rearranging the atoms were zero, what would be the total cost of the ICBM? What would be the total cost of a building?
Prefabricated CLT and Glulam structures are, I believe, the key to decreasing the overall cost of arranging the atoms.
On its own, a CLT panel is a material with intrinsic advantages. It comes from renewable materials. It has a high strength to weight ratio. It is dimensionally stable. It spans in two directions. Within this category of material, however, exists a spectrum of opportunity and cost.
A “raw billet” (what we call a non-customized rectangle of CLT) exists at the bottom end of this spectrum. A custom CrossLam panel exists at the other end. This custom panel is fabricated not as a commodity product but as a unique building component destined for a specific location in a specific project. It is CNC-machined to millimeter precision. It includes penetrations for sprinklers, lighting, HVAC ducts, skylights, etc. It is loaded on a truck in reverse order of installation so that it can be picked directly from the truck bed and craned into place. The same spectrum exists for glulam. On one end, we have sticks cut to length. On the opposite end, we have CNC-framed columns and beams, in which steel connections have been either test-fit or pre-installed in a quality-controlled factory, where the weather is a non-issue.
This unique building component has a higher cost, for the level of services and coordination that have been integrated into the product. I wonder: what is the VALUE of these services? What are the advantages from a schedule point of view? What are the benefits of this level of predictability, of knowing that all pieces will arrive on-site in order of their installation and will fit together seamlessly? We hear all the time that it costs three times more to do something in the field as it does to do in the shop. How can we carry this logic into our cost models, into our evaluation of structural design, construction, and procurement options? How can we find ways to spend the money where it counts? How can we honor the building as a system of integrated parts?